v16.0.0

Prepare changelog for v16.0.0
v16.0.0-rc.1
2022-03-15 14:17:54 +00:00 · 2022-03-15 14:17:54 +00:00 · 2022-03-08 14:43:46 +00:00 · 2022-03-08 13:31:50 +00:00 · 2022-03-04 15:56:14 +00:00 · 2022-03-04 14:03:35 +00:00
143 changed files with 14101 additions and 7595 deletions
@@ -31,6 +31,9 @@ module.exports = {
        "no-async-promise-executor": "off",
        // We use a `logger` intermediary module
        "no-console": "error",
+
+        // restrict EventEmitters to force callers to use TypedEventEmitter
+        "no-restricted-imports": ["error", "events"],
    },
    overrides: [{
        files: [
@@ -0,0 +1,6 @@
+comment:
+  layout: "diff, files"
+  behavior: default
+  require_changes: false
+  require_base: no
+  require_head: no
@@ -0,0 +1,19 @@
+name: Test coverage
+on:
+  pull_request: {}
+  push:
+    branches: [develop, main, master]
+jobs:
+  test-coverage:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Run tests with coverage
+        run: "yarn install && yarn build && yarn coverage"
+
+      - name: Upload coverage
+        uses: codecov/codecov-action@v2
+        with:
+          verbose: true
@@ -1,3 +1,395 @@
+Changes in [16.0.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v16.0.0) (2022-03-15)
+==================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Improve typing around event emitter handlers ([\#2180](https://github.com/matrix-org/matrix-js-sdk/pull/2180)).
+
+## ✨ Features
+ * Fix defer not supporting resolving with a Promise<T> ([\#2216](https://github.com/matrix-org/matrix-js-sdk/pull/2216)).
+ * add LocationAssetType enum ([\#2214](https://github.com/matrix-org/matrix-js-sdk/pull/2214)).
+ * Support for mid-call devices changes ([\#2154](https://github.com/matrix-org/matrix-js-sdk/pull/2154)). Contributed by @SimonBrandner.
+ * Add new room state emit RoomStateEvent.Update for lower-frequency hits ([\#2192](https://github.com/matrix-org/matrix-js-sdk/pull/2192)).
+
+## 🐛 Bug Fixes
+ * Fix wrong event_id being sent for m.in_reply_to of threads ([\#2213](https://github.com/matrix-org/matrix-js-sdk/pull/2213)).
+ * Fix wrongly asserting that PushRule::conditions is non-null ([\#2217](https://github.com/matrix-org/matrix-js-sdk/pull/2217)).
+ * Make createThread more resilient when missing rootEvent ([\#2207](https://github.com/matrix-org/matrix-js-sdk/pull/2207)). Fixes vector-im/element-web#21130.
+ * Fix bug with the /hierarchy API sending invalid requests ([\#2201](https://github.com/matrix-org/matrix-js-sdk/pull/2201)). Fixes vector-im/element-web#21170.
+ * fix relation sender filter ([\#2196](https://github.com/matrix-org/matrix-js-sdk/pull/2196)). Fixes vector-im/element-web#20877.
+ * Fix bug with one-way audio after a transfer ([\#2193](https://github.com/matrix-org/matrix-js-sdk/pull/2193)).
+
+Changes in [16.0.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v16.0.0-rc.1) (2022-03-08)
+============================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Improve typing around event emitter handlers ([\#2180](https://github.com/matrix-org/matrix-js-sdk/pull/2180)).
+
+## ✨ Features
+ * Fix defer not supporting resolving with a Promise<T> ([\#2216](https://github.com/matrix-org/matrix-js-sdk/pull/2216)).
+ * add LocationAssetType enum ([\#2214](https://github.com/matrix-org/matrix-js-sdk/pull/2214)).
+ * Support for mid-call devices changes ([\#2154](https://github.com/matrix-org/matrix-js-sdk/pull/2154)). Contributed by @SimonBrandner.
+ * Add new room state emit RoomStateEvent.Update for lower-frequency hits ([\#2192](https://github.com/matrix-org/matrix-js-sdk/pull/2192)).
+
+## 🐛 Bug Fixes
+ * Fix wrong event_id being sent for m.in_reply_to of threads ([\#2213](https://github.com/matrix-org/matrix-js-sdk/pull/2213)).
+ * Fix wrongly asserting that PushRule::conditions is non-null ([\#2217](https://github.com/matrix-org/matrix-js-sdk/pull/2217)).
+ * Make createThread more resilient when missing rootEvent ([\#2207](https://github.com/matrix-org/matrix-js-sdk/pull/2207)). Fixes vector-im/element-web#21130.
+ * Fix bug with the /hierarchy API sending invalid requests ([\#2201](https://github.com/matrix-org/matrix-js-sdk/pull/2201)). Fixes vector-im/element-web#21170.
+ * fix relation sender filter ([\#2196](https://github.com/matrix-org/matrix-js-sdk/pull/2196)). Fixes vector-im/element-web#20877.
+ * Fix bug with one-way audio after a transfer ([\#2193](https://github.com/matrix-org/matrix-js-sdk/pull/2193)).
+
+Changes in [15.6.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.6.0) (2022-02-28)
+==================================================================================================
+
+## ✨ Features
+ * Return send event response from MSC3089Branch.createNewVersion() ([\#2186](https://github.com/matrix-org/matrix-js-sdk/pull/2186)).
+ * Add functions to support refresh tokens ([\#2178](https://github.com/matrix-org/matrix-js-sdk/pull/2178)).
+
+## 🐛 Bug Fixes
+ * [Release] Fix bug with the /hierarchy API sending invalid requests ([\#2202](https://github.com/matrix-org/matrix-js-sdk/pull/2202)).
+ * Fix bug where calls could break if rejected from somewhere else ([\#2189](https://github.com/matrix-org/matrix-js-sdk/pull/2189)).
+ * Fix camera stuck on after call transfer ([\#2188](https://github.com/matrix-org/matrix-js-sdk/pull/2188)).
+ * Fix synthetic read receipt handling ([\#2174](https://github.com/matrix-org/matrix-js-sdk/pull/2174)). Fixes vector-im/element-web#21016.
+ * Revert "Sign backup with cross-signing key when we reset it." ([\#2175](https://github.com/matrix-org/matrix-js-sdk/pull/2175)).
+ * Sign backup with cross-signing key when we reset it. ([\#2170](https://github.com/matrix-org/matrix-js-sdk/pull/2170)).
+ * Fix error in uploadContent() when file is empty under Node.js ([\#2155](https://github.com/matrix-org/matrix-js-sdk/pull/2155)).
+ * Check the backup info against the stored private key when determining trust. ([\#2167](https://github.com/matrix-org/matrix-js-sdk/pull/2167)).
+ * Back up keys before logging out ([\#2158](https://github.com/matrix-org/matrix-js-sdk/pull/2158)). Fixes vector-im/element-web#13151.
+
+Changes in [15.6.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.6.0-rc.1) (2022-02-22)
+============================================================================================================
+
+## ✨ Features
+ * Return send event response from MSC3089Branch.createNewVersion() ([\#2186](https://github.com/matrix-org/matrix-js-sdk/pull/2186)).
+ * Add functions to support refresh tokens ([\#2178](https://github.com/matrix-org/matrix-js-sdk/pull/2178)).
+
+## 🐛 Bug Fixes
+ * Fix bug where calls could break if rejected from somewhere else ([\#2189](https://github.com/matrix-org/matrix-js-sdk/pull/2189)).
+ * Fix camera stuck on after call transfer ([\#2188](https://github.com/matrix-org/matrix-js-sdk/pull/2188)).
+ * Fix synthetic read receipt handling ([\#2174](https://github.com/matrix-org/matrix-js-sdk/pull/2174)). Fixes vector-im/element-web#21016.
+ * Revert "Sign backup with cross-signing key when we reset it." ([\#2175](https://github.com/matrix-org/matrix-js-sdk/pull/2175)).
+ * Sign backup with cross-signing key when we reset it. ([\#2170](https://github.com/matrix-org/matrix-js-sdk/pull/2170)).
+ * Fix error in uploadContent() when file is empty under Node.js ([\#2155](https://github.com/matrix-org/matrix-js-sdk/pull/2155)).
+ * Check the backup info against the stored private key when determining trust. ([\#2167](https://github.com/matrix-org/matrix-js-sdk/pull/2167)).
+ * Back up keys before logging out ([\#2158](https://github.com/matrix-org/matrix-js-sdk/pull/2158)). Fixes vector-im/element-web#13151.
+
+Changes in [15.5.2](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.5.2) (2022-02-17)
+==================================================================================================
+
+## 🐛 Bug Fixes
+ * Fix synthetic read receipt handling
+
+Changes in [15.5.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.5.1) (2022-02-14)
+==================================================================================================
+
+## 🐛 Bug Fixes
+ * Fix issue with rooms not getting marked as unread ([\#2163](https://github.com/matrix-org/matrix-js-sdk/pull/2163)). Fixes vector-im/element-web#20971.
+ * Don't store streams that are only used once ([\#2157](https://github.com/matrix-org/matrix-js-sdk/pull/2157)). Fixes vector-im/element-web#20932. Contributed by @SimonBrandner.
+ * Fix edge cases around RR calculations ([\#2160](https://github.com/matrix-org/matrix-js-sdk/pull/2160)). Fixes vector-im/element-web#20922.
+ * Account for encryption in `maySendMessage()` ([\#2159](https://github.com/matrix-org/matrix-js-sdk/pull/2159)). Contributed by @SimonBrandner.
+ * Send references to thread root to threads, even out of order ([\#2156](https://github.com/matrix-org/matrix-js-sdk/pull/2156)).
+ * Fix initial sync fail when event fetching unsuccessful ([\#2150](https://github.com/matrix-org/matrix-js-sdk/pull/2150)). Fixes vector-im/element-web#20862.
+ * Don't decrypt redacted messages ([\#2143](https://github.com/matrix-org/matrix-js-sdk/pull/2143)). Contributed by @SimonBrandner.
+
+Changes in [15.5.1-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.5.1-rc.1) (2022-02-08)
+============================================================================================================
+
+## 🐛 Bug Fixes
+ * Fix issue with rooms not getting marked as unread ([\#2163](https://github.com/matrix-org/matrix-js-sdk/pull/2163)). Fixes vector-im/element-web#20971.
+ * Don't store streams that are only used once ([\#2157](https://github.com/matrix-org/matrix-js-sdk/pull/2157)). Fixes vector-im/element-web#20932. Contributed by @SimonBrandner.
+ * Fix edge cases around RR calculations ([\#2160](https://github.com/matrix-org/matrix-js-sdk/pull/2160)). Fixes vector-im/element-web#20922.
+ * Account for encryption in `maySendMessage()` ([\#2159](https://github.com/matrix-org/matrix-js-sdk/pull/2159)). Contributed by @SimonBrandner.
+ * Send references to thread root to threads, even out of order ([\#2156](https://github.com/matrix-org/matrix-js-sdk/pull/2156)).
+ * Fix initial sync fail when event fetching unsuccessful ([\#2150](https://github.com/matrix-org/matrix-js-sdk/pull/2150)). Fixes vector-im/element-web#20862.
+ * Don't decrypt redacted messages ([\#2143](https://github.com/matrix-org/matrix-js-sdk/pull/2143)). Contributed by @SimonBrandner.
+
+Changes in [15.5.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.5.0) (2022-01-31)
+==================================================================================================
+
+## ✨ Features
+ * Support m.asset in m.location event content ([\#2109](https://github.com/matrix-org/matrix-js-sdk/pull/2109)).
+ * Send extensible events structure and support on-demand parsing ([\#2091](https://github.com/matrix-org/matrix-js-sdk/pull/2091)).
+ * Support cancelling events whilst they are in status = ENCRYPTING ([\#2095](https://github.com/matrix-org/matrix-js-sdk/pull/2095)).
+
+## 🐛 Bug Fixes
+ * Fix http-api butchering idServer requests ([\#2134](https://github.com/matrix-org/matrix-js-sdk/pull/2134)). Fixes vector-im/element-web#20680.
+ * Don't remove streams that still have tracks ([\#2104](https://github.com/matrix-org/matrix-js-sdk/pull/2104)).
+
+Changes in [15.5.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.5.0-rc.1) (2022-01-26)
+============================================================================================================
+
+## ✨ Features
+ * Support m.asset in m.location event content ([\#2109](https://github.com/matrix-org/matrix-js-sdk/pull/2109)).
+ * Send extensible events structure and support on-demand parsing ([\#2091](https://github.com/matrix-org/matrix-js-sdk/pull/2091)).
+ * Support cancelling events whilst they are in status = ENCRYPTING ([\#2095](https://github.com/matrix-org/matrix-js-sdk/pull/2095)).
+
+## 🐛 Bug Fixes
+ * Fix http-api butchering idServer requests ([\#2134](https://github.com/matrix-org/matrix-js-sdk/pull/2134)). Fixes vector-im/element-web#20680.
+ * Don't remove streams that still have tracks ([\#2104](https://github.com/matrix-org/matrix-js-sdk/pull/2104)).
+
+Changes in [15.4.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.4.0) (2022-01-17)
+==================================================================================================
+
+## ✨ Features
+ * Don't consider alt_aliases when calculating room name ([\#2094](https://github.com/matrix-org/matrix-js-sdk/pull/2094)). Fixes vector-im/element-web#13887.
+ * Load room history if necessary when searching for MSC3089 getFileEvent() ([\#2066](https://github.com/matrix-org/matrix-js-sdk/pull/2066)).
+ * Add support for MSC3030 `/timestamp_to_event` ([\#2072](https://github.com/matrix-org/matrix-js-sdk/pull/2072)).
+
+## 🐛 Bug Fixes
+ * Stop encrypting redactions as it isn't spec compliant ([\#2098](https://github.com/matrix-org/matrix-js-sdk/pull/2098)). Fixes vector-im/element-web#20460.
+ * Fix more function typings relating to key backup ([\#2086](https://github.com/matrix-org/matrix-js-sdk/pull/2086)).
+ * Fix timeline search in MSC3089 getFileEvent() ([\#2085](https://github.com/matrix-org/matrix-js-sdk/pull/2085)).
+ * Set a `deviceId` for VoIP example and use `const`/`let` ([\#2090](https://github.com/matrix-org/matrix-js-sdk/pull/2090)). Fixes #2083. Contributed by @SimonBrandner.
+ * Fix incorrect TS return type for secret storage and key backup functions ([\#2082](https://github.com/matrix-org/matrix-js-sdk/pull/2082)).
+
+Changes in [15.4.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.4.0-rc.1) (2022-01-11)
+============================================================================================================
+
+## ✨ Features
+ * Don't consider alt_aliases when calculating room name ([\#2094](https://github.com/matrix-org/matrix-js-sdk/pull/2094)). Fixes vector-im/element-web#13887.
+ * Load room history if necessary when searching for MSC3089 getFileEvent() ([\#2066](https://github.com/matrix-org/matrix-js-sdk/pull/2066)).
+ * Add support for MSC3030 `/timestamp_to_event` ([\#2072](https://github.com/matrix-org/matrix-js-sdk/pull/2072)).
+
+## 🐛 Bug Fixes
+ * Stop encrypting redactions as it isn't spec compliant ([\#2098](https://github.com/matrix-org/matrix-js-sdk/pull/2098)). Fixes vector-im/element-web#20460.
+ * Fix more function typings relating to key backup ([\#2086](https://github.com/matrix-org/matrix-js-sdk/pull/2086)).
+ * Fix timeline search in MSC3089 getFileEvent() ([\#2085](https://github.com/matrix-org/matrix-js-sdk/pull/2085)).
+ * Set a `deviceId` for VoIP example and use `const`/`let` ([\#2090](https://github.com/matrix-org/matrix-js-sdk/pull/2090)). Fixes #2083. Contributed by @SimonBrandner.
+ * Fix incorrect TS return type for secret storage and key backup functions ([\#2082](https://github.com/matrix-org/matrix-js-sdk/pull/2082)).
+
+Changes in [15.3.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.3.0) (2021-12-20)
+==================================================================================================
+
+## ✨ Features
+ * Improve fallback key behaviour ([\#2037](https://github.com/matrix-org/matrix-js-sdk/pull/2037)).
+ * Add new room event filter fields ([\#2051](https://github.com/matrix-org/matrix-js-sdk/pull/2051)).
+ * Add method to fetch /account/whoami ([\#2046](https://github.com/matrix-org/matrix-js-sdk/pull/2046)).
+
+## 🐛 Bug Fixes
+ * Filter out falsey opts in /relations API hits ([\#2059](https://github.com/matrix-org/matrix-js-sdk/pull/2059)). Fixes vector-im/element-web#20137.
+ * Fix paginateEventTimeline resolve to boolean ([\#2054](https://github.com/matrix-org/matrix-js-sdk/pull/2054)).
+ * Fix incorrect MSC3089 typings and add null checks ([\#2049](https://github.com/matrix-org/matrix-js-sdk/pull/2049)).
+
+Changes in [15.3.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.3.0-rc.1) (2021-12-14)
+============================================================================================================
+
+## ✨ Features
+ * Improve fallback key behaviour ([\#2037](https://github.com/matrix-org/matrix-js-sdk/pull/2037)).
+ * Add new room event filter fields ([\#2051](https://github.com/matrix-org/matrix-js-sdk/pull/2051)).
+ * Add method to fetch /account/whoami ([\#2046](https://github.com/matrix-org/matrix-js-sdk/pull/2046)).
+
+## 🐛 Bug Fixes
+ * Filter out falsey opts in /relations API hits ([\#2059](https://github.com/matrix-org/matrix-js-sdk/pull/2059)). Fixes vector-im/element-web#20137.
+ * Fix paginateEventTimeline resolve to boolean ([\#2054](https://github.com/matrix-org/matrix-js-sdk/pull/2054)).
+ * Fix incorrect MSC3089 typings and add null checks ([\#2049](https://github.com/matrix-org/matrix-js-sdk/pull/2049)).
+
+Changes in [15.2.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.2.1) (2021-12-13)
+==================================================================================================
+
+ * Security release with updated version of Olm to fix https://matrix.org/blog/2021/12/03/pre-disclosure-upcoming-security-release-of-libolm-and-matrix-js-sdk
+
+Changes in [15.2.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.2.0) (2021-12-06)
+==================================================================================================
+
+## ✨ Features
+ * Remove support for `ArrayBuffer` in unstable MSC3089 `createFile()` and `createNewVersion()` and instead use same content types as handled by `MatrixClient.uploadContent()`. This enables support for Node.js. ([\#2014](https://github.com/matrix-org/matrix-js-sdk/pull/2014)).
+ * Support for password-based backup on Node.js ([\#2021](https://github.com/matrix-org/matrix-js-sdk/pull/2021)).
+ * Add optional force parameter when ensuring Olm sessions ([\#2027](https://github.com/matrix-org/matrix-js-sdk/pull/2027)).
+
+## 🐛 Bug Fixes
+ * Fix call upgrades ([\#2024](https://github.com/matrix-org/matrix-js-sdk/pull/2024)). Contributed by @SimonBrandner.
+
+Changes in [15.2.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.2.0-rc.1) (2021-11-30)
+============================================================================================================
+
+## ✨ Features
+ * Remove support for `ArrayBuffer` in unstable MSC3089 `createFile()` and `createNewVersion()` and instead use same content types as handled by `MatrixClient.uploadContent()`. This enables support for Node.js. ([\#2014](https://github.com/matrix-org/matrix-js-sdk/pull/2014)).
+ * Support for password-based backup on Node.js ([\#2021](https://github.com/matrix-org/matrix-js-sdk/pull/2021)).
+ * Add optional force parameter when ensuring Olm sessions ([\#2027](https://github.com/matrix-org/matrix-js-sdk/pull/2027)).
+
+## 🐛 Bug Fixes
+ * Fix call upgrades ([\#2024](https://github.com/matrix-org/matrix-js-sdk/pull/2024)). Contributed by @SimonBrandner.
+
+Changes in [15.1.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.1.1) (2021-11-22)
+==================================================================================================
+
+## 🐛 Bug Fixes
+ * Fix edit history being broken after editing an unencrypted event with an encrypted event ([\#2013](https://github.com/matrix-org/matrix-js-sdk/pull/2013)). Fixes vector-im/element-web#19651 and vector-im/element-web#19651. Contributed by @aaronraimist.
+ * Make events pagination responses parse threads ([\#2011](https://github.com/matrix-org/matrix-js-sdk/pull/2011)). Fixes vector-im/element-web#19587 and vector-im/element-web#19587.
+
+Changes in [15.1.1-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.1.1-rc.1) (2021-11-17)
+============================================================================================================
+
+## 🐛 Bug Fixes
+ * Fix edit history being broken after editing an unencrypted event with an encrypted event ([\#2013](https://github.com/matrix-org/matrix-js-sdk/pull/2013)). Fixes vector-im/element-web#19651 and vector-im/element-web#19651. Contributed by @aaronraimist.
+ * Make events pagination responses parse threads ([\#2011](https://github.com/matrix-org/matrix-js-sdk/pull/2011)). Fixes vector-im/element-web#19587 and vector-im/element-web#19587.
+
+Changes in [15.1.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.1.0) (2021-11-08)
+==================================================================================================
+
+## 🦖 Deprecations
+ * Mark old verification methods as deprecated ([\#1994](https://github.com/matrix-org/matrix-js-sdk/pull/1994)).
+
+## ✨ Features
+ * Try to set a sender on search result events if possible ([\#2004](https://github.com/matrix-org/matrix-js-sdk/pull/2004)).
+ * Port some changes from group calls branch to develop ([\#2001](https://github.com/matrix-org/matrix-js-sdk/pull/2001)). Contributed by @SimonBrandner.
+ * Fetch room membership from server rather than relying on stored data ([\#1998](https://github.com/matrix-org/matrix-js-sdk/pull/1998)).
+ * Add method to fetch the MSC3266 Room Summary of a Room ([\#1988](https://github.com/matrix-org/matrix-js-sdk/pull/1988)).
+
+## 🐛 Bug Fixes
+ * Don't show `Unable to access microphone` when cancelling screensharing dialog ([\#2005](https://github.com/matrix-org/matrix-js-sdk/pull/2005)). Fixes vector-im/element-web#19533 and vector-im/element-web#19533. Contributed by @SimonBrandner.
+ * Strip direction override characters from display names ([\#1992](https://github.com/matrix-org/matrix-js-sdk/pull/1992)). Fixes vector-im/element-web#1712 and vector-im/element-web#1712.
+
+Changes in [15.1.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v15.1.0-rc.1) (2021-11-02)
+============================================================================================================
+
+## 🦖 Deprecations
+ * Mark old verification methods as deprecated ([\#1994](https://github.com/matrix-org/matrix-js-sdk/pull/1994)).
+
+## ✨ Features
+ * Try to set a sender on search result events if possible ([\#2004](https://github.com/matrix-org/matrix-js-sdk/pull/2004)).
+ * Port some changes from group calls branch to develop ([\#2001](https://github.com/matrix-org/matrix-js-sdk/pull/2001)). Contributed by @SimonBrandner.
+ * Fetch room membership from server rather than relying on stored data ([\#1998](https://github.com/matrix-org/matrix-js-sdk/pull/1998)).
+ * Add method to fetch the MSC3266 Room Summary of a Room ([\#1988](https://github.com/matrix-org/matrix-js-sdk/pull/1988)).
+
+## 🐛 Bug Fixes
+ * Don't show `Unable to access microphone` when cancelling screensharing dialog ([\#2005](https://github.com/matrix-org/matrix-js-sdk/pull/2005)). Fixes vector-im/element-web#19533 and vector-im/element-web#19533. Contributed by @SimonBrandner.
+ * Strip direction override characters from display names ([\#1992](https://github.com/matrix-org/matrix-js-sdk/pull/1992)). Fixes vector-im/element-web#1712 and vector-im/element-web#1712.
+
+Changes in [15.0.0](https://github.com/vector-im/element-desktop/releases/tag/v15.0.0) (2021-10-25)
+===================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Use `ICallFeedOpts` in the `CallFeed` constructor. To construct a new `CallFeed` object you have to pass `ICallFeedOpts` e.g. `const callFeed = new CallFeed({client ([\#1964](https://github.com/matrix-org/matrix-js-sdk/pull/1964)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+
+## ✨ Features
+ * Make threads use 'm.thread' relation ([\#1980](https://github.com/matrix-org/matrix-js-sdk/pull/1980)).
+ * Try to answer a call without video if we can't access the camera  ([\#1972](https://github.com/matrix-org/matrix-js-sdk/pull/1972)). Fixes vector-im/element-web#17975 and vector-im/element-web#17975. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Make `opts` in `importRoomKeys()` optional ([\#1974](https://github.com/matrix-org/matrix-js-sdk/pull/1974)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Enable TypeScript declaration maps ([\#1966](https://github.com/matrix-org/matrix-js-sdk/pull/1966)). Contributed by [Alexendoo](https://github.com/Alexendoo).
+
+## 🐛 Bug Fixes
+ * Fix `requestVerificationDM` with chronological `pendingEventOrdering` ([\#1943](https://github.com/matrix-org/matrix-js-sdk/pull/1943)). Contributed by [freaktechnik](https://github.com/freaktechnik).
+
+Changes in [15.0.0-rc.1](https://github.com/vector-im/element-desktop/releases/tag/v15.0.0-rc.1) (2021-10-19)
+=============================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Use `ICallFeedOpts` in the `CallFeed` constructor. To construct a new `CallFeed` object you have to pass `ICallFeedOpts` e.g. `const callFeed = new CallFeed({client ([\#1964](https://github.com/matrix-org/matrix-js-sdk/pull/1964)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+
+## ✨ Features
+ * Make threads use 'm.thread' relation ([\#1980](https://github.com/matrix-org/matrix-js-sdk/pull/1980)).
+ * Try to answer a call without video if we can't access the camera  ([\#1972](https://github.com/matrix-org/matrix-js-sdk/pull/1972)). Fixes vector-im/element-web#17975 and vector-im/element-web#17975. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Make `opts` in `importRoomKeys()` optional ([\#1974](https://github.com/matrix-org/matrix-js-sdk/pull/1974)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Enable TypeScript declaration maps ([\#1966](https://github.com/matrix-org/matrix-js-sdk/pull/1966)). Contributed by [Alexendoo](https://github.com/Alexendoo).
+
+## 🐛 Bug Fixes
+ * Fix `requestVerificationDM` with chronological `pendingEventOrdering` ([\#1943](https://github.com/matrix-org/matrix-js-sdk/pull/1943)). Contributed by [freaktechnik](https://github.com/freaktechnik).
+
+Changes in [14.0.1](https://github.com/vector-im/element-desktop/releases/tag/v14.0.1) (2021-10-12)
+===================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Support for call upgrades. `setLocalVideoMuted()` and `setMicrophoneMuted()` are now `async` and return the new mute state ([\#1827](https://github.com/matrix-org/matrix-js-sdk/pull/1827)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+
+## ✨ Features
+ * Implement file versioning for tree spaces ([\#1952](https://github.com/matrix-org/matrix-js-sdk/pull/1952)).
+ * Allow answering calls without audio/video ([\#1950](https://github.com/matrix-org/matrix-js-sdk/pull/1950)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `bound` to `IThreepid` ([\#1941](https://github.com/matrix-org/matrix-js-sdk/pull/1941)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `trusted_locally` to `TrustInfo` ([\#1942](https://github.com/matrix-org/matrix-js-sdk/pull/1942)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+
+## 🐛 Bug Fixes
+ * Fix incorrect return value type in getJoinedRooms() ([\#1959](https://github.com/matrix-org/matrix-js-sdk/pull/1959)). Contributed by [psrpinto](https://github.com/psrpinto).
+ * Make sure to set `callLengthInterval` only once ([\#1958](https://github.com/matrix-org/matrix-js-sdk/pull/1958)). Fixes vector-im/element-web#19221 and vector-im/element-web#19221. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Fix event partitioning from non threading ready clients ([\#1948](https://github.com/matrix-org/matrix-js-sdk/pull/1948)).
+ * Ensure unencrypted fields get exposed by getEffectiveEvent() ([\#1938](https://github.com/matrix-org/matrix-js-sdk/pull/1938)). Fixes vector-im/element-web#19062 and vector-im/element-web#19062.
+
+
+Changes in [14.0.0-rc.1](https://github.com/vector-im/element-desktop/releases/tag/v14.0.0-rc.1) (2021-10-04)
+=============================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Support for call upgrades. `setLocalVideoMuted()` and `setMicrophoneMuted()` are now `async` and return the new mute state ([\#1827](https://github.com/matrix-org/matrix-js-sdk/pull/1827)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+
+## ✨ Features
+ * Implement file versioning for tree spaces ([\#1952](https://github.com/matrix-org/matrix-js-sdk/pull/1952)).
+ * Allow answering calls without audio/video ([\#1950](https://github.com/matrix-org/matrix-js-sdk/pull/1950)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `bound` to `IThreepid` ([\#1941](https://github.com/matrix-org/matrix-js-sdk/pull/1941)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `trusted_locally` to `TrustInfo` ([\#1942](https://github.com/matrix-org/matrix-js-sdk/pull/1942)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+
+## 🐛 Bug Fixes
+ * Fix incorrect return value type in getJoinedRooms() ([\#1959](https://github.com/matrix-org/matrix-js-sdk/pull/1959)). Contributed by [psrpinto](https://github.com/psrpinto).
+ * Make sure to set `callLengthInterval` only once ([\#1958](https://github.com/matrix-org/matrix-js-sdk/pull/1958)). Fixes vector-im/element-web#19221 and vector-im/element-web#19221. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Fix event partitioning from non threading ready clients ([\#1948](https://github.com/matrix-org/matrix-js-sdk/pull/1948)).
+ * Ensure unencrypted fields get exposed by getEffectiveEvent() ([\#1938](https://github.com/matrix-org/matrix-js-sdk/pull/1938)). Fixes vector-im/element-web#19062 and vector-im/element-web#19062.
+
+Changes in [13.0.0](https://github.com/vector-im/element-desktop/releases/tag/v13.0.0) (2021-09-27)
+===================================================================================================
+
+## ✨ Features
+ * Add `getHistoryVisibility()` and `getGuestAccess()` ([\#1940](https://github.com/matrix-org/matrix-js-sdk/pull/1940)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `getBuffer()` to `QRCodeData` ([\#1927](https://github.com/matrix-org/matrix-js-sdk/pull/1927)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Added `createDataChannel()` and `CallEvent.DataChannel` to `MatrixCall` for creating and listening for WebRTC datachannels. ([\#1929](https://github.com/matrix-org/matrix-js-sdk/pull/1929)). Contributed by [robertlong](https://github.com/robertlong).
+ * Add file locking to MSC3089 branches ([\#1909](https://github.com/matrix-org/matrix-js-sdk/pull/1909)).
+ * Add `hasBeenCancelled` to `VerificationBase` ([\#1915](https://github.com/matrix-org/matrix-js-sdk/pull/1915)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `ISasEvent` ([\#1908](https://github.com/matrix-org/matrix-js-sdk/pull/1908)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Count notifications in encrypted rooms client-side ([\#1872](https://github.com/matrix-org/matrix-js-sdk/pull/1872)). Fixes vector-im/element-web#15393 and vector-im/element-web#15393. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Exclude opt-in Element performance metrics from encryption ([\#1897](https://github.com/matrix-org/matrix-js-sdk/pull/1897)).
+
+## 🐛 Bug Fixes
+ * Fix race on automatic backup restore ([\#1936](https://github.com/matrix-org/matrix-js-sdk/pull/1936)). Fixes vector-im/element-web#17781 and vector-im/element-web#17781.
+
+Changes in [13.0.0-rc.1](https://github.com/vector-im/element-desktop/releases/tag/v13.0.0-rc.1) (2021-09-21)
+=============================================================================================================
+
+## ✨ Features
+ * Add `getHistoryVisibility()` and `getGuestAccess()` ([\#1940](https://github.com/matrix-org/matrix-js-sdk/pull/1940)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `getBuffer()` to `QRCodeData` ([\#1927](https://github.com/matrix-org/matrix-js-sdk/pull/1927)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Added `createDataChannel()` and `CallEvent.DataChannel` to `MatrixCall` for creating and listening for WebRTC datachannels. ([\#1929](https://github.com/matrix-org/matrix-js-sdk/pull/1929)). Contributed by [robertlong](https://github.com/robertlong).
+ * Add file locking to MSC3089 branches ([\#1909](https://github.com/matrix-org/matrix-js-sdk/pull/1909)).
+ * Add `hasBeenCancelled` to `VerificationBase` ([\#1915](https://github.com/matrix-org/matrix-js-sdk/pull/1915)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Add `ISasEvent` ([\#1908](https://github.com/matrix-org/matrix-js-sdk/pull/1908)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Count notifications in encrypted rooms client-side ([\#1872](https://github.com/matrix-org/matrix-js-sdk/pull/1872)). Fixes vector-im/element-web#15393 and vector-im/element-web#15393. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Exclude opt-in Element performance metrics from encryption ([\#1897](https://github.com/matrix-org/matrix-js-sdk/pull/1897)).
+
+## 🐛 Bug Fixes
+ * Fix race on automatic backup restore ([\#1936](https://github.com/matrix-org/matrix-js-sdk/pull/1936)). Fixes vector-im/element-web#17781 and vector-im/element-web#17781.
+
+Changes in [12.5.0](https://github.com/vector-im/element-desktop/releases/tag/v12.5.0) (2021-09-14)
+===================================================================================================
+
+## ✨ Features
+ * [Release] Exclude opt-in Element performance metrics from encryption ([\#1901](https://github.com/matrix-org/matrix-js-sdk/pull/1901)).
+ * Give `MatrixCall` the capability to emit `LengthChanged` events ([\#1873](https://github.com/matrix-org/matrix-js-sdk/pull/1873)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Improve browser example ([\#1875](https://github.com/matrix-org/matrix-js-sdk/pull/1875)). Contributed by [psrpinto](https://github.com/psrpinto).
+ * Give `CallFeed` the capability to emit on volume changes ([\#1865](https://github.com/matrix-org/matrix-js-sdk/pull/1865)). Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+
+## 🐛 Bug Fixes
+ * Fix verification request cancellation ([\#1871](https://github.com/matrix-org/matrix-js-sdk/pull/1871)).
+
+Changes in [12.4.1](https://github.com/vector-im/element-desktop/releases/tag/v12.4.1) (2021-09-13)
+===================================================================================================
+
+## 🔒 SECURITY FIXES
+ * Fix a security issue with message key sharing. See https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing
+   for details.
+
+Changes in [12.4.0](https://github.com/vector-im/element-desktop/releases/tag/v12.4.0) (2021-08-31)
+===================================================================================================
+
+## 🦖 Deprecations
+ * Deprecate groups APIs. Groups are no longer supported, only Synapse has support. They are being replaced by Spaces which build off of Rooms and are far more flexible. ([\#1792](https://github.com/matrix-org/matrix-js-sdk/pull/1792)).
+
+## ✨ Features
+ * Add method for including extra fields when uploading to a tree space ([\#1850](https://github.com/matrix-org/matrix-js-sdk/pull/1850)).
+
+## 🐛 Bug Fixes
+ * Fix broken voice calls, no ringing and broken call notifications ([\#1858](https://github.com/matrix-org/matrix-js-sdk/pull/1858)). Fixes vector-im/element-web#18578 vector-im/element-web#18538 and vector-im/element-web#18578. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Revert "Fix glare related regressions" ([\#1857](https://github.com/matrix-org/matrix-js-sdk/pull/1857)).
+ * Fix glare related regressions ([\#1851](https://github.com/matrix-org/matrix-js-sdk/pull/1851)). Fixes vector-im/element-web#18538 and vector-im/element-web#18538. Contributed by [SimonBrandner](https://github.com/SimonBrandner).
+ * Fix temporary call messages being handled without call  ([\#1834](https://github.com/matrix-org/matrix-js-sdk/pull/1834)). Contributed by [Palid](https://github.com/Palid).
+ * Fix conditional on returning file tree spaces ([\#1841](https://github.com/matrix-org/matrix-js-sdk/pull/1841)).
+
 Changes in [12.3.1](https://github.com/vector-im/element-desktop/releases/tag/v12.3.1) (2021-08-17)
 ===================================================================================================

@@ -22,8 +22,14 @@ ask you to make any refinements needed or merge it and make them ourselves.
 Things that should go into your PR description:
 * A changelog entry in the `Notes` section (see below)
 * References to any bugs fixed by the change (in GitHub's `Fixes` notation)
- * Notes for the reviewer that might help them to understand why the change is
-   necessary or how they might better review it.
+ * Describe the why and what is changing in the PR description so it's easy for
+   onlookers and reviewers to onboard and context switch.
+ * Include both **before** and **after** screenshots to easily compare and discuss
+   what's changing.
+ * Include a step-by-step testing strategy so that a reviewer can check out the
+   code locally and easily get to the point of testing your change.
+ * Add comments to the diff for the reviewer that might help them to understand
+   why the change is necessary or how they might better understand and review it.

 Things that should *not* go into your PR description:
 * Any information on how the code works or why you chose to do it the way
@@ -92,6 +98,21 @@ We use continuous integration, and all pull requests get automatically tested:
 if your change breaks the build, then the PR will show that there are failed
 checks, so please check back after a few minutes.

+Tests
+-----
+If your PR is a feature (ie. if it's being labelled with the 'T-Enhancement'
+label) then we require that the PR also includes tests. These need to test that
+your feature works as expected and ideally test edge cases too. For the js-sdk
+itself, your tests should generally be unit tests. matrix-react-sdk also uses
+these guidelines, so for that your tests can be unit tests using
+react-test-utils, snapshot tests or screenshot tests.
+
+We don't require tests for bug fixes (T-Defect) but strongly encourage regression
+tests for the bug itself wherever possible.
+
+In the future we may formalise this more with a minimum test coverage
+percentage for the diff.
+
 Code style
 ----------
 The js-sdk aims to target TypeScript/ES6. All new files should be written in
@@ -1,6 +1,6 @@
 console.log("Loading browser sdk");

-var client = matrixcs.createClient("http://matrix.org");
+var client = matrixcs.createClient("https://matrix.org");
 client.publicRooms(function (err, data) {
    if (err) {
 	   console.error("err %s", JSON.stringify(err));
@@ -1,6 +1,8 @@
-<html>
+<html lang="en">
 <head>
 <title>Test</title>
+<meta charset="utf-8"/>
+<link rel="icon" href="data:,">
 <script src="lib/matrix.js"></script>
 <script src="browserTest.js"></script>
 </head>
@@ -1,16 +1,17 @@
 console.log("Loading browser sdk");
-var BASE_URL = "https://matrix.org";
-var TOKEN = "accesstokengoeshere";
-var USER_ID = "@username:localhost";
-var ROOM_ID = "!room:id";
+const BASE_URL = "https://matrix.org";
+const TOKEN = "accesstokengoeshere";
+const USER_ID = "@username:localhost";
+const ROOM_ID = "!room:id";
+const DEVICE_ID = "some_device_id";

-
-var client = matrixcs.createClient({
+const client = matrixcs.createClient({
    baseUrl: BASE_URL,
    accessToken: TOKEN,
-    userId: USER_ID
+    userId: USER_ID,
+    deviceId: DEVICE_ID
 });
-var call;
+let call;

 function disableButtons(place, answer, hangup) {
    document.getElementById("hangup").disabled = hangup;
@@ -19,7 +20,7 @@ function disableButtons(place, answer, hangup) {
 }

 function addListeners(call) {
-    var lastError = "";
+    let lastError = "";
    call.on("hangup", function() {
        disableButtons(false, true, true);
        document.getElementById("result").innerHTML = (
@@ -1,6 +1,6 @@
 {
  "name": "matrix-js-sdk",
-  "version": "12.3.1",
+  "version": "16.0.0",
  "description": "Matrix Client-Server SDK for Javascript",
  "scripts": {
    "prepublishOnly": "yarn build",
@@ -15,7 +15,7 @@
    "build:minify-browser": "terser dist/browser-matrix.js --compress --mangle --source-map --output dist/browser-matrix.min.js",
    "gendoc": "jsdoc -c jsdoc.json -P package.json",
    "lint": "yarn lint:types && yarn lint:js",
-    "lint:js": "eslint --max-warnings 7 src spec",
+    "lint:js": "eslint --max-warnings 0 src spec",
    "lint:js-fix": "eslint --fix src spec",
    "lint:types": "tsc --noEmit",
    "test": "jest",
@@ -56,6 +56,7 @@
    "bs58": "^4.0.1",
    "content-type": "^1.0.4",
    "loglevel": "^1.7.1",
+    "matrix-events-sdk": "^0.0.1-beta.7",
    "p-retry": "^4.5.0",
    "qs": "^6.9.6",
    "request": "^2.88.2",
@@ -74,22 +75,24 @@
    "@babel/preset-env": "^7.12.11",
    "@babel/preset-typescript": "^7.12.7",
    "@babel/register": "^7.12.10",
-    "@matrix-org/olm": "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.3.tgz",
+    "@matrix-org/olm": "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.8.tgz",
    "@types/bs58": "^4.0.1",
+    "@types/content-type": "^1.1.5",
    "@types/jest": "^26.0.20",
    "@types/node": "12",
    "@types/request": "^2.48.5",
-    "@typescript-eslint/eslint-plugin": "^4.17.0",
-    "@typescript-eslint/parser": "^4.17.0",
-    "allchange": "^1.0.0",
+    "@typescript-eslint/eslint-plugin": "^5.6.0",
+    "@typescript-eslint/parser": "^5.6.0",
+    "allchange": "^1.0.6",
    "babel-jest": "^26.6.3",
    "babelify": "^10.0.0",
    "better-docs": "^2.4.0-beta.9",
    "browserify": "^17.0.0",
    "docdash": "^1.2.0",
-    "eslint": "7.18.0",
+    "eslint": "8.9.0",
    "eslint-config-google": "^0.14.0",
-    "eslint-plugin-matrix-org": "github:matrix-org/eslint-plugin-matrix-org#2306b3d4da4eba908b256014b979f1d3d43d2945",
+    "eslint-plugin-import": "^2.25.4",
+    "eslint-plugin-matrix-org": "^0.4.0",
    "exorcist": "^1.0.1",
    "fake-indexeddb": "^3.1.2",
    "jest": "^26.6.3",
@@ -99,7 +102,7 @@
    "rimraf": "^3.0.2",
    "terser": "^5.5.1",
    "tsify": "^5.0.2",
-    "typescript": "^4.1.3"
+    "typescript": "^4.5.3"
  },
  "jest": {
    "testEnvironment": "node",
@@ -110,7 +113,8 @@
      "<rootDir>/src/**/*.{js,ts}"
    ],
    "coverageReporters": [
-      "text"
+      "text",
+      "json"
    ]
  },
  "typings": "./lib/index.d.ts"
@@ -255,6 +255,12 @@ if [ -n "$signing_id" ]; then
    # the easiest way to check the validity of the tarball from git is to unzip
    # it and compare it with our own idea of what the tar should look like.

+    # This uses git archive which seems to be what github uses. Specifically,
+    # the header fields are set in the same way: same file mode, uid & gid
+    # both zero and mtime set to the timestamp of the commit that the tag
+    # references. Also note that this puts the commit into the tar headers
+    # and can be extracted with gunzip -c foo.tar.gz | git get-tar-commit-id
+
    # the name of the sig file we want to create
    source_sigfile="${tag}-src.tar.gz.asc"

@@ -20,6 +20,7 @@ limitations under the License.
 import './olm-loader';

 import MockHttpBackend from 'matrix-mock-request';
+
 import { LocalStorageCryptoStore } from '../src/crypto/store/localStorage-crypto-store';
 import { logger } from '../src/logger';
 import { WebStorageSessionStore } from "../src/store/session/webstorage";
@@ -85,6 +86,7 @@ TestClient.prototype.toString = function() {
 */
 TestClient.prototype.start = function() {
    logger.log(this + ': starting');
+    this.httpBackend.when("GET", "/capabilities").respond(200, { capabilities: {} });
    this.httpBackend.when("GET", "/pushrules").respond(200, {});
    this.httpBackend.when("POST", "/filter").respond(200, { filter_id: "fid" });
    this.expectDeviceKeyUpload();
@@ -17,54 +17,34 @@ limitations under the License.
 // load XmlHttpRequest mock
 import "./setupTests";
 import "../../dist/browser-matrix"; // uses browser-matrix instead of the src
-import { MockStorageApi } from "../MockStorageApi";
-import { WebStorageSessionStore } from "../../src/store/session/webstorage";
-import MockHttpBackend from "matrix-mock-request";
-import { LocalStorageCryptoStore } from "../../src/crypto/store/localStorage-crypto-store";
 import * as utils from "../test-utils";
+import { TestClient } from "../TestClient";

 const USER_ID = "@user:test.server";
 const DEVICE_ID = "device_id";
 const ACCESS_TOKEN = "access_token";
 const ROOM_ID = "!room_id:server.test";

-/* global matrixcs */
-
 describe("Browserify Test", function() {
    let client;
    let httpBackend;

-    async function createTestClient() {
-        const sessionStoreBackend = new MockStorageApi();
-        const sessionStore = new WebStorageSessionStore(sessionStoreBackend);
-        const httpBackend = new MockHttpBackend();
+    beforeEach(() => {
+        const testClient = new TestClient(USER_ID, DEVICE_ID, ACCESS_TOKEN);

-        const options = {
-            baseUrl: "http://" + USER_ID + ".test.server",
-            userId: USER_ID,
-            accessToken: ACCESS_TOKEN,
-            deviceId: DEVICE_ID,
-            sessionStore: sessionStore,
-            request: httpBackend.requestFn,
-            cryptoStore: new LocalStorageCryptoStore(sessionStoreBackend),
-        };
-
-        const client = matrixcs.createClient(options);
+        client = testClient.client;
+        httpBackend = testClient.httpBackend;

+        httpBackend.when("GET", "/capabilities").respond(200, { capabilities: {} });
        httpBackend.when("GET", "/pushrules").respond(200, {});
        httpBackend.when("POST", "/filter").respond(200, { filter_id: "fid" });

-        return { client, httpBackend };
-    }
-
-    beforeEach(async () => {
-        ({ client, httpBackend } = await createTestClient());
-        await client.startClient();
+        client.startClient();
    });

    afterEach(async () => {
        client.stopClient();
-        await httpBackend.stop();
+        httpBackend.stop();
    });

    it("Sync", async function() {
@@ -91,10 +71,8 @@ describe("Browserify Test", function() {
        };

        httpBackend.when("GET", "/sync").respond(200, syncData);
-        await Promise.race([
-            Promise.all([
-                httpBackend.flushAllExpected(),
-            ]),
+        return await Promise.race([
+            httpBackend.flushAllExpected(),
            new Promise((_, reject) => {
                client.once("sync.unexpectedError", reject);
            }),
@@ -348,7 +348,7 @@ function recvMessage(httpBackend, client, sender, message) {
        return testUtils.awaitDecryption(event);
    }).then((event) => {
        expect(event.getType()).toEqual("m.room.message");
-        expect(event.getContent()).toEqual({
+        expect(event.getContent()).toMatchObject({
            msgtype: "m.text",
            body: "Hello, World",
        });
@@ -722,6 +722,7 @@ describe("MatrixClient crypto", function() {
        return Promise.resolve()
            .then(() => {
                logger.log(aliTestClient + ': starting');
+                httpBackend.when("GET", "/capabilities").respond(200, {});
                httpBackend.when("GET", "/pushrules").respond(200, {});
                httpBackend.when("POST", "/filter").respond(200, { filter_id: "fid" });
                aliTestClient.expectDeviceKeyUpload();
@@ -13,6 +13,7 @@ describe("MatrixClient events", function() {
        httpBackend = testClient.httpBackend;
        httpBackend.when("GET", "/pushrules").respond(200, {});
        httpBackend.when("POST", "/filter").respond(200, { filter_id: "a filter id" });
+        httpBackend.when("GET", "/capabilities").respond(200, { capabilities: {} });
    });

    afterEach(function() {
@@ -71,6 +71,7 @@ const EVENTS = [

 // start the client, and wait for it to initialise
 function startClient(httpBackend, client) {
+    httpBackend.when("GET", "/capabilities").respond(200, { capabilities: {} });
    httpBackend.when("GET", "/pushrules").respond(200, {});
    httpBackend.when("POST", "/filter").respond(200, { filter_id: "fid" });
    httpBackend.when("GET", "/sync").respond(200, INITIAL_SYNC_DATA);
@@ -502,7 +503,7 @@ describe("MatrixClient event timelines", function() {
                    const params = req.queryParams;
                    expect(params.dir).toEqual("b");
                    expect(params.from).toEqual("start_token0");
-                    expect(params.limit).toEqual(30);
+                    expect(params.limit).toEqual("30");
                }).respond(200, function() {
                    return {
                        chunk: [EVENTS[1], EVENTS[2]],
@@ -553,7 +554,7 @@ describe("MatrixClient event timelines", function() {
                    const params = req.queryParams;
                    expect(params.dir).toEqual("f");
                    expect(params.from).toEqual("end_token0");
-                    expect(params.limit).toEqual(20);
+                    expect(params.limit).toEqual("20");
                }).respond(200, function() {
                    return {
                        chunk: [EVENTS[1], EVENTS[2]],
@@ -1,5 +1,6 @@
 import * as utils from "../test-utils";
 import { CRYPTO_ENABLED } from "../../src/client";
+import { MatrixEvent } from "../../src/models/event";
 import { Filter, MemoryStore, Room } from "../../src/matrix";
 import { TestClient } from "../TestClient";

@@ -392,6 +393,414 @@ describe("MatrixClient", function() {
            return prom;
        });
    });
+
+    describe("partitionThreadedEvents", function() {
+        it("returns empty arrays when given an empty arrays", function() {
+            const events = [];
+            const [timeline, threaded] = client.partitionThreadedEvents(events);
+            expect(timeline).toEqual([]);
+            expect(threaded).toEqual([]);
+        });
+
+        it("copies pre-thread in-timeline vote events onto both timelines", function() {
+            client.clientOpts = { experimentalThreadSupport: true };
+
+            const eventMessageInThread = buildEventMessageInThread();
+            const eventPollResponseReference = buildEventPollResponseReference();
+            const eventPollStartThreadRoot = buildEventPollStartThreadRoot();
+
+            const events = [
+                eventMessageInThread,
+                eventPollResponseReference,
+                eventPollStartThreadRoot,
+            ];
+            // Vote has no threadId yet
+            expect(eventPollResponseReference.threadId).toBeFalsy();
+
+            const [timeline, threaded] = client.partitionThreadedEvents(events);
+
+            expect(timeline).toEqual([
+                // The message that was sent in a thread is missing
+                eventPollResponseReference,
+                eventPollStartThreadRoot,
+            ]);
+
+            // The vote event has been copied into the thread
+            const eventRefWithThreadId = withThreadId(
+                eventPollResponseReference, eventPollStartThreadRoot.getId());
+            expect(eventRefWithThreadId.threadId).toBeTruthy();
+
+            expect(threaded).toEqual([
+                eventMessageInThread,
+                eventRefWithThreadId,
+                // Thread does not see thread root
+            ]);
+        });
+
+        it("copies pre-thread in-timeline reactions onto both timelines", function() {
+            client.clientOpts = { experimentalThreadSupport: true };
+
+            const eventMessageInThread = buildEventMessageInThread();
+            const eventReaction = buildEventReaction();
+            const eventPollStartThreadRoot = buildEventPollStartThreadRoot();
+
+            const events = [
+                eventMessageInThread,
+                eventReaction,
+                eventPollStartThreadRoot,
+            ];
+
+            const [timeline, threaded] = client.partitionThreadedEvents(events);
+
+            expect(timeline).toEqual([
+                eventReaction,
+                eventPollStartThreadRoot,
+            ]);
+
+            expect(threaded).toEqual([
+                eventMessageInThread,
+                withThreadId(eventReaction, eventPollStartThreadRoot.getId()),
+            ]);
+        });
+
+        it("copies post-thread in-timeline vote events onto both timelines", function() {
+            client.clientOpts = { experimentalThreadSupport: true };
+
+            const eventPollResponseReference = buildEventPollResponseReference();
+            const eventMessageInThread = buildEventMessageInThread();
+            const eventPollStartThreadRoot = buildEventPollStartThreadRoot();
+
+            const events = [
+                eventPollResponseReference,
+                eventMessageInThread,
+                eventPollStartThreadRoot,
+            ];
+
+            const [timeline, threaded] = client.partitionThreadedEvents(events);
+
+            expect(timeline).toEqual([
+                eventPollResponseReference,
+                eventPollStartThreadRoot,
+            ]);
+
+            expect(threaded).toEqual([
+                withThreadId(eventPollResponseReference, eventPollStartThreadRoot.getId()),
+                eventMessageInThread,
+            ]);
+        });
+
+        it("copies post-thread in-timeline reactions onto both timelines", function() {
+            client.clientOpts = { experimentalThreadSupport: true };
+
+            const eventReaction = buildEventReaction();
+            const eventMessageInThread = buildEventMessageInThread();
+            const eventPollStartThreadRoot = buildEventPollStartThreadRoot();
+
+            const events = [
+                eventReaction,
+                eventMessageInThread,
+                eventPollStartThreadRoot,
+            ];
+
+            const [timeline, threaded] = client.partitionThreadedEvents(events);
+
+            expect(timeline).toEqual([
+                eventReaction,
+                eventPollStartThreadRoot,
+            ]);
+
+            expect(threaded).toEqual([
+                withThreadId(eventReaction, eventPollStartThreadRoot.getId()),
+                eventMessageInThread,
+            ]);
+        });
+
+        it("sends room state events to the main timeline only", function() {
+            client.clientOpts = { experimentalThreadSupport: true };
+            // This is based on recording the events in a real room:
+
+            const eventMessageInThread = buildEventMessageInThread();
+            const eventPollResponseReference = buildEventPollResponseReference();
+            const eventPollStartThreadRoot = buildEventPollStartThreadRoot();
+            const eventRoomName = buildEventRoomName();
+            const eventEncryption = buildEventEncryption();
+            const eventGuestAccess = buildEventGuestAccess();
+            const eventHistoryVisibility = buildEventHistoryVisibility();
+            const eventJoinRules = buildEventJoinRules();
+            const eventPowerLevels = buildEventPowerLevels();
+            const eventMember = buildEventMember();
+            const eventCreate = buildEventCreate();
+
+            const events = [
+                eventMessageInThread,
+                eventPollResponseReference,
+                eventPollStartThreadRoot,
+                eventRoomName,
+                eventEncryption,
+                eventGuestAccess,
+                eventHistoryVisibility,
+                eventJoinRules,
+                eventPowerLevels,
+                eventMember,
+                eventCreate,
+            ];
+            const [timeline, threaded] = client.partitionThreadedEvents(events);
+
+            expect(timeline).toEqual([
+                // The message that was sent in a thread is missing
+                eventPollResponseReference,
+                eventPollStartThreadRoot,
+                eventRoomName,
+                eventEncryption,
+                eventGuestAccess,
+                eventHistoryVisibility,
+                eventJoinRules,
+                eventPowerLevels,
+                eventMember,
+                eventCreate,
+            ]);
+
+            // Thread should contain only stuff that happened in the thread -
+            // no thread root, and no room state events
+            expect(threaded).toEqual([
+                eventMessageInThread,
+                withThreadId(eventPollResponseReference, eventPollStartThreadRoot.getId()),
+            ]);
+        });
+    });
+});
+
+function withThreadId(event, newThreadId) {
+    const ret = event.toSnapshot();
+    ret.setThreadId(newThreadId);
+    return ret;
+}
+
+const buildEventMessageInThread = () => new MatrixEvent({
+    "age": 80098509,
+    "content": {
+        "algorithm": "m.megolm.v1.aes-sha2",
+        "ciphertext": "ENCRYPTEDSTUFF",
+        "device_id": "XISFUZSKHH",
+        "m.relates_to": {
+            "event_id": "$VLS2ojbPmxb6x8ECetn45hmND6cRDcjgv-j-to9m7Vo",
+            "m.in_reply_to": {
+                "event_id": "$VLS2ojbPmxb6x8ECetn45hmND6cRDcjgv-j-to9m7Vo",
+            },
+            "rel_type": "io.element.thread",
+        },
+        "sender_key": "i3N3CtG/CD2bGB8rA9fW6adLYSDvlUhf2iuU73L65Vg",
+        "session_id": "Ja11R/KG6ua0wdk8zAzognrxjio1Gm/RK2Gn6lFL804",
+    },
+    "event_id": "$W4chKIGYowtBblVLkRimeIg8TcdjETnxhDPGfi6NpDg",
+    "origin_server_ts": 1643815466378,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "type": "m.room.encrypted",
+    "unsigned": { "age": 80098509 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventPollResponseReference = () => new MatrixEvent({
+    "age": 80098509,
+    "content": {
+        "algorithm": "m.megolm.v1.aes-sha2",
+        "ciphertext": "ENCRYPTEDSTUFF",
+        "device_id": "XISFUZSKHH",
+        "m.relates_to": {
+            "event_id": "$VLS2ojbPmxb6x8ECetn45hmND6cRDcjgv-j-to9m7Vo",
+            "rel_type": "m.reference",
+        },
+        "sender_key": "i3N3CtG/CD2bGB8rA9fW6adLYSDvlUhf2iuU73L65Vg",
+        "session_id": "Ja11R/KG6ua0wdk8zAzognrxjio1Gm/RK2Gn6lFL804",
+    },
+    "event_id": "$91JvpezvsF0cKgav3g8W-uEVS4WkDHgxbJZvL3uMR1g",
+    "origin_server_ts": 1643815458650,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "type": "m.room.encrypted",
+    "unsigned": { "age": 80106237 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventReaction = () => new MatrixEvent({
+    "content": {
+        "m.relates_to": {
+            "event_id": "$VLS2ojbPmxb6x8ECetn45hmND6cRDcjgv-j-to9m7Vo",
+            "key": "🤗",
+            "rel_type": "m.annotation",
+        },
+    },
+    "origin_server_ts": 1643977249238,
+    "sender": "@andybalaam-test1:matrix.org",
+    "type": "m.reaction",
+    "unsigned": {
+        "age": 22598,
+        "transaction_id": "m1643977249073.16",
+    },
+    "event_id": "$86B2b-x3LgE4DlV4y24b7UHnt72LIA3rzjvMysTtAfA",
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+});
+
+const buildEventPollStartThreadRoot = () => new MatrixEvent({
+    "age": 80108647,
+    "content": {
+        "algorithm": "m.megolm.v1.aes-sha2",
+        "ciphertext": "ENCRYPTEDSTUFF",
+        "device_id": "XISFUZSKHH",
+        "sender_key": "i3N3CtG/CD2bGB8rA9fW6adLYSDvlUhf2iuU73L65Vg",
+        "session_id": "Ja11R/KG6ua0wdk8zAzognrxjio1Gm/RK2Gn6lFL804",
+    },
+    "event_id": "$VLS2ojbPmxb6x8ECetn45hmND6cRDcjgv-j-to9m7Vo",
+    "origin_server_ts": 1643815456240,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "type": "m.room.encrypted",
+    "unsigned": { "age": 80108647 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventRoomName = () => new MatrixEvent({
+    "age": 80123249,
+    "content": {
+        "name": "1 poll, 1 vote, 1 thread",
+    },
+    "event_id": "$QAdyNJtKnl1j7or2yMycbOCvb6bCgvHs5lg3ZMd5xWk",
+    "origin_server_ts": 1643815441638,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "",
+    "type": "m.room.name",
+    "unsigned": { "age": 80123249 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventEncryption = () => new MatrixEvent({
+    "age": 80123383,
+    "content": {
+        "algorithm": "m.megolm.v1.aes-sha2",
+    },
+    "event_id": "$1hGykogKQkXbHw8bVuyE3BjHnFBEJBcUWnakd0ck2K0",
+    "origin_server_ts": 1643815441504,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "",
+    "type": "m.room.encryption",
+    "unsigned": { "age": 80123383 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventGuestAccess = () => new MatrixEvent({
+    "age": 80123473,
+    "content": {
+        "guest_access": "can_join",
+    },
+    "event_id": "$4_2n-H6K9-0nPbnjjtIue2SU44tGJsnuTmi6UuSrh-U",
+    "origin_server_ts": 1643815441414,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "",
+    "type": "m.room.guest_access",
+    "unsigned": { "age": 80123473 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventHistoryVisibility = () => new MatrixEvent({
+    "age": 80123556,
+    "content": {
+        "history_visibility": "shared",
+    },
+    "event_id": "$W6kp44CTnvciOiHSPyhp8dh4n2v1_9kclUPddeaQj0E",
+    "origin_server_ts": 1643815441331,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "",
+    "type": "m.room.history_visibility",
+    "unsigned": { "age": 80123556 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventJoinRules = () => new MatrixEvent({
+    "age": 80123696,
+    "content": {
+        "join_rule": "invite",
+    },
+    "event_id": "$6JDDeDp7fEc0F6YnTWMruNcKWFltR3e9wk7wWDDJrAU",
+    "origin_server_ts": 1643815441191,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "",
+    "type": "m.room.join_rules",
+    "unsigned": { "age": 80123696 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventPowerLevels = () => new MatrixEvent({
+    "age": 80124105,
+    "content": {
+        "ban": 50,
+        "events": {
+            "m.room.avatar": 50,
+            "m.room.canonical_alias": 50,
+            "m.room.encryption": 100,
+            "m.room.history_visibility": 100,
+            "m.room.name": 50,
+            "m.room.power_levels": 100,
+            "m.room.server_acl": 100,
+            "m.room.tombstone": 100,
+        },
+        "events_default": 0,
+        "historical": 100,
+        "invite": 0,
+        "kick": 50,
+        "redact": 50,
+        "state_default": 50,
+        "users": {
+            "@andybalaam-test1:matrix.org": 100,
+        },
+        "users_default": 0,
+    },
+    "event_id": "$XZY2YgQhXskpc7gmJJG3S0VmS9_QjjCUVeeFTfgfC2E",
+    "origin_server_ts": 1643815440782,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "",
+    "type": "m.room.power_levels",
+    "unsigned": { "age": 80124105 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventMember = () => new MatrixEvent({
+    "age": 80125279,
+    "content": {
+        "avatar_url": "mxc://matrix.org/aNtbVcFfwotudypZcHsIcPOc",
+        "displayname": "andybalaam-test1",
+        "membership": "join",
+    },
+    "event_id": "$Ex5eVmMs_ti784mo8bgddynbwLvy6231lCycJr7Cl9M",
+    "origin_server_ts": 1643815439608,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "@andybalaam-test1:matrix.org",
+    "type": "m.room.member",
+    "unsigned": { "age": 80125279 },
+    "user_id": "@andybalaam-test1:matrix.org",
+});
+
+const buildEventCreate = () => new MatrixEvent({
+    "age": 80126105,
+    "content": {
+        "creator": "@andybalaam-test1:matrix.org",
+        "room_version": "6",
+    },
+    "event_id": "$e7j2Gt37k5NPwB6lz2N3V9lO5pUdNK8Ai7i2FPEK-oI",
+    "origin_server_ts": 1643815438782,
+    "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
+    "sender": "@andybalaam-test1:matrix.org",
+    "state_key": "",
+    "type": "m.room.create",
+    "unsigned": { "age": 80126105 },
+    "user_id": "@andybalaam-test1:matrix.org",
 });

 function assertObjectContains(obj, expected) {
@@ -1,5 +1,6 @@
-import * as utils from "../test-utils";
 import HttpBackend from "matrix-mock-request";
+
+import * as utils from "../test-utils";
 import { MatrixClient } from "../../src/matrix";
 import { MatrixScheduler } from "../../src/scheduler";
 import { MemoryStore } from "../../src/store/memory";
@@ -104,10 +105,12 @@ describe("MatrixClient opts", function() {
                    expectedEventTypes.indexOf(event.getType()), 1,
                );
            });
+            httpBackend.when("GET", "/capabilities").respond(200, { capabilities: {} });
            httpBackend.when("GET", "/pushrules").respond(200, {});
            httpBackend.when("POST", "/filter").respond(200, { filter_id: "foo" });
            httpBackend.when("GET", "/sync").respond(200, syncData);
-            await client.startClient();
+            client.startClient();
+            await httpBackend.flush("/capabilities", 1);
            await httpBackend.flush("/pushrules", 1);
            await httpBackend.flush("/filter", 1);
            await Promise.all([
@@ -1,16 +1,16 @@
-import { EventStatus } from "../../src/matrix";
+import { EventStatus, RoomEvent } from "../../src/matrix";
 import { MatrixScheduler } from "../../src/scheduler";
 import { Room } from "../../src/models/room";
 import { TestClient } from "../TestClient";

 describe("MatrixClient retrying", function() {
-    let client = null;
-    let httpBackend = null;
+    let client: TestClient = null;
+    let httpBackend: TestClient["httpBackend"] = null;
    let scheduler;
    const userId = "@alice:localhost";
    const accessToken = "aseukfgwef";
    const roomId = "!room:here";
-    let room;
+    let room: Room;

    beforeEach(function() {
        scheduler = new MatrixScheduler();
@@ -23,7 +23,7 @@ describe("MatrixClient retrying", function() {
        );
        httpBackend = testClient.httpBackend;
        client = testClient.client;
-        room = new Room(roomId);
+        room = new Room(roomId, client, userId);
        client.store.storeRoom(room);
    });

@@ -50,17 +50,23 @@ describe("MatrixClient retrying", function() {

    it("should mark events as EventStatus.CANCELLED when cancelled", function() {
        // send a couple of events; the second will be queued
-        const p1 = client.sendMessage(roomId, "m1").then(function(ev) {
+        const p1 = client.sendMessage(roomId, {
+            "msgtype": "m.text",
+            "body": "m1",
+        }).then(function() {
            // we expect the first message to fail
            throw new Error('Message 1 unexpectedly sent successfully');
-        }, (e) => {
+        }, () => {
            // this is expected
        });

        // XXX: it turns out that the promise returned by this message
        // never gets resolved.
        // https://github.com/matrix-org/matrix-js-sdk/issues/496
-        client.sendMessage(roomId, "m2");
+        client.sendMessage(roomId, {
+            "msgtype": "m.text",
+            "body": "m2",
+        });

        // both events should be in the timeline at this point
        const tl = room.getLiveTimeline().getEvents();
@@ -72,7 +78,7 @@ describe("MatrixClient retrying", function() {
        expect(ev2.status).toEqual(EventStatus.SENDING);

        // the first message should get sent, and the second should get queued
-        httpBackend.when("PUT", "/send/m.room.message/").check(function(rq) {
+        httpBackend.when("PUT", "/send/m.room.message/").check(function() {
            // ev2 should now have been queued
            expect(ev2.status).toEqual(EventStatus.QUEUED);

@@ -88,8 +94,8 @@ describe("MatrixClient retrying", function() {
        }).respond(400); // fail the first message

        // wait for the localecho of ev1 to be updated
-        const p3 = new Promise((resolve, reject) => {
-            room.on("Room.localEchoUpdated", (ev0) => {
+        const p3 = new Promise<void>((resolve, reject) => {
+            room.on(RoomEvent.LocalEchoUpdated, (ev0) => {
                if (ev0 === ev1) {
                    resolve();
                }
@@ -96,7 +96,7 @@ describe("MatrixClient room timelines", function() {
        });
    }

-    beforeEach(function() {
+    beforeEach(async function() {
        // these tests should work with or without timelineSupport
        const testClient = new TestClient(
            userId,
@@ -109,6 +109,7 @@ describe("MatrixClient room timelines", function() {
        client = testClient.client;

        setNextSyncData();
+        httpBackend.when("GET", "/capabilities").respond(200, { capabilities: {} });
        httpBackend.when("GET", "/pushrules").respond(200, {});
        httpBackend.when("POST", "/filter").respond(200, { filter_id: "fid" });
        httpBackend.when("GET", "/sync").respond(200, SYNC_DATA);
@@ -116,9 +117,10 @@ describe("MatrixClient room timelines", function() {
            return NEXT_SYNC_DATA;
        });
        client.startClient();
-        return httpBackend.flush("/pushrules").then(function() {
-            return httpBackend.flush("/filter");
-        });
+
+        await httpBackend.flush("/capabilities");
+        await httpBackend.flush("/pushrules");
+        await httpBackend.flush("/filter");
    });

    afterEach(function() {
@@ -19,6 +19,7 @@ describe("MatrixClient syncing", function() {
        const testClient = new TestClient(selfUserId, "DEVICE", selfAccessToken);
        httpBackend = testClient.httpBackend;
        client = testClient.client;
+        httpBackend.when("GET", "/capabilities").respond(200, { capabilities: {} });
        httpBackend.when("GET", "/pushrules").respond(200, {});
        httpBackend.when("POST", "/filter").respond(200, { filter_id: "a filter id" });
    });
@@ -16,6 +16,7 @@ limitations under the License.
 */

 import anotherjson from "another-json";
+
 import * as testUtils from "../test-utils";
 import { TestClient } from "../TestClient";
 import { logger } from "../../src/logger";
@@ -85,6 +85,7 @@ export function mkEvent(opts) {
        room_id: opts.room,
        sender: opts.sender || opts.user, // opts.user for backwards-compat
        content: opts.content,
+        unsigned: opts.unsigned,
        event_id: "$" + Math.random() + "-" + Math.random(),
    };
    if (opts.skey !== undefined) {
@@ -341,8 +342,15 @@ HttpResponse.SYNC_RESPONSE = {
    data: HttpResponse.SYNC_DATA,
 };

+HttpResponse.CAPABILITIES_RESPONSE = {
+    method: "GET",
+    path: "/capabilities",
+    data: { capabilities: {} },
+};
+
 HttpResponse.defaultResponses = function(userId) {
    return [
+        HttpResponse.CAPABILITIES_RESPONSE,
        HttpResponse.PUSH_RULES_RESPONSE,
        HttpResponse.filterResponse(userId),
        HttpResponse.SYNC_RESPONSE,
@@ -350,19 +358,13 @@ HttpResponse.defaultResponses = function(userId) {
 };

 export function setHttpResponses(
-    client, responses, acceptKeepalives, ignoreUnhandledSyncs,
+    httpBackend, responses,
 ) {
-    const httpResponseObj = new HttpResponse(
-        responses, acceptKeepalives, ignoreUnhandledSyncs,
-    );
-
-    const httpReq = httpResponseObj.request.bind(httpResponseObj);
-    client.http = [
-        "authedRequest", "authedRequestWithPrefix", "getContentUri",
-        "request", "requestWithPrefix", "uploadContent",
-    ].reduce((r, k) => {r[k] = jest.fn(); return r;}, {});
-    client.http.authedRequest.mockImplementation(httpReq);
-    client.http.authedRequestWithPrefix.mockImplementation(httpReq);
-    client.http.requestWithPrefix.mockImplementation(httpReq);
-    client.http.request.mockImplementation(httpReq);
+    responses.forEach(response => {
+        httpBackend
+            .when(response.method, response.path)
+            .respond(200, response.data);
+    });
 }
+
+export const emitPromise = (e, k) => new Promise(r => e.once(k, r));
@@ -14,7 +14,9 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

+// eslint-disable-next-line no-restricted-imports
 import { EventEmitter } from "events";
+
 import { ReEmitter } from "../../src/ReEmitter";

 const EVENTNAME = "UnknownEntry";
@@ -16,6 +16,7 @@ limitations under the License.
 */

 import MockHttpBackend from "matrix-mock-request";
+
 import * as sdk from "../../src";
 import { AutoDiscovery } from "../../src/autodiscovery";

@@ -1,4 +1,7 @@
 import '../olm-loader';
+// eslint-disable-next-line no-restricted-imports
+import { EventEmitter } from "events";
+
 import { Crypto } from "../../src/crypto";
 import { WebStorageSessionStore } from "../../src/store/session/webstorage";
 import { MemoryCryptoStore } from "../../src/crypto/store/memory-crypto-store";
@@ -8,7 +11,6 @@ import { MatrixEvent } from "../../src/models/event";
 import { Room } from "../../src/models/room";
 import * as olmlib from "../../src/crypto/olmlib";
 import { sleep } from "../../src/utils";
-import { EventEmitter } from "events";
 import { CRYPTO_ENABLED } from "../../src/client";
 import { DeviceInfo } from "../../src/crypto/deviceinfo";

@@ -256,97 +256,145 @@ describe("MegolmDecryption", function() {
            });
        });

-        it("re-uses sessions for sequential messages", async function() {
-            mockCrypto.backupManager = {
-                backupGroupSession: () => {},
-            };
-            const mockStorage = new MockStorageApi();
-            const cryptoStore = new MemoryCryptoStore(mockStorage);
+        describe("session reuse and key reshares", () => {
+            let megolmEncryption;
+            let aliceDeviceInfo;
+            let mockRoom;
+            let olmDevice;

-            const olmDevice = new OlmDevice(cryptoStore);
-            olmDevice.verifySignature = jest.fn();
-            await olmDevice.init();
+            beforeEach(async () => {
+                mockCrypto.backupManager = {
+                    backupGroupSession: () => {},
+                };
+                const mockStorage = new MockStorageApi();
+                const cryptoStore = new MemoryCryptoStore(mockStorage);

-            mockBaseApis.claimOneTimeKeys = jest.fn().mockReturnValue(Promise.resolve({
-                one_time_keys: {
-                    '@alice:home.server': {
-                        aliceDevice: {
-                            'signed_curve25519:flooble': {
-                                key: 'YmJiYmJiYmJiYmJiYmJiYmJiYmJiYmJiYmJiYmJiYmI',
-                                signatures: {
-                                    '@alice:home.server': {
-                                        'ed25519:aliceDevice': 'totally valid',
+                olmDevice = new OlmDevice(cryptoStore);
+                olmDevice.verifySignature = jest.fn();
+                await olmDevice.init();
+
+                mockBaseApis.claimOneTimeKeys = jest.fn().mockReturnValue(Promise.resolve({
+                    one_time_keys: {
+                        '@alice:home.server': {
+                            aliceDevice: {
+                                'signed_curve25519:flooble': {
+                                    key: 'YmJiYmJiYmJiYmJiYmJiYmJiYmJiYmJiYmJiYmJiYmI',
+                                    signatures: {
+                                        '@alice:home.server': {
+                                            'ed25519:aliceDevice': 'totally valid',
+                                        },
                                    },
                                },
                            },
                        },
                    },
-                },
-            }));
-            mockBaseApis.sendToDevice = jest.fn().mockResolvedValue(undefined);
+                }));
+                mockBaseApis.sendToDevice = jest.fn().mockResolvedValue(undefined);

-            mockCrypto.downloadKeys.mockReturnValue(Promise.resolve({
-                '@alice:home.server': {
-                    aliceDevice: {
-                        deviceId: 'aliceDevice',
-                        isBlocked: jest.fn().mockReturnValue(false),
-                        isUnverified: jest.fn().mockReturnValue(false),
-                        getIdentityKey: jest.fn().mockReturnValue(
-                            'YWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWE',
-                        ),
-                        getFingerprint: jest.fn().mockReturnValue(''),
+                aliceDeviceInfo = {
+                    deviceId: 'aliceDevice',
+                    isBlocked: jest.fn().mockReturnValue(false),
+                    isUnverified: jest.fn().mockReturnValue(false),
+                    getIdentityKey: jest.fn().mockReturnValue(
+                        'YWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWE',
+                    ),
+                    getFingerprint: jest.fn().mockReturnValue(''),
+                };
+
+                mockCrypto.downloadKeys.mockReturnValue(Promise.resolve({
+                    '@alice:home.server': {
+                        aliceDevice: aliceDeviceInfo,
                    },
-                },
-            }));
+                }));

-            mockCrypto.checkDeviceTrust.mockReturnValue({
-                isVerified: () => false,
+                mockCrypto.checkDeviceTrust.mockReturnValue({
+                    isVerified: () => false,
+                });
+
+                megolmEncryption = new MegolmEncryption({
+                    userId: '@user:id',
+                    crypto: mockCrypto,
+                    olmDevice: olmDevice,
+                    baseApis: mockBaseApis,
+                    roomId: ROOM_ID,
+                    config: {
+                        rotation_period_ms: 9999999999999,
+                    },
+                });
+                mockRoom = {
+                    getEncryptionTargetMembers: jest.fn().mockReturnValue(
+                        [{ userId: "@alice:home.server" }],
+                    ),
+                    getBlacklistUnverifiedDevices: jest.fn().mockReturnValue(false),
+                };
            });

-            const megolmEncryption = new MegolmEncryption({
-                userId: '@user:id',
-                crypto: mockCrypto,
-                olmDevice: olmDevice,
-                baseApis: mockBaseApis,
-                roomId: ROOM_ID,
-                config: {
-                    rotation_period_ms: 9999999999999,
-                },
-            });
-            const mockRoom = {
-                getEncryptionTargetMembers: jest.fn().mockReturnValue(
-                    [{ userId: "@alice:home.server" }],
-                ),
-                getBlacklistUnverifiedDevices: jest.fn().mockReturnValue(false),
-            };
-            const ct1 = await megolmEncryption.encryptMessage(mockRoom, "a.fake.type", {
-                body: "Some text",
-            });
-            expect(mockRoom.getEncryptionTargetMembers).toHaveBeenCalled();
+            it("re-uses sessions for sequential messages", async function() {
+                const ct1 = await megolmEncryption.encryptMessage(mockRoom, "a.fake.type", {
+                    body: "Some text",
+                });
+                expect(mockRoom.getEncryptionTargetMembers).toHaveBeenCalled();

-            // this should have claimed a key for alice as it's starting a new session
-            expect(mockBaseApis.claimOneTimeKeys).toHaveBeenCalledWith(
-                [['@alice:home.server', 'aliceDevice']], 'signed_curve25519', 2000,
-            );
-            expect(mockCrypto.downloadKeys).toHaveBeenCalledWith(
-                ['@alice:home.server'], false,
-            );
-            expect(mockBaseApis.sendToDevice).toHaveBeenCalled();
-            expect(mockBaseApis.claimOneTimeKeys).toHaveBeenCalledWith(
-                [['@alice:home.server', 'aliceDevice']], 'signed_curve25519', 2000,
-            );
+                // this should have claimed a key for alice as it's starting a new session
+                expect(mockBaseApis.claimOneTimeKeys).toHaveBeenCalledWith(
+                    [['@alice:home.server', 'aliceDevice']], 'signed_curve25519', 2000,
+                );
+                expect(mockCrypto.downloadKeys).toHaveBeenCalledWith(
+                    ['@alice:home.server'], false,
+                );
+                expect(mockBaseApis.sendToDevice).toHaveBeenCalled();
+                expect(mockBaseApis.claimOneTimeKeys).toHaveBeenCalledWith(
+                    [['@alice:home.server', 'aliceDevice']], 'signed_curve25519', 2000,
+                );

-            mockBaseApis.claimOneTimeKeys.mockReset();
+                mockBaseApis.claimOneTimeKeys.mockReset();

-            const ct2 = await megolmEncryption.encryptMessage(mockRoom, "a.fake.type", {
-                body: "Some more text",
+                const ct2 = await megolmEncryption.encryptMessage(mockRoom, "a.fake.type", {
+                    body: "Some more text",
+                });
+
+                // this should *not* have claimed a key as it should be using the same session
+                expect(mockBaseApis.claimOneTimeKeys).not.toHaveBeenCalled();
+
+                // likewise they should show the same session ID
+                expect(ct2.session_id).toEqual(ct1.session_id);
            });

-            // this should *not* have claimed a key as it should be using the same session
-            expect(mockBaseApis.claimOneTimeKeys).not.toHaveBeenCalled();
+            it("re-shares keys to devices it's already sent to", async function() {
+                const ct1 = await megolmEncryption.encryptMessage(mockRoom, "a.fake.type", {
+                    body: "Some text",
+                });

-            // likewise they should show the same session ID
-            expect(ct2.session_id).toEqual(ct1.session_id);
+                mockBaseApis.sendToDevice.mockClear();
+                await megolmEncryption.reshareKeyWithDevice(
+                    olmDevice.deviceCurve25519Key,
+                    ct1.session_id,
+                    '@alice:home.server',
+                    aliceDeviceInfo,
+                );
+
+                expect(mockBaseApis.sendToDevice).toHaveBeenCalled();
+            });
+
+            it("does not re-share keys to devices whose keys have changed", async function() {
+                const ct1 = await megolmEncryption.encryptMessage(mockRoom, "a.fake.type", {
+                    body: "Some text",
+                });
+
+                aliceDeviceInfo.getIdentityKey = jest.fn().mockReturnValue(
+                    'YWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWI',
+                );
+
+                mockBaseApis.sendToDevice.mockClear();
+                await megolmEncryption.reshareKeyWithDevice(
+                    olmDevice.deviceCurve25519Key,
+                    ct1.session_id,
+                    '@alice:home.server',
+                    aliceDeviceInfo,
+                );
+
+                expect(mockBaseApis.sendToDevice).not.toHaveBeenCalled();
+            });
        });
    });

@@ -246,7 +246,7 @@ describe("OlmDevice", function() {

            // After a single tick through the first task, it should have
            // claimed ownership of all devices to avoid deadlocking others.
-            expect(Object.keys(aliceOlmDevice._sessionsInProgress).length).toBe(2);
+            expect(Object.keys(aliceOlmDevice.sessionsInProgress).length).toBe(2);

            const task2 = alwaysSucceed(olmlib.ensureOlmSessionsForDevices(
                aliceOlmDevice, baseApis, devicesByUserBA,
@@ -254,7 +254,7 @@ describe("OlmDevice", function() {

            // The second task should not have changed the ownership count, as
            // it's waiting on the first task.
-            expect(Object.keys(aliceOlmDevice._sessionsInProgress).length).toBe(2);
+            expect(Object.keys(aliceOlmDevice.sessionsInProgress).length).toBe(2);

            // Track the tasks, but don't await them yet.
            const promises = Promise.all([
@@ -288,7 +288,7 @@ describe("MegolmBackup", function() {
                                        ed25519: "SENDER_ED25519",
                                    },
                                    room_id: ROOM_ID,
-                                    session: ibGroupSession.pickle(olmDevice._pickleKey),
+                                    session: ibGroupSession.pickle(olmDevice.pickleKey),
                                },
                                txn);
                        });
@@ -369,7 +369,7 @@ describe("MegolmBackup", function() {
                                        ed25519: "SENDER_ED25519",
                                    },
                                    room_id: ROOM_ID,
-                                    session: ibGroupSession.pickle(olmDevice._pickleKey),
+                                    session: ibGroupSession.pickle(olmDevice.pickleKey),
                                },
                                txn);
                        });
@@ -546,7 +546,7 @@ describe("MegolmBackup", function() {
                                        ed25519: "SENDER_ED25519",
                                    },
                                    room_id: ROOM_ID,
-                                    session: ibGroupSession.pickle(olmDevice._pickleKey),
+                                    session: ibGroupSession.pickle(olmDevice.pickleKey),
                                },
                                txn);
                        });
@@ -17,6 +17,7 @@ limitations under the License.

 import '../../olm-loader';
 import anotherjson from 'another-json';
+
 import * as olmlib from "../../../src/crypto/olmlib";
 import { TestClient } from '../../TestClient';
 import { HttpResponse, setHttpResponses } from '../../test-utils';
@@ -39,13 +40,14 @@ async function makeTestClient(userInfo, options, keys) {
    options.cryptoCallbacks = Object.assign(
        {}, { getCrossSigningKey, saveCrossSigningKeys }, options.cryptoCallbacks || {},
    );
-    const client = (new TestClient(
+    const testClient = new TestClient(
        userInfo.userId, userInfo.deviceId, undefined, undefined, options,
-    )).client;
+    );
+    const client = testClient.client;

    await client.initCrypto();

-    return client;
+    return { client, httpBackend: testClient.httpBackend };
 }

 describe("Cross Signing", function() {
@@ -59,7 +61,7 @@ describe("Cross Signing", function() {
    });

    it("should sign the master key with the device key", async function() {
-        const alice = await makeTestClient(
+        const { client: alice } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
        );
        alice.uploadDeviceSigningKeys = jest.fn(async (auth, keys) => {
@@ -79,7 +81,7 @@ describe("Cross Signing", function() {
    });

    it("should abort bootstrap if device signing auth fails", async function() {
-        const alice = await makeTestClient(
+        const { client: alice } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
        );
        alice.uploadDeviceSigningKeys = async (auth, keys) => {
@@ -130,7 +132,7 @@ describe("Cross Signing", function() {
    });

    it("should upload a signature when a user is verified", async function() {
-        const alice = await makeTestClient(
+        const { client: alice } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
        );
        alice.uploadDeviceSigningKeys = async () => {};
@@ -160,7 +162,7 @@ describe("Cross Signing", function() {
        await promise;
    });

-    it("should get cross-signing keys from sync", async function() {
+    it.skip("should get cross-signing keys from sync", async function() {
        const masterKey = new Uint8Array([
            0xda, 0x5a, 0x27, 0x60, 0xe3, 0x3a, 0xc5, 0x82,
            0x9d, 0x12, 0xc3, 0xbe, 0xe8, 0xaa, 0xc2, 0xef,
@@ -174,7 +176,7 @@ describe("Cross Signing", function() {
            0x34, 0xf2, 0x4b, 0x64, 0x9b, 0x52, 0xf8, 0x5f,
        ]);

-        const alice = await makeTestClient(
+        const { client: alice, httpBackend } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
            {
                cryptoCallbacks: {
@@ -235,6 +237,7 @@ describe("Cross Signing", function() {

        // feed sync result that includes master key, ssk, device key
        const responses = [
+            HttpResponse.CAPABILITIES_RESPONSE,
            HttpResponse.PUSH_RULES_RESPONSE,
            {
                method: "POST",
@@ -310,9 +313,10 @@ describe("Cross Signing", function() {
                },
            },
        ];
-        setHttpResponses(alice, responses, true, true);
+        setHttpResponses(httpBackend, responses);

-        await alice.startClient();
+        alice.startClient();
+        httpBackend.flushAllExpected();

        // once ssk is confirmed, device key should be trusted
        await keyChangePromise;
@@ -331,7 +335,7 @@ describe("Cross Signing", function() {
    });

    it("should use trust chain to determine device verification", async function() {
-        const alice = await makeTestClient(
+        const { client: alice } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
        );
        alice.uploadDeviceSigningKeys = async () => {};
@@ -414,9 +418,9 @@ describe("Cross Signing", function() {
        expect(bobDeviceTrust2.isTofu()).toBeTruthy();
    });

-    it("should trust signatures received from other devices", async function() {
+    it.skip("should trust signatures received from other devices", async function() {
        const aliceKeys = {};
-        const alice = await makeTestClient(
+        const { client: alice, httpBackend } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
            null,
            aliceKeys,
@@ -490,6 +494,7 @@ describe("Cross Signing", function() {
        // - master key signed by her usk (pretend that it was signed by another
        //   of Alice's devices)
        const responses = [
+            HttpResponse.CAPABILITIES_RESPONSE,
            HttpResponse.PUSH_RULES_RESPONSE,
            {
                method: "POST",
@@ -560,10 +565,10 @@ describe("Cross Signing", function() {
                },
            },
        ];
-        setHttpResponses(alice, responses);
-
-        await alice.startClient();
+        setHttpResponses(httpBackend, responses);

+        alice.startClient();
+        httpBackend.flushAllExpected();
        await keyChangePromise;

        // Bob's device key should be trusted
@@ -578,7 +583,7 @@ describe("Cross Signing", function() {
    });

    it("should dis-trust an unsigned device", async function() {
-        const alice = await makeTestClient(
+        const { client: alice } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
        );
        alice.uploadDeviceSigningKeys = async () => {};
@@ -647,7 +652,7 @@ describe("Cross Signing", function() {
    });

    it("should dis-trust a user when their ssk changes", async function() {
-        const alice = await makeTestClient(
+        const { client: alice } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
        );
        alice.uploadDeviceSigningKeys = async () => {};
@@ -785,7 +790,7 @@ describe("Cross Signing", function() {
    it("should offer to upgrade device verifications to cross-signing", async function() {
        let upgradeResolveFunc;

-        const alice = await makeTestClient(
+        const { client: alice } = await makeTestClient(
            { userId: "@alice:example.com", deviceId: "Osborne2" },
            {
                cryptoCallbacks: {
@@ -797,7 +802,7 @@ describe("Cross Signing", function() {
                },
            },
        );
-        const bob = await makeTestClient(
+        const { client: bob } = await makeTestClient(
            { userId: "@bob:example.com", deviceId: "Dynabook" },
        );

@@ -26,7 +26,7 @@ export async function resetCrossSigningKeys(client, {
        crypto.crossSigningInfo.keys = oldKeys;
        throw e;
    }
-    crypto.baseApis.emit("crossSigning.keysChanged", {});
+    crypto.emit("crossSigning.keysChanged", {});
    await crypto.afterCrossSigningLocalKeyChange();
 }

@@ -18,11 +18,11 @@ import {
    IndexedDBCryptoStore,
 } from '../../../src/crypto/store/indexeddb-crypto-store';
 import { MemoryCryptoStore } from '../../../src/crypto/store/memory-crypto-store';
+import { RoomKeyRequestState } from '../../../src/crypto/OutgoingRoomKeyRequestManager';
+
 import 'fake-indexeddb/auto';
 import 'jest-localstorage-mock';

-import { RoomKeyRequestState } from '../../../src/crypto/OutgoingRoomKeyRequestManager';
-
 const requests = [
    {
        requestId: "A",
@@ -23,7 +23,6 @@ import { makeTestClients } from './verification/util';
 import { encryptAES } from "../../../src/crypto/aes";
 import { resetCrossSigningKeys, createSecretStorageKey } from "./crypto-utils";
 import { logger } from '../../../src/logger';
-
 import * as utils from "../../../src/utils";

 try {
@@ -14,8 +14,8 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 import { InRoomChannel } from "../../../../src/crypto/verification/request/InRoomChannel";
-    "../../../../src/crypto/verification/request/ToDeviceChannel";
 import { MatrixEvent } from "../../../../src/models/event";
+    "../../../../src/crypto/verification/request/ToDeviceChannel";

 describe("InRoomChannel tests", function() {
    const ALICE = "@alice:hs.tld";
@@ -69,7 +69,7 @@ describe("verification request integration tests with crypto layer", function()
            bobVerifier.verify();

            // XXX: Private function access (but it's a test, so we're okay)
-            bobVerifier._endTimer();
+            bobVerifier.endTimer();
        });
        const aliceRequest = await alice.client.requestVerification("@bob:example.com");
        await aliceRequest.waitFor(r => r.started);
@@ -77,6 +77,6 @@ describe("verification request integration tests with crypto layer", function()
        expect(aliceVerifier).toBeInstanceOf(SAS);

        // XXX: Private function access (but it's a test, so we're okay)
-        aliceVerifier._endTimer();
+        aliceVerifier.endTimer();
    });
 });
@@ -14,10 +14,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-import { VerificationBase } from '../../../../src/crypto/verification/Base';
 import { CrossSigningInfo } from '../../../../src/crypto/CrossSigning';
 import { encodeBase64 } from "../../../../src/crypto/olmlib";
 import { setupWebcrypto, teardownWebcrypto } from './util';
+import { VerificationBase } from '../../../../src/crypto/verification/Base';

 jest.useFakeTimers();

@@ -93,7 +93,7 @@ describe("self-verifications", () => {
            undefined, // startEvent
            request,
        );
-        verification._resolve = () => undefined;
+        verification.resolve = () => undefined;

        const result = await verification.done();

@@ -15,9 +15,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

+import nodeCrypto from "crypto";
+
 import { TestClient } from '../../../TestClient';
 import { MatrixEvent } from "../../../../src/models/event";
-import nodeCrypto from "crypto";
 import { logger } from '../../../../src/logger';

 export async function makeTestClients(userInfos, options) {
@@ -1,34 +0,0 @@
-import { FilterComponent } from "../../src/filter-component";
-import { mkEvent } from '../test-utils';
-
-describe("Filter Component", function() {
-    describe("types", function() {
-        it("should filter out events with other types", function() {
-            const filter = new FilterComponent({ types: ['m.room.message'] });
-            const event = mkEvent({
-                type: 'm.room.member',
-                content: { },
-                room: 'roomId',
-                event: true,
-            });
-
-            const checkResult = filter.check(event);
-
-            expect(checkResult).toBe(false);
-        });
-
-        it("should validate events with the same type", function() {
-            const filter = new FilterComponent({ types: ['m.room.message'] });
-            const event = mkEvent({
-                type: 'm.room.message',
-                content: { },
-                room: 'roomId',
-                event: true,
-            });
-
-            const checkResult = filter.check(event);
-
-            expect(checkResult).toBe(true);
-        });
-    });
-});
@@ -0,0 +1,132 @@
+import {
+    RelationType,
+    UNSTABLE_FILTER_RELATED_BY_REL_TYPES,
+    UNSTABLE_FILTER_RELATED_BY_SENDERS,
+} from "../../src";
+import { FilterComponent } from "../../src/filter-component";
+import { mkEvent } from '../test-utils';
+
+describe("Filter Component", function() {
+    describe("types", function() {
+        it("should filter out events with other types", function() {
+            const filter = new FilterComponent({ types: ['m.room.message'] });
+            const event = mkEvent({
+                type: 'm.room.member',
+                content: { },
+                room: 'roomId',
+                event: true,
+            });
+
+            const checkResult = filter.check(event);
+
+            expect(checkResult).toBe(false);
+        });
+
+        it("should validate events with the same type", function() {
+            const filter = new FilterComponent({ types: ['m.room.message'] });
+            const event = mkEvent({
+                type: 'm.room.message',
+                content: { },
+                room: 'roomId',
+                event: true,
+            });
+
+            const checkResult = filter.check(event);
+
+            expect(checkResult).toBe(true);
+        });
+
+        it("should filter out events by relation participation", function() {
+            const currentUserId = '@me:server.org';
+            const filter = new FilterComponent({
+                [UNSTABLE_FILTER_RELATED_BY_SENDERS.name]: [currentUserId],
+            }, currentUserId);
+
+            const threadRootNotParticipated = mkEvent({
+                type: 'm.room.message',
+                content: {},
+                room: 'roomId',
+                user: '@someone-else:server.org',
+                event: true,
+                unsigned: {
+                    "m.relations": {
+                        [RelationType.Thread]: {
+                            count: 2,
+                            current_user_participated: false,
+                        },
+                    },
+                },
+            });
+
+            expect(filter.check(threadRootNotParticipated)).toBe(false);
+        });
+
+        it("should keep events by relation participation", function() {
+            const currentUserId = '@me:server.org';
+            const filter = new FilterComponent({
+                [UNSTABLE_FILTER_RELATED_BY_SENDERS.name]: [currentUserId],
+            }, currentUserId);
+
+            const threadRootParticipated = mkEvent({
+                type: 'm.room.message',
+                content: {},
+                unsigned: {
+                    "m.relations": {
+                        [RelationType.Thread]: {
+                            count: 2,
+                            current_user_participated: true,
+                        },
+                    },
+                },
+                user: '@someone-else:server.org',
+                room: 'roomId',
+                event: true,
+            });
+
+            expect(filter.check(threadRootParticipated)).toBe(true);
+        });
+
+        it("should filter out events by relation type", function() {
+            const filter = new FilterComponent({
+                [UNSTABLE_FILTER_RELATED_BY_REL_TYPES.name]: [RelationType.Thread],
+            });
+
+            const referenceRelationEvent = mkEvent({
+                type: 'm.room.message',
+                content: {},
+                room: 'roomId',
+                event: true,
+                unsigned: {
+                    "m.relations": {
+                        [RelationType.Reference]: {},
+                    },
+                },
+            });
+
+            expect(filter.check(referenceRelationEvent)).toBe(false);
+        });
+
+        it("should keep events by relation type", function() {
+            const filter = new FilterComponent({
+                [UNSTABLE_FILTER_RELATED_BY_REL_TYPES.name]: [RelationType.Thread],
+            });
+
+            const threadRootEvent = mkEvent({
+                type: 'm.room.message',
+                content: {},
+                unsigned: {
+                    "m.relations": {
+                        [RelationType.Thread]: {
+                            count: 2,
+                            current_user_participated: true,
+                        },
+                    },
+                },
+                room: 'roomId',
+                event: true,
+            });
+
+            expect(filter.check(threadRootEvent)).toBe(true);
+        });
+    });
+});
@@ -0,0 +1,56 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { makeLocationContent } from "../../src/content-helpers";
+import {
+    ASSET_NODE_TYPE,
+    LocationAssetType,
+    LOCATION_EVENT_TYPE,
+    TIMESTAMP_NODE_TYPE,
+} from "../../src/@types/location";
+import { TEXT_NODE_TYPE } from "../../src/@types/extensible_events";
+
+describe("Location", function() {
+    it("should create a valid location with defaults", function() {
+        const loc = makeLocationContent("txt", "geo:foo", 134235435);
+        expect(loc.body).toEqual("txt");
+        expect(loc.msgtype).toEqual("m.location");
+        expect(loc.geo_uri).toEqual("geo:foo");
+        expect(LOCATION_EVENT_TYPE.findIn(loc)).toEqual({
+            uri: "geo:foo",
+            description: undefined,
+        });
+        expect(ASSET_NODE_TYPE.findIn(loc)).toEqual({ type: LocationAssetType.Self });
+        expect(TEXT_NODE_TYPE.findIn(loc)).toEqual("txt");
+        expect(TIMESTAMP_NODE_TYPE.findIn(loc)).toEqual(134235435);
+    });
+
+    it("should create a valid location with explicit properties", function() {
+        const loc = makeLocationContent(
+            "txxt", "geo:bar", 134235436, "desc", LocationAssetType.Pin);
+
+        expect(loc.body).toEqual("txxt");
+        expect(loc.msgtype).toEqual("m.location");
+        expect(loc.geo_uri).toEqual("geo:bar");
+        expect(LOCATION_EVENT_TYPE.findIn(loc)).toEqual({
+            uri: "geo:bar",
+            description: "desc",
+        });
+        expect(ASSET_NODE_TYPE.findIn(loc)).toEqual({ type: LocationAssetType.Pin });
+        expect(TEXT_NODE_TYPE.findIn(loc)).toEqual("txxt");
+        expect(TIMESTAMP_NODE_TYPE.findIn(loc)).toEqual(134235436);
+    });
+});
@@ -11,8 +11,9 @@ import {
    UNSTABLE_MSC3089_TREE_SUBTYPE,
 } from "../../src/@types/event";
 import { MEGOLM_ALGORITHM } from "../../src/crypto/olmlib";
-import { MatrixEvent } from "../../src/models/event";
+import { EventStatus, MatrixEvent } from "../../src/models/event";
 import { Preset } from "../../src/@types/partials";
+import * as testUtils from "../test-utils";

 jest.useFakeTimers();

@@ -52,6 +53,12 @@ describe("MatrixClient", function() {
        data: SYNC_DATA,
    };

+    const CAPABILITIES_RESPONSE = {
+        method: "GET",
+        path: "/capabilities",
+        data: { capabilities: {} },
+    };
+
    let httpLookups = [
        // items are objects which look like:
        // {
@@ -84,11 +91,7 @@ describe("MatrixClient", function() {
                    return pendingLookup.promise;
                }
                // >1 pending thing, and they are different, whine.
-                expect(false).toBe(
-                    true, ">1 pending request. You should probably handle them. " +
-                    "PENDING: " + JSON.stringify(pendingLookup) + " JUST GOT: " +
-                    method + " " + path,
-                );
+                expect(false).toBe(true);
            }
            pendingLookup = {
                promise: new Promise(() => {}),
@@ -116,6 +119,7 @@ describe("MatrixClient", function() {
            }

            if (next.error) {
+                // eslint-disable-next-line
                return Promise.reject({
                    errcode: next.error.errcode,
                    httpStatus: next.error.httpStatus,
@@ -126,7 +130,7 @@ describe("MatrixClient", function() {
            }
            return Promise.resolve(next.data);
        }
-        expect(true).toBe(false, "Expected different request. " + logLine);
+        expect(true).toBe(false);
        return new Promise(() => {});
    }

@@ -151,7 +155,7 @@ describe("MatrixClient", function() {
            baseUrl: "https://my.home.server",
            idBaseUrl: identityServerUrl,
            accessToken: "my.access.token",
-            request: function() {}, // NOP
+            request: function() {} as any, // NOP
            store: store,
            scheduler: scheduler,
            userId: userId,
@@ -167,6 +171,7 @@ describe("MatrixClient", function() {
        acceptKeepalives = true;
        pendingLookup = null;
        httpLookups = [];
+        httpLookups.push(CAPABILITIES_RESPONSE);
        httpLookups.push(PUSH_RULES_RESPONSE);
        httpLookups.push(FILTER_RESPONSE);
        httpLookups.push(SYNC_RESPONSE);
@@ -237,6 +242,7 @@ describe("MatrixClient", function() {
    it("should get (unstable) file trees with valid state", async () => {
        const roomId = "!room:example.org";
        const mockRoom = {
+            getMyMembership: () => "join",
            currentState: {
                getStateEvents: (eventType, stateKey) => {
                    if (eventType === EventType.RoomCreate) {
@@ -270,9 +276,33 @@ describe("MatrixClient", function() {
        expect(tree.room).toBe(mockRoom);
    });

+    it("should not get (unstable) file trees if not joined", async () => {
+        const roomId = "!room:example.org";
+        const mockRoom = {
+            getMyMembership: () => "leave", // "not join"
+        };
+        client.getRoom = (getRoomId) => {
+            expect(getRoomId).toEqual(roomId);
+            return mockRoom;
+        };
+        const tree = client.unstableGetFileTreeSpace(roomId);
+        expect(tree).toBeFalsy();
+    });
+
+    it("should not get (unstable) file trees for unknown rooms", async () => {
+        const roomId = "!room:example.org";
+        client.getRoom = (getRoomId) => {
+            expect(getRoomId).toEqual(roomId);
+            return null; // imply unknown
+        };
+        const tree = client.unstableGetFileTreeSpace(roomId);
+        expect(tree).toBeFalsy();
+    });
+
    it("should not get (unstable) file trees with invalid create contents", async () => {
        const roomId = "!room:example.org";
        const mockRoom = {
+            getMyMembership: () => "join",
            currentState: {
                getStateEvents: (eventType, stateKey) => {
                    if (eventType === EventType.RoomCreate) {
@@ -307,6 +337,7 @@ describe("MatrixClient", function() {
    it("should not get (unstable) file trees with invalid purpose/subtype contents", async () => {
        const roomId = "!room:example.org";
        const mockRoom = {
+            getMyMembership: () => "join",
            currentState: {
                getStateEvents: (eventType, stateKey) => {
                    if (eventType === EventType.RoomCreate) {
@@ -338,15 +369,17 @@ describe("MatrixClient", function() {
    });

    it("should not POST /filter if a matching filter already exists", async function() {
-        httpLookups = [];
-        httpLookups.push(PUSH_RULES_RESPONSE);
-        httpLookups.push(SYNC_RESPONSE);
+        httpLookups = [
+            CAPABILITIES_RESPONSE,
+            PUSH_RULES_RESPONSE,
+            SYNC_RESPONSE,
+        ];
        const filterId = "ehfewf";
        store.getFilterIdByName.mockReturnValue(filterId);
-        const filter = new Filter(0, filterId);
+        const filter = new Filter("0", filterId);
        filter.setDefinition({ "room": { "timeline": { "limit": 8 } } });
        store.getFilter.mockReturnValue(filter);
-        const syncPromise = new Promise((resolve, reject) => {
+        const syncPromise = new Promise<void>((resolve, reject) => {
            client.on("sync", function syncListener(state) {
                if (state === "SYNCING") {
                    expect(httpLookups.length).toEqual(0);
@@ -367,7 +400,7 @@ describe("MatrixClient", function() {
        });

        it("should return the same sync state as emitted sync events", async function() {
-            const syncingPromise = new Promise((resolve) => {
+            const syncingPromise = new Promise<void>((resolve) => {
                client.on("sync", function syncListener(state) {
                    expect(state).toEqual(client.getSyncState());
                    if (state === "SYNCING") {
@@ -387,7 +420,7 @@ describe("MatrixClient", function() {
        it("should use an existing filter if id is present in localStorage", function() {
        });
        it("should handle localStorage filterId missing from the server", function(done) {
-            function getFilterName(userId, suffix) {
+            function getFilterName(userId, suffix?: string) {
                // scope this on the user ID because people may login on many accounts
                // and they all need to be stored!
                return "FILTER_SYNC_" + userId + (suffix ? "_" + suffix : "");
@@ -421,12 +454,15 @@ describe("MatrixClient", function() {

    describe("retryImmediately", function() {
        it("should return false if there is no request waiting", async function() {
+            httpLookups = [];
+            httpLookups.push(CAPABILITIES_RESPONSE);
            await client.startClient();
            expect(client.retryImmediately()).toBe(false);
        });

        it("should work on /filter", function(done) {
            httpLookups = [];
+            httpLookups.push(CAPABILITIES_RESPONSE);
            httpLookups.push(PUSH_RULES_RESPONSE);
            httpLookups.push({
                method: "POST", path: FILTER_PATH, error: { errcode: "NOPE_NOPE_NOPE" },
@@ -462,7 +498,7 @@ describe("MatrixClient", function() {
                if (state === "ERROR" && httpLookups.length > 0) {
                    expect(httpLookups.length).toEqual(1);
                    expect(client.retryImmediately()).toBe(
-                        true, "retryImmediately returned false",
+                        true,
                    );
                    jest.advanceTimersByTime(1);
                } else if (state === "RECONNECTING" && httpLookups.length > 0) {
@@ -477,6 +513,7 @@ describe("MatrixClient", function() {

        it("should work on /pushrules", function(done) {
            httpLookups = [];
+            httpLookups.push(CAPABILITIES_RESPONSE);
            httpLookups.push({
                method: "GET", path: "/pushrules/", error: { errcode: "NOPE_NOPE_NOPE" },
            });
@@ -533,6 +570,7 @@ describe("MatrixClient", function() {
        it("should transition null -> ERROR after a failed /filter", function(done) {
            const expectedStates = [];
            httpLookups = [];
+            httpLookups.push(CAPABILITIES_RESPONSE);
            httpLookups.push(PUSH_RULES_RESPONSE);
            httpLookups.push({
                method: "POST", path: FILTER_PATH, error: { errcode: "NOPE_NOPE_NOPE" },
@@ -543,32 +581,33 @@ describe("MatrixClient", function() {
        });

        it("should transition ERROR -> CATCHUP after /sync if prev failed",
-        function(done) {
-            const expectedStates = [];
-            acceptKeepalives = false;
-            httpLookups = [];
-            httpLookups.push(PUSH_RULES_RESPONSE);
-            httpLookups.push(FILTER_RESPONSE);
-            httpLookups.push({
-                method: "GET", path: "/sync", error: { errcode: "NOPE_NOPE_NOPE" },
-            });
-            httpLookups.push({
-                method: "GET", path: KEEP_ALIVE_PATH,
-                error: { errcode: "KEEPALIVE_FAIL" },
-            });
-            httpLookups.push({
-                method: "GET", path: KEEP_ALIVE_PATH, data: {},
-            });
-            httpLookups.push({
-                method: "GET", path: "/sync", data: SYNC_DATA,
-            });
+            function(done) {
+                const expectedStates = [];
+                acceptKeepalives = false;
+                httpLookups = [];
+                httpLookups.push(CAPABILITIES_RESPONSE);
+                httpLookups.push(PUSH_RULES_RESPONSE);
+                httpLookups.push(FILTER_RESPONSE);
+                httpLookups.push({
+                    method: "GET", path: "/sync", error: { errcode: "NOPE_NOPE_NOPE" },
+                });
+                httpLookups.push({
+                    method: "GET", path: KEEP_ALIVE_PATH,
+                    error: { errcode: "KEEPALIVE_FAIL" },
+                });
+                httpLookups.push({
+                    method: "GET", path: KEEP_ALIVE_PATH, data: {},
+                });
+                httpLookups.push({
+                    method: "GET", path: "/sync", data: SYNC_DATA,
+                });

-            expectedStates.push(["RECONNECTING", null]);
-            expectedStates.push(["ERROR", "RECONNECTING"]);
-            expectedStates.push(["CATCHUP", "ERROR"]);
-            client.on("sync", syncChecker(expectedStates, done));
-            client.startClient();
-        });
+                expectedStates.push(["RECONNECTING", null]);
+                expectedStates.push(["ERROR", "RECONNECTING"]);
+                expectedStates.push(["CATCHUP", "ERROR"]);
+                client.on("sync", syncChecker(expectedStates, done));
+                client.startClient();
+            });

        it("should transition PREPARED -> SYNCING after /sync", function(done) {
            const expectedStates = [];
@@ -598,32 +637,32 @@ describe("MatrixClient", function() {
        });

        xit("should transition ERROR -> SYNCING after /sync if prev failed",
-        function(done) {
-            const expectedStates = [];
-            httpLookups.push({
-                method: "GET", path: "/sync", error: { errcode: "NONONONONO" },
-            });
-            httpLookups.push(SYNC_RESPONSE);
+            function(done) {
+                const expectedStates = [];
+                httpLookups.push({
+                    method: "GET", path: "/sync", error: { errcode: "NONONONONO" },
+                });
+                httpLookups.push(SYNC_RESPONSE);

-            expectedStates.push(["PREPARED", null]);
-            expectedStates.push(["SYNCING", "PREPARED"]);
-            expectedStates.push(["ERROR", "SYNCING"]);
-            client.on("sync", syncChecker(expectedStates, done));
-            client.startClient();
-        });
+                expectedStates.push(["PREPARED", null]);
+                expectedStates.push(["SYNCING", "PREPARED"]);
+                expectedStates.push(["ERROR", "SYNCING"]);
+                client.on("sync", syncChecker(expectedStates, done));
+                client.startClient();
+            });

        it("should transition SYNCING -> SYNCING on subsequent /sync successes",
-        function(done) {
-            const expectedStates = [];
-            httpLookups.push(SYNC_RESPONSE);
-            httpLookups.push(SYNC_RESPONSE);
+            function(done) {
+                const expectedStates = [];
+                httpLookups.push(SYNC_RESPONSE);
+                httpLookups.push(SYNC_RESPONSE);

-            expectedStates.push(["PREPARED", null]);
-            expectedStates.push(["SYNCING", "PREPARED"]);
-            expectedStates.push(["SYNCING", "SYNCING"]);
-            client.on("sync", syncChecker(expectedStates, done));
-            client.startClient();
-        });
+                expectedStates.push(["PREPARED", null]);
+                expectedStates.push(["SYNCING", "PREPARED"]);
+                expectedStates.push(["SYNCING", "SYNCING"]);
+                client.on("sync", syncChecker(expectedStates, done));
+                client.startClient();
+            });

        it("should transition ERROR -> ERROR if keepalive keeps failing", function(done) {
            acceptKeepalives = false;
@@ -671,7 +710,8 @@ describe("MatrixClient", function() {

    describe("guest rooms", function() {
        it("should only do /sync calls (without filter/pushrules)", function(done) {
-            httpLookups = []; // no /pushrules or /filter
+            httpLookups = []; // no /pushrules or /filterw
+            httpLookups.push(CAPABILITIES_RESPONSE);
            httpLookups.push({
                method: "GET",
                path: "/sync",
@@ -702,4 +742,242 @@ describe("MatrixClient", function() {
            expect(httpLookups.length).toEqual(0);
        });
    });
+
+    describe("sendEvent", () => {
+        const roomId = "!room:example.org";
+        const body = "This is the body";
+        const content = { body };
+
+        it("overload without threadId works", async () => {
+            const eventId = "$eventId:example.org";
+            const txnId = client.makeTxnId();
+            httpLookups = [{
+                method: "PUT",
+                path: `/rooms/${encodeURIComponent(roomId)}/send/m.room.message/${txnId}`,
+                data: { event_id: eventId },
+                expectBody: content,
+            }];
+
+            await client.sendEvent(roomId, EventType.RoomMessage, content, txnId);
+        });
+
+        it("overload with null threadId works", async () => {
+            const eventId = "$eventId:example.org";
+            const txnId = client.makeTxnId();
+            httpLookups = [{
+                method: "PUT",
+                path: `/rooms/${encodeURIComponent(roomId)}/send/m.room.message/${txnId}`,
+                data: { event_id: eventId },
+                expectBody: content,
+            }];
+
+            await client.sendEvent(roomId, null, EventType.RoomMessage, content, txnId);
+        });
+
+        it("overload with threadId works", async () => {
+            const eventId = "$eventId:example.org";
+            const txnId = client.makeTxnId();
+            httpLookups = [{
+                method: "PUT",
+                path: `/rooms/${encodeURIComponent(roomId)}/send/m.room.message/${txnId}`,
+                data: { event_id: eventId },
+                expectBody: content,
+            }];
+
+            await client.sendEvent(roomId, "$threadId:server", EventType.RoomMessage, content, txnId);
+        });
+    });
+
+    describe("redactEvent", () => {
+        const roomId = "!room:example.org";
+        const mockRoom = {
+            getMyMembership: () => "join",
+            currentState: {
+                getStateEvents: (eventType, stateKey) => {
+                    if (eventType === EventType.RoomEncryption) {
+                        expect(stateKey).toEqual("");
+                        return new MatrixEvent({ content: {} });
+                    } else {
+                        throw new Error("Unexpected event type or state key");
+                    }
+                },
+            },
+            threads: {
+                get: jest.fn(),
+            },
+            addPendingEvent: jest.fn(),
+            updatePendingEvent: jest.fn(),
+        };
+
+        beforeEach(() => {
+            client.getRoom = (getRoomId) => {
+                expect(getRoomId).toEqual(roomId);
+                return mockRoom;
+            };
+        });
+
+        it("overload without threadId works", async () => {
+            const eventId = "$eventId:example.org";
+            const txnId = client.makeTxnId();
+            httpLookups = [{
+                method: "PUT",
+                path: `/rooms/${encodeURIComponent(roomId)}/redact/${encodeURIComponent(eventId)}/${txnId}`,
+                data: { event_id: eventId },
+            }];
+
+            await client.redactEvent(roomId, eventId, txnId);
+        });
+
+        it("overload with null threadId works", async () => {
+            const eventId = "$eventId:example.org";
+            const txnId = client.makeTxnId();
+            httpLookups = [{
+                method: "PUT",
+                path: `/rooms/${encodeURIComponent(roomId)}/redact/${encodeURIComponent(eventId)}/${txnId}`,
+                data: { event_id: eventId },
+            }];
+
+            await client.redactEvent(roomId, null, eventId, txnId);
+        });
+
+        it("overload with threadId works", async () => {
+            const eventId = "$eventId:example.org";
+            const txnId = client.makeTxnId();
+            httpLookups = [{
+                method: "PUT",
+                path: `/rooms/${encodeURIComponent(roomId)}/redact/${encodeURIComponent(eventId)}/${txnId}`,
+                data: { event_id: eventId },
+            }];
+
+            await client.redactEvent(roomId, "$threadId:server", eventId, txnId);
+        });
+
+        it("does not get wrongly encrypted", async () => {
+            const eventId = "$eventId:example.org";
+            const txnId = client.makeTxnId();
+            const reason = "This is the redaction reason";
+            httpLookups = [{
+                method: "PUT",
+                path: `/rooms/${encodeURIComponent(roomId)}/redact/${encodeURIComponent(eventId)}/${txnId}`,
+                expectBody: { reason }, // NOT ENCRYPTED
+                data: { event_id: eventId },
+            }];
+
+            await client.redactEvent(roomId, eventId, txnId, { reason });
+        });
+    });
+
+    describe("cancelPendingEvent", () => {
+        const roomId = "!room:server";
+        const txnId = "m12345";
+
+        const mockRoom = {
+            getMyMembership: () => "join",
+            updatePendingEvent: (event, status) => event.setStatus(status),
+            currentState: {
+                getStateEvents: (eventType, stateKey) => {
+                    if (eventType === EventType.RoomCreate) {
+                        expect(stateKey).toEqual("");
+                        return new MatrixEvent({
+                            content: {
+                                [RoomCreateTypeField]: RoomType.Space,
+                            },
+                        });
+                    } else if (eventType === EventType.RoomEncryption) {
+                        expect(stateKey).toEqual("");
+                        return new MatrixEvent({ content: {} });
+                    } else {
+                        throw new Error("Unexpected event type or state key");
+                    }
+                },
+            },
+        };
+
+        let event;
+        beforeEach(async () => {
+            event = new MatrixEvent({
+                event_id: "~" + roomId + ":" + txnId,
+                user_id: client.credentials.userId,
+                sender: client.credentials.userId,
+                room_id: roomId,
+                origin_server_ts: new Date().getTime(),
+            });
+            event.setTxnId(txnId);
+
+            client.getRoom = (getRoomId) => {
+                expect(getRoomId).toEqual(roomId);
+                return mockRoom;
+            };
+            client.crypto = { // mock crypto
+                encryptEvent: (event, room) => new Promise(() => {}),
+            };
+        });
+
+        function assertCancelled() {
+            expect(event.status).toBe(EventStatus.CANCELLED);
+            expect(client.scheduler.removeEventFromQueue(event)).toBeFalsy();
+            expect(httpLookups.filter(h => h.path.includes("/send/")).length).toBe(0);
+        }
+
+        it("should cancel an event which is queued", () => {
+            event.setStatus(EventStatus.QUEUED);
+            client.scheduler.queueEvent(event);
+            client.cancelPendingEvent(event);
+            assertCancelled();
+        });
+
+        it("should cancel an event which is encrypting", async () => {
+            client.encryptAndSendEvent(null, event);
+            await testUtils.emitPromise(event, "Event.status");
+            client.cancelPendingEvent(event);
+            assertCancelled();
+        });
+
+        it("should cancel an event which is not sent", () => {
+            event.setStatus(EventStatus.NOT_SENT);
+            client.cancelPendingEvent(event);
+            assertCancelled();
+        });
+
+        it("should error when given any other event status", () => {
+            event.setStatus(EventStatus.SENDING);
+            expect(() => client.cancelPendingEvent(event)).toThrow("cannot cancel an event with status sending");
+            expect(event.status).toBe(EventStatus.SENDING);
+        });
+    });
+
+    describe("threads", () => {
+        it("partitions root events to room timeline and thread timeline", () => {
+            const supportsExperimentalThreads = client.supportsExperimentalThreads;
+            client.supportsExperimentalThreads = () => true;
+
+            const rootEvent = new MatrixEvent({
+                "content": {},
+                "origin_server_ts": 1,
+                "room_id": "!room1:matrix.org",
+                "sender": "@alice:matrix.org",
+                "type": "m.room.message",
+                "unsigned": {
+                    "m.relations": {
+                        "io.element.thread": {
+                            "latest_event": {},
+                            "count": 33,
+                            "current_user_participated": false,
+                        },
+                    },
+                },
+                "event_id": "$ev1",
+                "user_id": "@alice:matrix.org",
+            });
+
+            expect(rootEvent.isThreadRoot).toBe(true);
+
+            const [room, threads] = client.partitionThreadedEvents([rootEvent]);
+            expect(room).toHaveLength(1);
+            expect(threads).toHaveLength(1);
+
+            // Restore method
+            client.supportsExperimentalThreads = supportsExperimentalThreads;
+        });
+    });
 });
@@ -14,21 +14,25 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-import { MatrixClient } from "../../../src";
+import { IContent, MatrixClient, MatrixEvent } from "../../../src";
 import { Room } from "../../../src/models/room";
-import { UNSTABLE_MSC3089_BRANCH } from "../../../src/@types/event";
+import { IEncryptedFile, RelationType, UNSTABLE_MSC3089_BRANCH } from "../../../src/@types/event";
 import { EventTimelineSet } from "../../../src/models/event-timeline-set";
 import { EventTimeline } from "../../../src/models/event-timeline";
 import { MSC3089Branch } from "../../../src/models/MSC3089Branch";
+import { MSC3089TreeSpace } from "../../../src/models/MSC3089TreeSpace";

 describe("MSC3089Branch", () => {
    let client: MatrixClient;
    // @ts-ignore - TS doesn't know that this is a type
    let indexEvent: any;
+    let directory: MSC3089TreeSpace;
    let branch: MSC3089Branch;
+    let branch2: MSC3089Branch;

    const branchRoomId = "!room:example.org";
    const fileEventId = "$file";
+    const fileEventId2 = "$second_file";

    const staticTimelineSets = {} as EventTimelineSet;
    const staticRoom = {
@@ -50,7 +54,12 @@ describe("MSC3089Branch", () => {
            getRoomId: () => branchRoomId,
            getStateKey: () => fileEventId,
        });
-        branch = new MSC3089Branch(client, indexEvent);
+        directory = new MSC3089TreeSpace(client, branchRoomId);
+        branch = new MSC3089Branch(client, indexEvent, directory);
+        branch2 = new MSC3089Branch(client, {
+            getRoomId: () => branchRoomId,
+            getStateKey: () => fileEventId2,
+        } as MatrixEvent, directory);
    });

    it('should know the file event ID', () => {
@@ -69,13 +78,15 @@ describe("MSC3089Branch", () => {
    });

    it('should be able to delete the file', async () => {
+        const eventIdOrder = [fileEventId, fileEventId2];
+
        const stateFn = jest.fn()
            .mockImplementation((roomId: string, eventType: string, content: any, stateKey: string) => {
                expect(roomId).toEqual(branchRoomId);
                expect(eventType).toEqual(UNSTABLE_MSC3089_BRANCH.unstable); // test that we're definitely using the unstable value
                expect(content).toMatchObject({});
                expect(content['active']).toBeUndefined();
-                expect(stateKey).toEqual(fileEventId);
+                expect(stateKey).toEqual(eventIdOrder[stateFn.mock.calls.length - 1]);

                return Promise.resolve(); // return value not used
            });
@@ -83,16 +94,19 @@ describe("MSC3089Branch", () => {

        const redactFn = jest.fn().mockImplementation((roomId: string, eventId: string) => {
            expect(roomId).toEqual(branchRoomId);
-            expect(eventId).toEqual(fileEventId);
+            expect(eventId).toEqual(eventIdOrder[stateFn.mock.calls.length - 1]);

            return Promise.resolve(); // return value not used
        });
        client.redactEvent = redactFn;

+        branch.getVersionHistory = () => Promise.resolve([branch, branch2]);
+        branch2.getVersionHistory = () => Promise.resolve([branch2]);
+
        await branch.delete();

-        expect(stateFn).toHaveBeenCalledTimes(1);
-        expect(redactFn).toHaveBeenCalledTimes(1);
+        expect(stateFn).toHaveBeenCalledTimes(2);
+        expect(redactFn).toHaveBeenCalledTimes(2);
    });

    it('should know its name', async () => {
@@ -127,16 +141,71 @@ describe("MSC3089Branch", () => {
        expect(stateFn).toHaveBeenCalledTimes(1);
    });

+    it('should be v1 by default', () => {
+        indexEvent.getContent = () => ({ active: true });
+
+        const res = branch.version;
+
+        expect(res).toEqual(1);
+    });
+
+    it('should be vN when set', () => {
+        indexEvent.getContent = () => ({ active: true, version: 3 });
+
+        const res = branch.version;
+
+        expect(res).toEqual(3);
+    });
+
+    it('should be unlocked by default', async () => {
+        indexEvent.getContent = () => ({ active: true });
+
+        const res = branch.isLocked();
+
+        expect(res).toEqual(false);
+    });
+
+    it('should use lock status from index event', async () => {
+        indexEvent.getContent = () => ({ active: true, locked: true });
+
+        const res = branch.isLocked();
+
+        expect(res).toEqual(true);
+    });
+
+    it('should be able to change its locked status', async () => {
+        const locked = true;
+        indexEvent.getContent = () => ({ active: true, retained: true });
+        const stateFn = jest.fn()
+            .mockImplementation((roomId: string, eventType: string, content: any, stateKey: string) => {
+                expect(roomId).toEqual(branchRoomId);
+                expect(eventType).toEqual(UNSTABLE_MSC3089_BRANCH.unstable); // test that we're definitely using the unstable value
+                expect(content).toMatchObject({
+                    retained: true, // canary for copying state
+                    active: true,
+                    locked: locked,
+                });
+                expect(stateKey).toEqual(fileEventId);
+
+                return Promise.resolve(); // return value not used
+            });
+        client.sendStateEvent = stateFn;
+
+        await branch.setLocked(locked);
+
+        expect(stateFn).toHaveBeenCalledTimes(1);
+    });
+
    it('should be able to return event information', async () => {
        const mxcLatter = "example.org/file";
        const fileContent = { isFile: "not quite", url: "mxc://" + mxcLatter };
-        const eventsArr = [
-            { getId: () => "$not-file", getContent: () => ({}) },
-            { getId: () => fileEventId, getContent: () => ({ file: fileContent }) },
-        ];
-        client.getEventTimeline = () => Promise.resolve({
-            getEvents: () => eventsArr,
-        }) as any as Promise<EventTimeline>; // partial
+        const fileEvent = { getId: () => fileEventId, getOriginalContent: () => ({ file: fileContent }) };
+        staticRoom.getUnfilteredTimelineSet = () => ({
+            findEventById: (eventId) => {
+                expect(eventId).toEqual(fileEventId);
+                return fileEvent;
+            },
+        }) as EventTimelineSet;
        client.mxcUrlToHttp = (mxc: string) => {
            expect(mxc).toEqual("mxc://" + mxcLatter);
            return `https://example.org/_matrix/media/v1/download/${mxcLatter}`;
@@ -151,4 +220,112 @@ describe("MSC3089Branch", () => {
            httpUrl: expect.stringMatching(`.+${mxcLatter.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')}$`),
        });
    });
+
+    it('should be able to return the event object', async () => {
+        const mxcLatter = "example.org/file";
+        const fileContent = { isFile: "not quite", url: "mxc://" + mxcLatter };
+        const fileEvent = { getId: () => fileEventId, getOriginalContent: () => ({ file: fileContent }) };
+        staticRoom.getUnfilteredTimelineSet = () => ({
+            findEventById: (eventId) => {
+                expect(eventId).toEqual(fileEventId);
+                return fileEvent;
+            },
+        }) as EventTimelineSet;
+        client.mxcUrlToHttp = (mxc: string) => {
+            expect(mxc).toEqual("mxc://" + mxcLatter);
+            return `https://example.org/_matrix/media/v1/download/${mxcLatter}`;
+        };
+        client.decryptEventIfNeeded = () => Promise.resolve();
+
+        const res = await branch.getFileEvent();
+        expect(res).toBeDefined();
+        expect(res).toBe(fileEvent);
+    });
+
+    it('should create new versions of itself', async () => {
+        const canaryName = "canary";
+        const canaryContents = "contents go here";
+        const canaryFile = {} as IEncryptedFile;
+        const canaryAddl = { canary: true };
+        indexEvent.getContent = () => ({ active: true, retained: true });
+        const stateKeyOrder = [fileEventId2, fileEventId];
+        const stateFn = jest.fn()
+            .mockImplementation((roomId: string, eventType: string, content: any, stateKey: string) => {
+                expect(roomId).toEqual(branchRoomId);
+                expect(eventType).toEqual(UNSTABLE_MSC3089_BRANCH.unstable); // test that we're definitely using the unstable value
+                expect(stateKey).toEqual(stateKeyOrder[stateFn.mock.calls.length - 1]);
+                if (stateKey === fileEventId) {
+                    expect(content).toMatchObject({
+                        retained: true, // canary for copying state
+                        active: false,
+                    });
+                } else if (stateKey === fileEventId2) {
+                    expect(content).toMatchObject({
+                        active: true,
+                        version: 2,
+                        name: canaryName,
+                    });
+                } else {
+                    throw new Error("Unexpected state key: " + stateKey);
+                }
+
+                return Promise.resolve(); // return value not used
+            });
+        client.sendStateEvent = stateFn;
+
+        const createFn = jest.fn().mockImplementation((
+            name: string,
+            contents: ArrayBuffer,
+            info: Partial<IEncryptedFile>,
+            addl: IContent,
+        ) => {
+            expect(name).toEqual(canaryName);
+            expect(contents).toBe(canaryContents);
+            expect(info).toBe(canaryFile);
+            expect(addl).toMatchObject({
+                ...canaryAddl,
+                "m.new_content": true,
+                "m.relates_to": {
+                    "rel_type": RelationType.Replace,
+                    "event_id": fileEventId,
+                },
+            });
+
+            return Promise.resolve({ event_id: fileEventId2 });
+        });
+        directory.createFile = createFn;
+
+        await branch.createNewVersion(canaryName, canaryContents, canaryFile, canaryAddl);
+
+        expect(stateFn).toHaveBeenCalledTimes(2);
+        expect(createFn).toHaveBeenCalledTimes(1);
+    });
+
+    it('should fetch file history', async () => {
+        branch2.getFileEvent = () => Promise.resolve({
+            replacingEventId: () => undefined,
+            getId: () => fileEventId2,
+        } as MatrixEvent);
+        branch.getFileEvent = () => Promise.resolve({
+            replacingEventId: () => fileEventId2,
+            getId: () => fileEventId,
+        } as MatrixEvent);
+
+        const events = [await branch.getFileEvent(), await branch2.getFileEvent(), {
+            replacingEventId: (): string => null,
+            getId: () => "$unknown",
+        }];
+        staticRoom.getLiveTimeline = () => ({ getEvents: () => events }) as EventTimeline;
+
+        directory.getFile = (evId: string) => {
+            expect(evId).toEqual(fileEventId);
+            return branch;
+        };
+
+        const results = await branch2.getVersionHistory();
+        expect(results).toMatchObject([
+            branch2,
+            branch,
+        ]);
+    });
 });
@@ -24,7 +24,6 @@ import {
    TreePermissions,
 } from "../../../src/models/MSC3089TreeSpace";
 import { DEFAULT_ALPHABET } from "../../../src/utils";
-import { MockBlob } from "../../MockBlob";
 import { MatrixError } from "../../../src/http-api";

 describe("MSC3089TreeSpace", () => {
@@ -227,40 +226,61 @@ describe("MSC3089TreeSpace", () => {
                        [targetUser]: expectedPl,
                    },
                });
+
+                // Store new power levels so the `getPermissions()` test passes
+                makePowerLevels(content);
+
                return Promise.resolve();
            });
        client.sendStateEvent = fn;
        await tree.setPermissions(targetUser, role);
        expect(fn.mock.calls.length).toBe(1);
+
+        const finalPermissions = tree.getPermissions(targetUser);
+        expect(finalPermissions).toEqual(role);
    }

    it('should support setting Viewer permissions', () => {
        return evaluatePowerLevels({
            ...DEFAULT_TREE_POWER_LEVELS_TEMPLATE,
            users_default: 1024,
+            events_default: 1025,
+            events: {
+                [EventType.RoomPowerLevels]: 1026,
+            },
        }, TreePermissions.Viewer, 1024);
    });

    it('should support setting Editor permissions', () => {
        return evaluatePowerLevels({
            ...DEFAULT_TREE_POWER_LEVELS_TEMPLATE,
-            events_default: 1024,
-        }, TreePermissions.Editor, 1024);
+            users_default: 1024,
+            events_default: 1025,
+            events: {
+                [EventType.RoomPowerLevels]: 1026,
+            },
+        }, TreePermissions.Editor, 1025);
    });

    it('should support setting Owner permissions', () => {
        return evaluatePowerLevels({
            ...DEFAULT_TREE_POWER_LEVELS_TEMPLATE,
+            users_default: 1024,
+            events_default: 1025,
            events: {
-                [EventType.RoomPowerLevels]: 1024,
+                [EventType.RoomPowerLevels]: 1026,
            },
-        }, TreePermissions.Owner, 1024);
+        }, TreePermissions.Owner, 1026);
    });

    it('should support demoting permissions', () => {
        return evaluatePowerLevels({
            ...DEFAULT_TREE_POWER_LEVELS_TEMPLATE,
            users_default: 1024,
+            events_default: 1025,
+            events: {
+                [EventType.RoomPowerLevels]: 1026,
+            },
            users: {
                [targetUser]: 2222,
            },
@@ -270,11 +290,15 @@ describe("MSC3089TreeSpace", () => {
    it('should support promoting permissions', () => {
        return evaluatePowerLevels({
            ...DEFAULT_TREE_POWER_LEVELS_TEMPLATE,
-            events_default: 1024,
+            users_default: 1024,
+            events_default: 1025,
+            events: {
+                [EventType.RoomPowerLevels]: 1026,
+            },
            users: {
                [targetUser]: 5,
            },
-        }, TreePermissions.Editor, 1024);
+        }, TreePermissions.Editor, 1025);
    });

    it('should support defaults: Viewer', () => {
@@ -862,12 +886,8 @@ describe("MSC3089TreeSpace", () => {
        const fileName = "My File.txt";
        const fileContents = "This is a test file";

-        // Mock out Blob for the test environment
-        (<any>global).Blob = MockBlob;
-
-        const uploadFn = jest.fn().mockImplementation((contents: Blob, opts: any) => {
-            expect(contents).toBeInstanceOf(Blob);
-            expect(contents.size).toEqual(fileContents.length);
+        const uploadFn = jest.fn().mockImplementation((contents: Buffer, opts: any) => {
+            expect(contents.length).toEqual(fileContents.length);
            expect(opts).toMatchObject({
                includeFilename: false,
                onlyContentUri: true, // because the tests rely on this - we shouldn't really be testing  for this.
@@ -883,6 +903,7 @@ describe("MSC3089TreeSpace", () => {
                body: fileName,
                url: mxc,
                file: fileInfo,
+                metadata: true, // additional content from test
                [UNSTABLE_MSC3089_LEAF.unstable]: {}, // test to ensure we're definitely using unstable
            });

@@ -900,14 +921,78 @@ describe("MSC3089TreeSpace", () => {
                    name: fileName,
                });

-                return Promise.resolve(); // return value not used.
+                return Promise.resolve({ event_id: "wrong" }); // return value shouldn't be used
            });
        client.sendStateEvent = sendStateFn;

-        const buf = Uint8Array.from(Array.from(fileContents).map((_, i) => fileContents.charCodeAt(i)));
+        const buf = Buffer.from(fileContents);

        // We clone the file info just to make sure it doesn't get mutated for the test.
-        await tree.createFile(fileName, buf, Object.assign({}, fileInfo));
+        const result = await tree.createFile(fileName, buf, Object.assign({}, fileInfo), { metadata: true });
+        expect(result).toMatchObject({ event_id: fileEventId });
+
+        expect(uploadFn).toHaveBeenCalledTimes(1);
+        expect(sendMsgFn).toHaveBeenCalledTimes(1);
+        expect(sendStateFn).toHaveBeenCalledTimes(1);
+    });
+
+    it('should upload file versions', async () => {
+        const mxc = "mxc://example.org/file";
+        const fileInfo = {
+            mimetype: "text/plain",
+            // other fields as required by encryption, but ignored here
+        };
+        const fileEventId = "$file";
+        const fileName = "My File.txt";
+        const fileContents = "This is a test file";
+
+        const uploadFn = jest.fn().mockImplementation((contents: Buffer, opts: any) => {
+            expect(contents.length).toEqual(fileContents.length);
+            expect(opts).toMatchObject({
+                includeFilename: false,
+                onlyContentUri: true, // because the tests rely on this - we shouldn't really be testing  for this.
+            });
+            return Promise.resolve(mxc);
+        });
+        client.uploadContent = uploadFn;
+
+        const sendMsgFn = jest.fn().mockImplementation((roomId: string, contents: any) => {
+            expect(roomId).toEqual(tree.roomId);
+            const content = {
+                msgtype: MsgType.File,
+                body: fileName,
+                url: mxc,
+                file: fileInfo,
+            };
+            expect(contents).toMatchObject({
+                ...content,
+                "m.new_content": content,
+                [UNSTABLE_MSC3089_LEAF.unstable]: {}, // test to ensure we're definitely using unstable
+            });
+
+            return Promise.resolve({ event_id: fileEventId }); // eslint-disable-line camelcase
+        });
+        client.sendMessage = sendMsgFn;
+
+        const sendStateFn = jest.fn()
+            .mockImplementation((roomId: string, eventType: string, content: any, stateKey: string) => {
+                expect(roomId).toEqual(tree.roomId);
+                expect(eventType).toEqual(UNSTABLE_MSC3089_BRANCH.unstable); // test to ensure we're definitely using unstable
+                expect(stateKey).toEqual(fileEventId);
+                expect(content).toMatchObject({
+                    active: true,
+                    name: fileName,
+                });
+
+                return Promise.resolve({ event_id: "wrong" }); // return value shouldn't be used
+            });
+        client.sendStateEvent = sendStateFn;
+
+        const buf = Buffer.from(fileContents);
+
+        // We clone the file info just to make sure it doesn't get mutated for the test.
+        const result = await tree.createFile(fileName, buf, Object.assign({}, fileInfo), { "m.new_content": true });
+        expect(result).toMatchObject({ event_id: fileEventId });

        expect(uploadFn).toHaveBeenCalledTimes(1);
        expect(sendMsgFn).toHaveBeenCalledTimes(1);
@@ -933,7 +1018,7 @@ describe("MSC3089TreeSpace", () => {
    it('should return falsy for unknown files', () => {
        const fileEventId = "$file";
        room.currentState = {
-            getStateEvents: (eventType: string, stateKey?: string) => {
+            getStateEvents: (eventType: string, stateKey?: string): MatrixEvent[] | MatrixEvent | null => {
                expect(eventType).toEqual(UNSTABLE_MSC3089_BRANCH.unstable); // test to ensure we're definitely using unstable
                expect(stateKey).toEqual(fileEventId);
                return null;
@@ -960,4 +1045,22 @@ describe("MSC3089TreeSpace", () => {
        expect(files.length).toEqual(1);
        expect(files[0].indexEvent).toBe(firstFile);
    });
+
+    it('should list all files', () => {
+        const firstFile = { getContent: () => ({ active: true }) };
+        const secondFile = { getContent: () => ({ active: false }) }; // deliberately inactive
+        room.currentState = {
+            getStateEvents: (eventType: string, stateKey?: string) => {
+                expect(eventType).toEqual(UNSTABLE_MSC3089_BRANCH.unstable); // test to ensure we're definitely using unstable
+                expect(stateKey).toBeUndefined();
+                return [firstFile, secondFile];
+            },
+        };
+
+        const files = tree.listAllFiles();
+        expect(files).toBeDefined();
+        expect(files.length).toEqual(2);
+        expect(files[0].indexEvent).toBe(firstFile);
+        expect(files[1].indexEvent).toBe(secondFile);
+    });
 });
@@ -302,4 +302,20 @@ describe('NotificationService', function() {
        const actions = pushProcessor.actionsForEvent(testEvent);
        expect(actions.tweaks.highlight).toEqual(false);
    });
+
+    it("a rule with no conditions matches every event.", function() {
+        expect(pushProcessor.ruleMatchesEvent({
+            rule_id: "rule1",
+            actions: [],
+            conditions: [],
+            default: false,
+            enabled: true,
+        }, testEvent)).toBe(true);
+        expect(pushProcessor.ruleMatchesEvent({
+            rule_id: "rule1",
+            actions: [],
+            default: false,
+            enabled: true,
+        }, testEvent)).toBe(true);
+    });
 });
@@ -15,7 +15,7 @@ limitations under the License.
 */

 import { EventTimelineSet } from "../../src/models/event-timeline-set";
-import { MatrixEvent } from "../../src/models/event";
+import { MatrixEvent, MatrixEventEvent } from "../../src/models/event";
 import { Room } from "../../src/models/room";
 import { Relations } from "../../src/models/relations";

@@ -103,7 +103,7 @@ describe("Relations", function() {
        // Add the target event first, then the relation event
        {
            const relationsCreated = new Promise(resolve => {
-                targetEvent.once("Event.relationsCreated", resolve);
+                targetEvent.once(MatrixEventEvent.RelationsCreated, resolve);
            });

            const timelineSet = new EventTimelineSet(room, {
@@ -118,7 +118,7 @@ describe("Relations", function() {
        // Add the relation event first, then the target event
        {
            const relationsCreated = new Promise(resolve => {
-                targetEvent.once("Event.relationsCreated", resolve);
+                targetEvent.once(MatrixEventEvent.RelationsCreated, resolve);
            });

            const timelineSet = new EventTimelineSet(room, {
@@ -120,7 +120,7 @@ describe("RoomState", function() {
        it("should return a single MatrixEvent if a state_key was specified",
        function() {
            const event = state.getStateEvents("m.room.member", userA);
-            expect(event.getContent()).toEqual({
+            expect(event.getContent()).toMatchObject({
                membership: "join",
            });
        });
@@ -26,6 +26,15 @@ describe("utils", function() {
                "foo=bar&baz=beer%40",
            );
        });
+
+        it("should handle boolean and numeric values", function() {
+            const params = {
+                string: "foobar",
+                number: 12345,
+                boolean: false,
+            };
+            expect(utils.encodeParams(params)).toEqual("string=foobar&number=12345&boolean=false");
+        });
    });

    describe("encodeUri", function() {
@@ -111,10 +120,10 @@ describe("utils", function() {

    describe("deepCompare", function() {
        const assert = {
-            isTrue: function(x) {
+            isTrue: function(x: any) {
                expect(x).toBe(true);
            },
-            isFalse: function(x) {
+            isFalse: function(x: any) {
                expect(x).toBe(false);
            },
        };
@@ -176,10 +185,10 @@ describe("utils", function() {
            // no two different function is equal really, they capture their
            // context variables so even if they have same toString(), they
            // won't have same functionality
-            const func = function(x) {
+            const func = function() {
                return true;
            };
-            const func2 = function(x) {
+            const func2 = function() {
                return true;
            };
            assert.isTrue(utils.deepCompare(func, func));
@@ -189,66 +198,6 @@ describe("utils", function() {
        });
    });

-    describe("extend", function() {
-        const SOURCE = { "prop2": 1, "string2": "x", "newprop": "new" };
-
-        it("should extend", function() {
-            const target = {
-                "prop1": 5, "prop2": 7, "string1": "baz", "string2": "foo",
-            };
-            const merged = {
-                "prop1": 5, "prop2": 1, "string1": "baz", "string2": "x",
-                "newprop": "new",
-            };
-            const sourceOrig = JSON.stringify(SOURCE);
-
-            utils.extend(target, SOURCE);
-            expect(JSON.stringify(target)).toEqual(JSON.stringify(merged));
-
-            // check the originial wasn't modified
-            expect(JSON.stringify(SOURCE)).toEqual(sourceOrig);
-        });
-
-        it("should ignore null", function() {
-            const target = {
-                "prop1": 5, "prop2": 7, "string1": "baz", "string2": "foo",
-            };
-            const merged = {
-                "prop1": 5, "prop2": 1, "string1": "baz", "string2": "x",
-                "newprop": "new",
-            };
-            const sourceOrig = JSON.stringify(SOURCE);
-
-            utils.extend(target, null, SOURCE);
-            expect(JSON.stringify(target)).toEqual(JSON.stringify(merged));
-
-            // check the originial wasn't modified
-            expect(JSON.stringify(SOURCE)).toEqual(sourceOrig);
-        });
-
-        it("should handle properties created with defineProperties", function() {
-            const source = Object.defineProperties({}, {
-                "enumerableProp": {
-                    get: function() {
-                        return true;
-                    },
-                    enumerable: true,
-                },
-                "nonenumerableProp": {
-                    get: function() {
-                        return true;
-                    },
-                },
-            });
-
-            // TODO: Fix type
-            const target: any = {};
-            utils.extend(target, source);
-            expect(target.enumerableProp).toBe(true);
-            expect(target.nonenumerableProp).toBe(undefined);
-        });
-    });
-
    describe("chunkPromises", function() {
        it("should execute promises in chunks", async function() {
            let promiseCount = 0;
@@ -273,7 +222,7 @@ describe("utils", function() {
        it('should retry', async () => {
            let count = 0;
            const val = {};
-            const fn = (attempt) => {
+            const fn = (attempt: any) => {
                count++;

                // If this expectation fails then it can appear as a Jest Timeout due to
@@ -480,7 +429,7 @@ describe("utils", function() {
                },
                [72]: "test",
            };
-            const output = [
+            const output: any = [
                ["72", "test"],
                ["a", 42],
                ["b", [
@@ -17,6 +17,7 @@ limitations under the License.
 import { TestClient } from '../../TestClient';
 import { MatrixCall, CallErrorCode, CallEvent } from '../../../src/webrtc/call';
 import { SDPStreamMetadataKey, SDPStreamMetadataPurpose } from '../../../src/webrtc/callEventTypes';
+import { RoomMember } from "../../../src";

 const DUMMY_SDP = (
    "v=0\r\n" +
@@ -81,6 +82,51 @@ class MockRTCPeerConnection {
    }
    close() {}
    getStats() { return []; }
+    addTrack(track: MockMediaStreamTrack) {return new MockRTCRtpSender(track);}
+}
+
+class MockRTCRtpSender {
+    constructor(public track: MockMediaStreamTrack) {}
+
+    replaceTrack(track: MockMediaStreamTrack) {this.track = track;}
+}
+
+class MockMediaStreamTrack {
+    constructor(public readonly id: string, public readonly kind: "audio" | "video", public enabled = true) {}
+
+    stop() {}
+}
+
+class MockMediaStream {
+    constructor(
+        public id: string,
+        private tracks: MockMediaStreamTrack[] = [],
+    ) {}
+
+    getTracks() { return this.tracks; }
+    getAudioTracks() { return this.tracks.filter((track) => track.kind === "audio"); }
+    getVideoTracks() { return this.tracks.filter((track) => track.kind === "video"); }
+    addEventListener() {}
+    removeEventListener() { }
+    addTrack(track: MockMediaStreamTrack) {this.tracks.push(track);}
+    removeTrack(track: MockMediaStreamTrack) {this.tracks.splice(this.tracks.indexOf(track), 1);}
+}
+
+class MockMediaDeviceInfo {
+    constructor(
+        public kind: "audio" | "video",
+    ) {}
+}
+
+class MockMediaHandler {
+    getUserMediaStream(audio: boolean, video: boolean) {
+        const tracks = [];
+        if (audio) tracks.push(new MockMediaStreamTrack("audio_track", "audio"));
+        if (video) tracks.push(new MockMediaStreamTrack("video_track", "video"));
+
+        return new MockMediaStream("mock_stream_from_media_handler", tracks);
+    }
+    stopUserMediaStream() {}
 }

 describe('Call', function() {
@@ -98,13 +144,9 @@ describe('Call', function() {
        global.navigator = {
            mediaDevices: {
                // @ts-ignore Mock
-                getUserMedia: () => {
-                    return {
-                        getTracks: () => [],
-                        getAudioTracks: () => [],
-                        getVideoTracks: () => [],
-                    };
-                },
+                getUserMedia: () => new MockMediaStream("local_stream"),
+                // @ts-ignore Mock
+                enumerateDevices: async () => [new MockMediaDeviceInfo("audio"), new MockMediaDeviceInfo("video")],
            },
        };

@@ -115,7 +157,7 @@ describe('Call', function() {
            RTCSessionDescription: {},
            // @ts-ignore Mock
            RTCIceCandidate: {},
-            getUserMedia: {},
+            getUserMedia: () => new MockMediaStream("local_stream"),
        };
        // @ts-ignore Mock
        global.document = {};
@@ -124,6 +166,8 @@ describe('Call', function() {
        // We just stub out sendEvent: we're not interested in testing the client's
        // event sending code here
        client.client.sendEvent = () => {};
+        client.client.mediaHandler = new MockMediaHandler;
+        client.client.getMediaHandler = () => client.client.mediaHandler;
        client.httpBackend.when("GET", "/voip/turnServer").respond(200, {});
        call = new MatrixCall({
            client: client.client,
@@ -319,7 +363,7 @@ describe('Call', function() {
                        sdp: DUMMY_SDP,
                    },
                    [SDPStreamMetadataKey]: {
-                        "stream_id": {
+                        "remote_stream": {
                            purpose: SDPStreamMetadataPurpose.Usermedia,
                            audio_muted: true,
                            video_muted: false,
@@ -329,8 +373,16 @@ describe('Call', function() {
            },
        });

-        call.pushRemoteFeed({ id: "stream_id", getAudioTracks: () => ["track1"], getVideoTracks: () => ["track1"] });
-        const feed = call.getFeeds().find((feed) => feed.stream.id === "stream_id");
+        call.pushRemoteFeed(
+            new MockMediaStream(
+                "remote_stream",
+                [
+                    new MockMediaStreamTrack("remote_audio_track", "audio"),
+                    new MockMediaStreamTrack("remote_video_track", "video"),
+                ],
+            ),
+        );
+        const feed = call.getFeeds().find((feed) => feed.stream.id === "remote_stream");
        expect(feed?.purpose).toBe(SDPStreamMetadataPurpose.Usermedia);
        expect(feed?.isAudioMuted()).toBeTruthy();
        expect(feed?.isVideoMuted()).not.toBeTruthy();
@@ -342,7 +394,7 @@ describe('Call', function() {
        await callPromise;

        call.getOpponentMember = () => {
-            return { userId: "@bob:bar.uk" };
+            return { userId: "@bob:bar.uk" } as RoomMember;
        };

        await call.onAnswerReceived({
@@ -363,4 +415,94 @@ describe('Call', function() {
        call.setScreensharingEnabled(true);
        expect(call.setScreensharingEnabledWithoutMetadataSupport).toHaveBeenCalled();
    });
+
+    it("should fallback to answering with no video", async () => {
+        await client.httpBackend.flush();
+
+        call.shouldAnswerWithMediaType = (wantedValue: boolean) => wantedValue;
+        client.client.mediaHandler.getUserMediaStream = jest.fn().mockRejectedValue("reject");
+
+        await call.answer(true, true);
+
+        expect(client.client.mediaHandler.getUserMediaStream).toHaveBeenNthCalledWith(1, true, true);
+        expect(client.client.mediaHandler.getUserMediaStream).toHaveBeenNthCalledWith(2, true, false);
+    });
+
+    it("should handle mid-call device changes", async () => {
+        client.client.mediaHandler.getUserMediaStream = jest.fn().mockReturnValue(
+            new MockMediaStream(
+                "stream", [
+                    new MockMediaStreamTrack("audio_track", "audio"),
+                    new MockMediaStreamTrack("video_track", "video"),
+                ],
+            ),
+        );
+
+        const callPromise = call.placeVideoCall();
+        await client.httpBackend.flush();
+        await callPromise;
+
+        await call.onAnswerReceived({
+            getContent: () => {
+                return {
+                    version: 1,
+                    call_id: call.callId,
+                    party_id: 'party_id',
+                    answer: {
+                        sdp: DUMMY_SDP,
+                    },
+                };
+            },
+        });
+
+        await call.updateLocalUsermediaStream(
+            new MockMediaStream(
+                "replacement_stream",
+                [
+                    new MockMediaStreamTrack("new_audio_track", "audio"),
+                    new MockMediaStreamTrack("video_track", "video"),
+                ],
+            ),
+        );
+        expect(call.localUsermediaStream.id).toBe("stream");
+        expect(call.localUsermediaStream.getAudioTracks()[0].id).toBe("new_audio_track");
+        expect(call.localUsermediaStream.getVideoTracks()[0].id).toBe("video_track");
+        expect(call.usermediaSenders.find((sender) => {
+            return sender?.track?.kind === "audio";
+        }).track.id).toBe("new_audio_track");
+        expect(call.usermediaSenders.find((sender) => {
+            return sender?.track?.kind === "video";
+        }).track.id).toBe("video_track");
+    });
+
+    it("should handle upgrade to video call", async () => {
+        const callPromise = call.placeVoiceCall();
+        await client.httpBackend.flush();
+        await callPromise;
+
+        await call.onAnswerReceived({
+            getContent: () => {
+                return {
+                    version: 1,
+                    call_id: call.callId,
+                    party_id: 'party_id',
+                    answer: {
+                        sdp: DUMMY_SDP,
+                    },
+                    [SDPStreamMetadataKey]: {},
+                };
+            },
+        });
+
+        await call.upgradeCall(false, true);
+
+        expect(call.localUsermediaStream.getAudioTracks()[0].id).toBe("audio_track");
+        expect(call.localUsermediaStream.getVideoTracks()[0].id).toBe("video_track");
+        expect(call.usermediaSenders.find((sender) => {
+            return sender?.track?.kind === "audio";
+        }).track.id).toBe("audio_track");
+        expect(call.usermediaSenders.find((sender) => {
+            return sender?.track?.kind === "video";
+        }).track.id).toBe("video_track");
+    });
 });
@@ -90,8 +90,9 @@ export interface ISenderNotificationPermissionCondition
    key: string;
 }

-export type PushRuleCondition = IPushRuleCondition<string>
-    | IEventMatchCondition
+// XXX: custom conditions are possible but always fail, and break the typescript discriminated union so ignore them here
+// IPushRuleCondition<Exclude<string, ConditionKind>> unfortunately does not resolve this at the time of writing.
+export type PushRuleCondition = IEventMatchCondition
    | IContainsDisplayNameCondition
    | IRoomMemberCountCondition
    | ISenderNotificationPermissionCondition;
@@ -146,12 +147,12 @@ export interface IPusher {
    app_display_name: string;
    app_id: string;
    data: {
-        format?: string; // TODO: Types
+        format?: string;
        url?: string; // TODO: Required if kind==http
-        brand?: string; // TODO: For email notifications only?
+        brand?: string; // TODO: For email notifications only? Unspecced field
    };
    device_display_name: string;
-    kind: string; // TODO: Types
+    kind: "http" | string;
    lang: string;
    profile_tag?: string;
    pushkey: string;
@@ -1,5 +1,5 @@
 /*
-Copyright 2021 The Matrix.org Foundation C.I.C.
+Copyright 2022 The Matrix.org Foundation C.I.C.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -14,14 +14,16 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-export class MockBlob {
-    private contents: number[] = [];
+// disable lint because these are wire responses
+/* eslint-disable camelcase */

-    public constructor(private parts: ArrayLike<number>[]) {
-        parts.forEach(p => Array.from(p).forEach(e => this.contents.push(e)));
-    }
-
-    public get size(): number {
-        return this.contents.length;
-    }
+/**
+ * Represents a response to the CSAPI `/refresh` endpoint.
+ */
+export interface IRefreshTokenResponse {
+    access_token: string;
+    expires_in_ms: number;
+    refresh_token: string;
 }
+
+/* eslint-enable camelcase */
@@ -92,6 +92,15 @@ export enum EventType {
 export enum RelationType {
    Annotation = "m.annotation",
    Replace = "m.replace",
+    Reference = "m.reference",
+    /**
+     * Note, "io.element.thread" is hardcoded
+     * Should be replaced with "m.thread" once MSC3440 lands
+     * Can not use `UnstableValue` as TypeScript does not
+     * allow computed values in enums
+     * https://github.com/microsoft/TypeScript/issues/27976
+     */
+    Thread = "io.element.thread",
 }

 export enum MsgType {
@@ -103,6 +112,7 @@ export enum MsgType {
    Audio = "m.audio",
    Location = "m.location",
    Video = "m.video",
+    KeyVerificationRequest = "m.key.verification.request",
 }

 export const RoomCreateTypeField = "type";
@@ -168,6 +178,16 @@ export const UNSTABLE_ELEMENT_FUNCTIONAL_USERS = new UnstableValue(
    "io.element.functional_members",
    "io.element.functional_members");

+/**
+ * A type of message that affects visibility of a message,
+ * as per https://github.com/matrix-org/matrix-doc/pull/3531
+ *
+ * @experimental
+ */
+export const EVENT_VISIBILITY_CHANGE_TYPE = new UnstableValue(
+    "m.visibility",
+    "org.matrix.msc3531.visibility");
+
 export interface IEncryptedFile {
    url: string;
    mimetype?: string;
@@ -14,13 +14,8 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-// TODO: Merge this with sync.js once converted
+// Types for MSC1767: Extensible events in Matrix

-export enum SyncState {
-    Error = "ERROR",
-    Prepared = "PREPARED",
-    Stopped = "STOPPED",
-    Syncing = "SYNCING",
-    Catchup = "CATCHUP",
-    Reconnecting = "RECONNECTING",
-}
+import { UnstableValue } from "../NamespacedValue";
+
+export const TEXT_NODE_TYPE = new UnstableValue("m.text", "org.matrix.msc1767.text");
@@ -33,11 +33,7 @@ declare global {
    }

    interface Window {
-        electron?: Electron;
-    }
-
-    interface Electron {
-        getDesktopCapturerSources(options: GetSourcesOptions): Promise<Array<DesktopCapturerSource>>;
+        webkitAudioContext: typeof AudioContext;
    }

    interface Crypto {
@@ -66,27 +62,6 @@ declare global {
        };
    }

-    interface DesktopCapturerSource {
-        id: string;
-        name: string;
-        thumbnailURL: string;
-    }
-
-    interface GetSourcesOptions {
-        types: Array<string>;
-        thumbnailSize?: {
-            height: number;
-            width: number;
-        };
-        fetchWindowIcons?: boolean;
-    }
-
-    interface HTMLAudioElement {
-        // sinkId & setSinkId are experimental and typescript doesn't know about them
-        sinkId: string;
-        setSinkId(outputId: string);
-    }
-
    interface DummyInterfaceWeShouldntBeUsingThis {}

    interface Navigator {
@@ -107,4 +82,11 @@ declare global {
    interface PromiseConstructor {
        allSettled<T>(promises: Promise<T>[]): Promise<Array<ISettledFulfilled<T> | ISettledRejected>>;
    }
+
+    interface RTCRtpTransceiver {
+        // This has been removed from TS
+        // (https://github.com/microsoft/TypeScript-DOM-lib-generator/issues/1029),
+        // but we still need this for MatrixCall::getRidOfRTXCodecs()
+        setCodecPreferences(codecs: RTCRtpCodecCapability[]): void;
+    }
 }
@@ -0,0 +1,71 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Types for MSC3488 - m.location: Extending events with location data
+
+import { UnstableValue } from "../NamespacedValue";
+import { IContent } from "../models/event";
+import { TEXT_NODE_TYPE } from "./extensible_events";
+
+export const LOCATION_EVENT_TYPE = new UnstableValue(
+    "m.location", "org.matrix.msc3488.location");
+
+export const ASSET_NODE_TYPE = new UnstableValue("m.asset", "org.matrix.msc3488.asset");
+
+export const TIMESTAMP_NODE_TYPE = new UnstableValue("m.ts", "org.matrix.msc3488.ts");
+
+export enum LocationAssetType {
+    Self = "m.self",
+    Pin = "m.pin",
+}
+
+/* From the spec at:
+ * https://github.com/matrix-org/matrix-doc/blob/matthew/location/proposals/3488-location.md
+{
+    "type": "m.room.message",
+    "content": {
+        "body": "Matthew was at geo:51.5008,0.1247;u=35 as of Sat Nov 13 18:50:58 2021",
+        "msgtype": "m.location",
+        "geo_uri": "geo:51.5008,0.1247;u=35",
+        "m.location": {
+            "uri": "geo:51.5008,0.1247;u=35",
+            "description": "Matthew's whereabouts",
+        },
+        "m.asset": {
+            "type": "m.self"
+        },
+        "m.text": "Matthew was at geo:51.5008,0.1247;u=35 as of Sat Nov 13 18:50:58 2021",
+        "m.ts": 1636829458432,
+    }
+}
+*/
+
+/* eslint-disable camelcase */
+export interface ILocationContent extends IContent {
+    body: string;
+    msgtype: string;
+    geo_uri: string;
+    [LOCATION_EVENT_TYPE.name]: {
+        uri: string;
+        description?: string;
+    };
+    [ASSET_NODE_TYPE.name]: {
+        type: LocationAssetType;
+    };
+    [TEXT_NODE_TYPE.name]: string;
+    [TIMESTAMP_NODE_TYPE.name]: number;
+}
+/* eslint-enable camelcase */
@@ -55,12 +55,20 @@ export enum JoinRule {
     * @deprecated Reserved keyword. Should not be used. Not yet implemented.
     */
    Private = "private",
-    Knock = "knock", // MSC2403 - only valid inside experimental room versions at this time.
-    Restricted = "restricted", // MSC3083 - only valid inside experimental room versions at this time.
+    Knock = "knock",
+    Restricted = "restricted",
 }

 export enum RestrictedAllowType {
-    RoomMembership = "m.room_membership", // MSC3083 - only valid inside experimental room versions at this time.
+    RoomMembership = "m.room_membership",
+}
+
+export interface IJoinRuleEventContent {
+    join_rule: JoinRule; // eslint-disable-line camelcase
+    allow?: {
+        type: RestrictedAllowType;
+        room_id: string; // eslint-disable-line camelcase
+    }[];
 }

 export enum GuestAccess {
@@ -75,10 +83,11 @@ export enum HistoryVisibility {
    WorldReadable = "world_readable",
 }

-// XXX move to OlmDevice when converted
-export interface InboundGroupSessionData {
-    room_id: string; // eslint-disable-line camelcase
-    session: string;
-    keysClaimed: Record<string, string>;
-    forwardingCurve25519KeyChain: string[];
+export interface IUsageLimit {
+    // "hs_disabled" is NOT a specced string, but is used in Synapse
+    // This is tracked over at https://github.com/matrix-org/synapse/issues/9237
+    // eslint-disable-next-line camelcase
+    limit_type: "monthly_active_user" | "hs_disabled" | string;
+    // eslint-disable-next-line camelcase
+    admin_contact?: string;
 }
@@ -15,10 +15,11 @@ limitations under the License.
 */

 import { Callback } from "../client";
-import { IContent } from "../models/event";
+import { IContent, IEvent } from "../models/event";
 import { Preset, Visibility } from "./partials";
 import { SearchKey } from "./search";
 import { IRoomEventFilter } from "../filter";
+import { Direction } from "../models/event-timeline";

 // allow camelcase as these are things that go onto the wire
 /* eslint-disable camelcase */
@@ -139,4 +140,19 @@ export interface IBindThreePidBody {
    id_access_token: string;
    sid: string;
 }
+
+export interface IRelationsRequestOpts {
+    from?: string;
+    to?: string;
+    limit?: number;
+    direction?: Direction;
+}
+
+export interface IRelationsResponse {
+    original_event: IEvent;
+    chunk: IEvent[];
+    next_batch?: string;
+    prev_batch?: string;
+}
+
 /* eslint-enable camelcase */
@@ -15,26 +15,23 @@ limitations under the License.
 */

 import { IPublicRoomsChunkRoom } from "../client";
+import { RoomType } from "./event";
+import { IStrippedState } from "../sync-accumulator";

 // Types relating to Rooms of type `m.space` and related APIs

 /* eslint-disable camelcase */
-export interface ISpaceSummaryRoom extends IPublicRoomsChunkRoom {
-    num_refs: number;
-    room_type: string;
-}
-
-export interface ISpaceSummaryEvent {
-    room_id: string;
-    event_id: string;
+export interface IHierarchyRelation extends IStrippedState {
    origin_server_ts: number;
-    type: string;
-    state_key: string;
    content: {
        order?: string;
        suggested?: boolean;
-        auto_join?: boolean;
        via?: string[];
    };
 }
+
+export interface IHierarchyRoom extends IPublicRoomsChunkRoom {
+    room_type?: RoomType | string;
+    children_state: IHierarchyRelation[];
+}
 /* eslint-enable camelcase */
@@ -25,4 +25,5 @@ export interface IThreepid {
    address: string;
    validated_at: number; // eslint-disable-line camelcase
    added_at: number; // eslint-disable-line camelcase
+    bound?: boolean;
 }
@@ -16,21 +16,20 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

+// eslint-disable-next-line no-restricted-imports
 import { EventEmitter } from "events";

+import { ListenerMap, TypedEventEmitter } from "./models/typed-event-emitter";
+
 export class ReEmitter {
-    private target: EventEmitter;
+    constructor(private readonly target: EventEmitter) {}

-    constructor(target: EventEmitter) {
-        this.target = target;
-    }
-
-    reEmit(source: EventEmitter, eventNames: string[]) {
+    public reEmit(source: EventEmitter, eventNames: string[]): void {
        for (const eventName of eventNames) {
            // We include the source as the last argument for event handlers which may need it,
            // such as read receipt listeners on the client class which won't have the context
            // of the room.
-            const forSource = (...args) => {
+            const forSource = (...args: any[]) => {
                // EventEmitter special cases 'error' to make the emit function throw if no
                // handler is attached, which sort of makes sense for making sure that something
                // handles an error, but for re-emitting, there could be a listener on the original
@@ -48,3 +47,19 @@ export class ReEmitter {
        }
    }
 }
+
+export class TypedReEmitter<
+    Events extends string,
+    Arguments extends ListenerMap<Events>,
+> extends ReEmitter {
+    constructor(target: TypedEventEmitter<Events, Arguments>) {
+        super(target);
+    }
+
+    public reEmit<ReEmittedEvents extends string, T extends Events & ReEmittedEvents>(
+        source: TypedEventEmitter<ReEmittedEvents, any>,
+        eventNames: T[],
+    ): void {
+        super.reEmit(source, eventNames);
+    }
+}
@@ -17,79 +17,20 @@ limitations under the License.

 /** @module auto-discovery */

-import { logger } from './logger';
 import { URL as NodeURL } from "url";

+import { IClientWellKnown, IWellKnownConfig } from "./client";
+import { logger } from './logger';
+
 // Dev note: Auto discovery is part of the spec.
 // See: https://matrix.org/docs/spec/client_server/r0.4.0.html#server-discovery

-/**
- * Description for what an automatically discovered client configuration
- * would look like. Although this is a class, it is recommended that it
- * be treated as an interface definition rather than as a class.
- *
- * Additional properties than those defined here may be present, and
- * should follow the Java package naming convention.
- */
-class DiscoveredClientConfig { // eslint-disable-line no-unused-vars
-    // Dev note: this is basically a copy/paste of the .well-known response
-    // object as defined in the spec. It does have additional information,
-    // however. Overall, this exists to serve as a place for documentation
-    // and not functionality.
-    // See https://matrix.org/docs/spec/client_server/r0.4.0.html#get-well-known-matrix-client
-
-    constructor() {
-        /**
-         * The homeserver configuration the client should use. This will
-         * always be present on the object.
-         * @type {{state: string, base_url: string}} The configuration.
-         */
-        this["m.homeserver"] = {
-            /**
-             * The lookup result state. If this is anything other than
-             * AutoDiscovery.SUCCESS then base_url may be falsey. Additionally,
-             * if this is not AutoDiscovery.SUCCESS then the client should
-             * assume the other properties in the client config (such as
-             * the identity server configuration) are not valid.
-             */
-            state: AutoDiscovery.PROMPT,
-
-            /**
-             * If the state is AutoDiscovery.FAIL_ERROR or .FAIL_PROMPT
-             * then this will contain a human-readable (English) message
-             * for what went wrong. If the state is none of those previously
-             * mentioned, this will be falsey.
-             */
-            error: "Something went wrong",
-
-            /**
-             * The base URL clients should use to talk to the homeserver,
-             * particularly for the login process. May be falsey if the
-             * state is not AutoDiscovery.SUCCESS.
-             */
-            base_url: "https://matrix.org",
-        };
-
-        /**
-         * The identity server configuration the client should use. This
-         * will always be present on teh object.
-         * @type {{state: string, base_url: string}} The configuration.
-         */
-        this["m.identity_server"] = {
-            /**
-             * The lookup result state. If this is anything other than
-             * AutoDiscovery.SUCCESS then base_url may be falsey.
-             */
-            state: AutoDiscovery.PROMPT,
-
-            /**
-             * The base URL clients should use for interacting with the
-             * identity server. May be falsey if the state is not
-             * AutoDiscovery.SUCCESS.
-             */
-            base_url: "https://vector.im",
-        };
-    }
+export enum AutoDiscoveryAction {
+    SUCCESS = "SUCCESS",
+    IGNORE = "IGNORE",
+    PROMPT = "PROMPT",
+    FAIL_PROMPT = "FAIL_PROMPT",
+    FAIL_ERROR = "FAIL_ERROR",
 }

 /**
@@ -102,55 +43,36 @@ export class AutoDiscovery {
    // translate the meaning of the states in the spec, but also
    // support our own if needed.

-    static get ERROR_INVALID() {
-        return "Invalid homeserver discovery response";
-    }
+    public static readonly ERROR_INVALID = "Invalid homeserver discovery response";

-    static get ERROR_GENERIC_FAILURE() {
-        return "Failed to get autodiscovery configuration from server";
-    }
+    public static readonly ERROR_GENERIC_FAILURE = "Failed to get autodiscovery configuration from server";

-    static get ERROR_INVALID_HS_BASE_URL() {
-        return "Invalid base_url for m.homeserver";
-    }
+    public static readonly ERROR_INVALID_HS_BASE_URL = "Invalid base_url for m.homeserver";

-    static get ERROR_INVALID_HOMESERVER() {
-        return "Homeserver URL does not appear to be a valid Matrix homeserver";
-    }
+    public static readonly ERROR_INVALID_HOMESERVER = "Homeserver URL does not appear to be a valid Matrix homeserver";

-    static get ERROR_INVALID_IS_BASE_URL() {
-        return "Invalid base_url for m.identity_server";
-    }
+    public static readonly ERROR_INVALID_IS_BASE_URL = "Invalid base_url for m.identity_server";

-    static get ERROR_INVALID_IDENTITY_SERVER() {
-        return "Identity server URL does not appear to be a valid identity server";
-    }
+    // eslint-disable-next-line
+    public static readonly ERROR_INVALID_IDENTITY_SERVER = "Identity server URL does not appear to be a valid identity server";

-    static get ERROR_INVALID_IS() {
-        return "Invalid identity server discovery response";
-    }
+    public static readonly ERROR_INVALID_IS = "Invalid identity server discovery response";

-    static get ERROR_MISSING_WELLKNOWN() {
-        return "No .well-known JSON file found";
-    }
+    public static readonly ERROR_MISSING_WELLKNOWN = "No .well-known JSON file found";

-    static get ERROR_INVALID_JSON() {
-        return "Invalid JSON";
-    }
+    public static readonly ERROR_INVALID_JSON = "Invalid JSON";

-    static get ALL_ERRORS() {
-        return [
-            AutoDiscovery.ERROR_INVALID,
-            AutoDiscovery.ERROR_GENERIC_FAILURE,
-            AutoDiscovery.ERROR_INVALID_HS_BASE_URL,
-            AutoDiscovery.ERROR_INVALID_HOMESERVER,
-            AutoDiscovery.ERROR_INVALID_IS_BASE_URL,
-            AutoDiscovery.ERROR_INVALID_IDENTITY_SERVER,
-            AutoDiscovery.ERROR_INVALID_IS,
-            AutoDiscovery.ERROR_MISSING_WELLKNOWN,
-            AutoDiscovery.ERROR_INVALID_JSON,
-        ];
-    }
+    public static readonly ALL_ERRORS = [
+        AutoDiscovery.ERROR_INVALID,
+        AutoDiscovery.ERROR_GENERIC_FAILURE,
+        AutoDiscovery.ERROR_INVALID_HS_BASE_URL,
+        AutoDiscovery.ERROR_INVALID_HOMESERVER,
+        AutoDiscovery.ERROR_INVALID_IS_BASE_URL,
+        AutoDiscovery.ERROR_INVALID_IDENTITY_SERVER,
+        AutoDiscovery.ERROR_INVALID_IS,
+        AutoDiscovery.ERROR_MISSING_WELLKNOWN,
+        AutoDiscovery.ERROR_INVALID_JSON,
+    ];

    /**
     * The auto discovery failed. The client is expected to communicate
@@ -158,7 +80,7 @@ export class AutoDiscovery {
     * @return {string}
     * @constructor
     */
-    static get FAIL_ERROR() { return "FAIL_ERROR"; }
+    public static readonly FAIL_ERROR = AutoDiscoveryAction.FAIL_ERROR;

    /**
     * The auto discovery failed, however the client may still recover
@@ -169,7 +91,7 @@ export class AutoDiscovery {
     * @return {string}
     * @constructor
     */
-    static get FAIL_PROMPT() { return "FAIL_PROMPT"; }
+    public static readonly FAIL_PROMPT = AutoDiscoveryAction.FAIL_PROMPT;

    /**
     * The auto discovery didn't fail but did not find anything of
@@ -178,14 +100,14 @@ export class AutoDiscovery {
     * @return {string}
     * @constructor
     */
-    static get PROMPT() { return "PROMPT"; }
+    public static readonly PROMPT = AutoDiscoveryAction.PROMPT;

    /**
     * The auto discovery was successful.
     * @return {string}
     * @constructor
     */
-    static get SUCCESS() { return "SUCCESS"; }
+    public static readonly SUCCESS = AutoDiscoveryAction.SUCCESS;

    /**
     * Validates and verifies client configuration information for purposes
@@ -193,13 +115,13 @@ export class AutoDiscovery {
     * and identity server URL the client would want. Additional details
     * may also be included, and will be transparently brought into the
     * response object unaltered.
-     * @param {string} wellknown The configuration object itself, as returned
+     * @param {object} wellknown The configuration object itself, as returned
     * by the .well-known auto-discovery endpoint.
     * @return {Promise<DiscoveredClientConfig>} Resolves to the verified
     * configuration, which may include error states. Rejects on unexpected
     * failure, not when verification fails.
     */
-    static async fromDiscoveryConfig(wellknown) {
+    public static async fromDiscoveryConfig(wellknown: any): Promise<IClientWellKnown> {
        // Step 1 is to get the config, which is provided to us here.

        // We default to an error state to make the first few checks easier to
@@ -240,7 +162,7 @@ export class AutoDiscovery {

        // Step 2: Make sure the homeserver URL is valid *looking*. We'll make
        // sure it points to a homeserver in Step 3.
-        const hsUrl = this._sanitizeWellKnownUrl(
+        const hsUrl = this.sanitizeWellKnownUrl(
            wellknown["m.homeserver"]["base_url"],
        );
        if (!hsUrl) {
@@ -250,7 +172,7 @@ export class AutoDiscovery {
        }

        // Step 3: Make sure the homeserver URL points to a homeserver.
-        const hsVersions = await this._fetchWellKnownObject(
+        const hsVersions = await this.fetchWellKnownObject(
            `${hsUrl}/_matrix/client/versions`,
        );
        if (!hsVersions || !hsVersions.raw["versions"]) {
@@ -272,7 +194,7 @@ export class AutoDiscovery {
        };

        // Step 5: Try to pull out the identity server configuration
-        let isUrl = "";
+        let isUrl: string | boolean = "";
        if (wellknown["m.identity_server"]) {
            // We prepare a failing identity server response to save lines later
            // in this branch.
@@ -287,7 +209,7 @@ export class AutoDiscovery {

            // Step 5a: Make sure the URL is valid *looking*. We'll make sure it
            // points to an identity server in Step 5b.
-            isUrl = this._sanitizeWellKnownUrl(
+            isUrl = this.sanitizeWellKnownUrl(
                wellknown["m.identity_server"]["base_url"],
            );
            if (!isUrl) {
@@ -299,10 +221,10 @@ export class AutoDiscovery {

            // Step 5b: Verify there is an identity server listening on the provided
            // URL.
-            const isResponse = await this._fetchWellKnownObject(
+            const isResponse = await this.fetchWellKnownObject(
                `${isUrl}/_matrix/identity/api/v1`,
            );
-            if (!isResponse || !isResponse.raw || isResponse.action !== "SUCCESS") {
+            if (!isResponse || !isResponse.raw || isResponse.action !== AutoDiscoveryAction.SUCCESS) {
                logger.error("Invalid /api/v1 response");
                failingClientConfig["m.identity_server"].error =
                    AutoDiscovery.ERROR_INVALID_IDENTITY_SERVER;
@@ -317,7 +239,7 @@ export class AutoDiscovery {

        // Step 6: Now that the identity server is valid, or never existed,
        // populate the IS section.
-        if (isUrl && isUrl.length > 0) {
+        if (isUrl && isUrl.toString().length > 0) {
            clientConfig["m.identity_server"] = {
                state: AutoDiscovery.SUCCESS,
                error: null,
@@ -359,7 +281,7 @@ export class AutoDiscovery {
     * configuration, which may include error states. Rejects on unexpected
     * failure, not when discovery fails.
     */
-    static async findClientConfig(domain) {
+    public static async findClientConfig(domain: string): Promise<IClientWellKnown> {
        if (!domain || typeof(domain) !== "string" || domain.length === 0) {
            throw new Error("'domain' must be a string of non-zero length");
        }
@@ -395,13 +317,13 @@ export class AutoDiscovery {

        // Step 1: Actually request the .well-known JSON file and make sure it
        // at least has a homeserver definition.
-        const wellknown = await this._fetchWellKnownObject(
+        const wellknown = await this.fetchWellKnownObject(
            `https://${domain}/.well-known/matrix/client`,
        );
-        if (!wellknown || wellknown.action !== "SUCCESS") {
+        if (!wellknown || wellknown.action !== AutoDiscoveryAction.SUCCESS) {
            logger.error("No response or error when parsing .well-known");
            if (wellknown.reason) logger.error(wellknown.reason);
-            if (wellknown.action === "IGNORE") {
+            if (wellknown.action === AutoDiscoveryAction.IGNORE) {
                clientConfig["m.homeserver"] = {
                    state: AutoDiscovery.PROMPT,
                    error: null,
@@ -427,12 +349,12 @@ export class AutoDiscovery {
     * @returns {Promise<object>} Resolves to the domain's client config. Can
     * be an empty object.
     */
-    static async getRawClientConfig(domain) {
+    public static async getRawClientConfig(domain: string): Promise<IClientWellKnown> {
        if (!domain || typeof(domain) !== "string" || domain.length === 0) {
            throw new Error("'domain' must be a string of non-zero length");
        }

-        const response = await this._fetchWellKnownObject(
+        const response = await this.fetchWellKnownObject(
            `https://${domain}/.well-known/matrix/client`,
        );
        if (!response) return {};
@@ -447,7 +369,7 @@ export class AutoDiscovery {
     * @return {string|boolean} The sanitized URL or a falsey value if the URL is invalid.
     * @private
     */
-    static _sanitizeWellKnownUrl(url) {
+    private static sanitizeWellKnownUrl(url: string): string | boolean {
        if (!url) return false;

        try {
@@ -495,8 +417,9 @@ export class AutoDiscovery {
     * @return {Promise<object>} Resolves to the returned state.
     * @private
     */
-    static async _fetchWellKnownObject(url) {
+    private static async fetchWellKnownObject(url: string): Promise<IWellKnownConfig> {
        return new Promise(function(resolve, reject) {
+            // eslint-disable-next-line
            const request = require("./matrix").getRequest();
            if (!request) throw new Error("No request library available");
            request(
@@ -505,10 +428,10 @@ export class AutoDiscovery {
                    if (err || response &&
                        (response.statusCode < 200 || response.statusCode >= 300)
                    ) {
-                        let action = "FAIL_PROMPT";
+                        let action = AutoDiscoveryAction.FAIL_PROMPT;
                        let reason = (err ? err.message : null) || "General failure";
                        if (response && response.statusCode === 404) {
-                            action = "IGNORE";
+                            action = AutoDiscoveryAction.IGNORE;
                            reason = AutoDiscovery.ERROR_MISSING_WELLKNOWN;
                        }
                        resolve({ raw: {}, action: action, reason: reason, error: err });
@@ -516,7 +439,7 @@ export class AutoDiscovery {
                    }

                    try {
-                        resolve({ raw: JSON.parse(body), action: "SUCCESS" });
+                        resolve({ raw: JSON.parse(body), action: AutoDiscoveryAction.SUCCESS });
                    } catch (e) {
                        let reason = AutoDiscovery.ERROR_INVALID;
                        if (e.name === "SyntaxError") {
@@ -524,7 +447,7 @@ export class AutoDiscovery {
                        }
                        resolve({
                            raw: {},
-                            action: "FAIL_PROMPT",
+                            action: AutoDiscoveryAction.FAIL_PROMPT,
                            reason: reason,
                            error: e,
                        });
@@ -14,10 +14,15 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-import * as matrixcs from "./matrix";
 import request from "browser-request";
 import queryString from "qs";

+import * as matrixcs from "./matrix";
+
+if (matrixcs.getRequest()) {
+    throw new Error("Multiple matrix-js-sdk entrypoints detected!");
+}
+
 matrixcs.request(function(opts, fn) {
    // We manually fix the query string for browser-request because
    // it doesn't correctly handle cases like ?via=one&via=two. Instead
@@ -1,6 +1,5 @@
 /*
-Copyright 2018 New Vector Ltd
-Copyright 2018 - 2021 The Matrix.org Foundation C.I.C.
+Copyright 2018 - 2022 The Matrix.org Foundation C.I.C.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -18,6 +17,14 @@ limitations under the License.
 /** @module ContentHelpers */

 import { MsgType } from "./@types/event";
+import { TEXT_NODE_TYPE } from "./@types/extensible_events";
+import {
+    ASSET_NODE_TYPE,
+    ILocationContent,
+    LocationAssetType,
+    LOCATION_EVENT_TYPE,
+    TIMESTAMP_NODE_TYPE,
+} from "./@types/location";

 /**
 * Generates the content for a HTML Message event
@@ -99,3 +106,36 @@ export function makeEmoteMessage(body: string) {
        body: body,
    };
 }
+
+/**
+ * Generates the content for a Location event
+ * @param text a text for of our location
+ * @param uri a geo:// uri for the location
+ * @param ts the timestamp when the location was correct (milliseconds since
+ *           the UNIX epoch)
+ * @param description the (optional) label for this location on the map
+ * @param asset_type the (optional) asset type of this location e.g. "m.self"
+ */
+export function makeLocationContent(
+    text: string,
+    uri: string,
+    ts: number,
+    description?: string,
+    assetType?: LocationAssetType,
+): ILocationContent {
+    return {
+        "body": text,
+        "msgtype": MsgType.Location,
+        "geo_uri": uri,
+        [LOCATION_EVENT_TYPE.name]: {
+            uri,
+            description,
+        },
+        [ASSET_NODE_TYPE.name]: {
+            type: assetType ?? LocationAssetType.Self,
+        },
+        [TEXT_NODE_TYPE.name]: text,
+        [TIMESTAMP_NODE_TYPE.name]: ts,
+        // TODO: MSC1767 fallbacks m.image thumbnail
+    };
+}
@@ -53,13 +53,13 @@ export function getHttpUriForMxc(
    }
    let serverAndMediaId = mxc.slice(6); // strips mxc://
    let prefix = "/_matrix/media/r0/download/";
-    const params = {};
+    const params: Record<string, string> = {};

    if (width) {
-        params["width"] = Math.round(width);
+        params["width"] = Math.round(width).toString();
    }
    if (height) {
-        params["height"] = Math.round(height);
+        params["height"] = Math.round(height).toString();
    }
    if (resizeMethod) {
        params["method"] = resizeMethod;
@@ -19,13 +19,12 @@ limitations under the License.
 * @module crypto/CrossSigning
 */

-import { EventEmitter } from 'events';
+import { PkSigning } from "@matrix-org/olm";

 import { decodeBase64, encodeBase64, pkSign, pkVerify } from './olmlib';
 import { logger } from '../logger';
 import { IndexedDBCryptoStore } from '../crypto/store/indexeddb-crypto-store';
 import { decryptAES, encryptAES } from './aes';
-import { PkSigning } from "@matrix-org/olm";
 import { DeviceInfo } from "./deviceinfo";
 import { SecretStorage } from "./SecretStorage";
 import { ICrossSigningKey, ISignedKey, MatrixClient } from "../client";
@@ -33,6 +32,7 @@ import { OlmDevice } from "./OlmDevice";
 import { ICryptoCallbacks } from "../matrix";
 import { ISignatures } from "../@types/signed";
 import { CryptoStore } from "./store/base";
+import { ISecretStorageKeyInfo } from "./api";

 const KEY_REQUEST_TIMEOUT_MS = 1000 * 60;

@@ -54,7 +54,7 @@ export interface ICrossSigningInfo {
    crossSigningVerifiedBefore: boolean;
 }

-export class CrossSigningInfo extends EventEmitter {
+export class CrossSigningInfo {
    public keys: Record<string, ICrossSigningKey> = {};
    public firstUse = true;
    // This tracks whether we've ever verified this user with any identity.
@@ -78,9 +78,7 @@ export class CrossSigningInfo extends EventEmitter {
        public readonly userId: string,
        private callbacks: ICryptoCallbacks = {},
        private cacheCallbacks: ICacheCallbacks = {},
-    ) {
-        super();
-    }
+    ) {}

    public static fromStorage(obj: ICrossSigningInfo, userId: string): CrossSigningInfo {
        const res = new CrossSigningInfo(userId);
@@ -175,7 +173,7 @@ export class CrossSigningInfo extends EventEmitter {
        // check what SSSS keys have encrypted the master key (if any)
        const stored = await secretStorage.isStored("m.cross_signing.master", false) || {};
        // then check which of those SSSS keys have also encrypted the SSK and USK
-        function intersect(s) {
+        function intersect(s: Record<string, ISecretStorageKeyInfo>) {
            for (const k of Object.keys(stored)) {
                if (!s[k]) {
                    delete stored[k];
@@ -304,7 +302,7 @@ export class CrossSigningInfo extends EventEmitter {
        }

        const privateKeys: Record<string, Uint8Array> = {};
-        const keys: Record<string, any> = {}; // TODO types
+        const keys: Record<string, ICrossSigningKey> = {};
        let masterSigning;
        let masterPub;

@@ -713,7 +711,7 @@ export function createCryptoStoreCacheCallbacks(store: CryptoStore, olmDevice: O
            });

            if (key && key.ciphertext) {
-                const pickleKey = Buffer.from(olmDevice._pickleKey);
+                const pickleKey = Buffer.from(olmDevice.pickleKey);
                const decrypted = await decryptAES(key, pickleKey, type);
                return decodeBase64(decrypted);
            } else {
@@ -726,7 +724,7 @@ export function createCryptoStoreCacheCallbacks(store: CryptoStore, olmDevice: O
                    `storeCrossSigningKeyCache expects Uint8Array, got ${key}`,
                );
            }
-            const pickleKey = Buffer.from(olmDevice._pickleKey);
+            const pickleKey = Buffer.from(olmDevice.pickleKey);
            const encryptedKey = await encryptAES(encodeBase64(key), pickleKey, type);
            return store.doTxn(
                'readwrite',
@@ -739,6 +737,8 @@ export function createCryptoStoreCacheCallbacks(store: CryptoStore, olmDevice: O
    };
 }

+export type KeysDuringVerification = [[string, PkSigning], [string, PkSigning], [string, PkSigning], void];
+
 /**
 * Request cross-signing keys from another device during verification.
 *
@@ -746,15 +746,19 @@ export function createCryptoStoreCacheCallbacks(store: CryptoStore, olmDevice: O
 * @param {string} userId The user ID being verified
 * @param {string} deviceId The device ID being verified
 */
-export async function requestKeysDuringVerification(baseApis: MatrixClient, userId: string, deviceId: string) {
+export function requestKeysDuringVerification(
+    baseApis: MatrixClient,
+    userId: string,
+    deviceId: string,
+): Promise<KeysDuringVerification | void> {
    // If this is a self-verification, ask the other party for keys
    if (baseApis.getUserId() !== userId) {
        return;
    }
    logger.log("Cross-signing: Self-verification done; requesting keys");
    // This happens asynchronously, and we're not concerned about waiting for
-    // it.  We return here in order to test.
-    return new Promise((resolve, reject) => {
+    // it. We return here in order to test.
+    return new Promise<KeysDuringVerification | void>((resolve, reject) => {
        const client = baseApis;
        const original = client.crypto.crossSigningInfo;

@@ -781,7 +785,7 @@ export async function requestKeysDuringVerification(baseApis: MatrixClient, user
        // https://github.com/vector-im/element-web/issues/12604
        // then change here to reject on the timeout
        // Requests can be ignored, so don't wait around forever
-        const timeout = new Promise((resolve, reject) => {
+        const timeout = new Promise<void>((resolve) => {
            setTimeout(
                resolve,
                KEY_REQUEST_TIMEOUT_MS,
@@ -801,7 +805,7 @@ export async function requestKeysDuringVerification(baseApis: MatrixClient, user
                logger.info("Got key backup key, decoding...");
                const decodedKey = decodeBase64(base64Key);
                logger.info("Decoded backup key, storing...");
-                client.crypto.storeSessionBackupPrivateKey(
+                await client.crypto.storeSessionBackupPrivateKey(
                    Uint8Array.from(decodedKey),
                );
                logger.info("Backup key stored. Starting backup restore...");
@@ -814,13 +818,13 @@ export async function requestKeysDuringVerification(baseApis: MatrixClient, user
        })();

        // We call getCrossSigningKey() for its side-effects
-        return Promise.race([
+        return Promise.race<KeysDuringVerification | void>([
            Promise.all([
                crossSigning.getCrossSigningKey("master"),
                crossSigning.getCrossSigningKey("self_signing"),
                crossSigning.getCrossSigningKey("user_signing"),
                backupKeyPromise,
-            ]),
+            ]) as Promise<KeysDuringVerification>,
            timeout,
        ]).then(resolve, reject);
    }).catch((e) => {
@@ -20,17 +20,17 @@ limitations under the License.
 * Manages the list of other users' devices
 */

-import { EventEmitter } from 'events';
-
 import { logger } from '../logger';
 import { DeviceInfo, IDevice } from './deviceinfo';
 import { CrossSigningInfo, ICrossSigningInfo } from './CrossSigning';
 import * as olmlib from './olmlib';
 import { IndexedDBCryptoStore } from './store/indexeddb-crypto-store';
 import { chunkPromises, defer, IDeferred, sleep } from '../utils';
-import { MatrixClient } from "../client";
+import { IDownloadKeyResult, MatrixClient } from "../client";
 import { OlmDevice } from "./OlmDevice";
 import { CryptoStore } from "./store/base";
+import { TypedEventEmitter } from "../models/typed-event-emitter";
+import { CryptoEvent, CryptoEventHandlerMap } from "./index";

 /* State transition diagram for DeviceList.deviceTrackingStatus
 *
@@ -62,10 +62,12 @@ export enum TrackingStatus {

 export type DeviceInfoMap = Record<string, Record<string, DeviceInfo>>;

+type EmittedEvents = CryptoEvent.WillUpdateDevices | CryptoEvent.DevicesUpdated | CryptoEvent.UserCrossSigningUpdated;
+
 /**
 * @alias module:crypto/DeviceList
 */
-export class DeviceList extends EventEmitter {
+export class DeviceList extends TypedEventEmitter<EmittedEvents, CryptoEventHandlerMap> {
    private devices: { [userId: string]: { [deviceId: string]: IDevice } } = {};

    public crossSigningInfo: { [userId: string]: ICrossSigningInfo } = {};
@@ -265,8 +267,8 @@ export class DeviceList extends EventEmitter {
     * module:crypto/deviceinfo|DeviceInfo}.
     */
    public downloadKeys(userIds: string[], forceDownload: boolean): Promise<DeviceInfoMap> {
-        const usersToDownload = [];
-        const promises = [];
+        const usersToDownload: string[] = [];
+        const promises: Promise<unknown>[] = [];

        userIds.forEach((u) => {
            const trackingStatus = this.deviceTrackingStatus[u];
@@ -633,8 +635,8 @@ export class DeviceList extends EventEmitter {
            }
        });

-        const finished = (success) => {
-            this.emit("crypto.willUpdateDevices", users, !this.hasFetched);
+        const finished = (success: boolean): void => {
+            this.emit(CryptoEvent.WillUpdateDevices, users, !this.hasFetched);
            users.forEach((u) => {
                this.dirty = true;

@@ -659,7 +661,7 @@ export class DeviceList extends EventEmitter {
                }
            });
            this.saveIfDirty();
-            this.emit("crypto.devicesUpdated", users, !this.hasFetched);
+            this.emit(CryptoEvent.DevicesUpdated, users, !this.hasFetched);
            this.hasFetched = true;
        };

@@ -756,17 +758,21 @@ class DeviceListUpdateSerialiser {
            opts.token = this.syncToken;
        }

-        const factories = [];
+        const factories: Array<() => Promise<IDownloadKeyResult>> = [];
        for (let i = 0; i < downloadUsers.length; i += this.deviceList.keyDownloadChunkSize) {
            const userSlice = downloadUsers.slice(i, i + this.deviceList.keyDownloadChunkSize);
            factories.push(() => this.baseApis.downloadKeysForUsers(userSlice, opts));
        }

-        chunkPromises(factories, 3).then(async (responses: any[]) => {
-            const dk = Object.assign({}, ...(responses.map(res => res.device_keys || {})));
-            const masterKeys = Object.assign({}, ...(responses.map(res => res.master_keys || {})));
-            const ssks = Object.assign({}, ...(responses.map(res => res.self_signing_keys || {})));
-            const usks = Object.assign({}, ...(responses.map(res => res.user_signing_keys || {})));
+        chunkPromises(factories, 3).then(async (responses: IDownloadKeyResult[]) => {
+            const dk: IDownloadKeyResult["device_keys"]
+                = Object.assign({}, ...(responses.map(res => res.device_keys || {})));
+            const masterKeys: IDownloadKeyResult["master_keys"]
+                = Object.assign({}, ...(responses.map(res => res.master_keys || {})));
+            const ssks: IDownloadKeyResult["self_signing_keys"]
+                = Object.assign({}, ...(responses.map(res => res.self_signing_keys || {})));
+            const usks: IDownloadKeyResult["user_signing_keys"]
+                = Object.assign({}, ...(responses.map(res => res.user_signing_keys || {})));

            // yield to other things that want to execute in between users, to
            // avoid wedging the CPU
@@ -811,8 +817,12 @@ class DeviceListUpdateSerialiser {

    private async processQueryResponseForUser(
        userId: string,
-        dkResponse: object,
-        crossSigningResponse: any, // TODO types
+        dkResponse: IDownloadKeyResult["device_keys"]["user_id"],
+        crossSigningResponse: {
+            master: IDownloadKeyResult["master_keys"]["user_id"];
+            self_signing: IDownloadKeyResult["master_keys"]["user_id"]; // eslint-disable-line camelcase
+            user_signing: IDownloadKeyResult["user_signing_keys"]["user_id"]; // eslint-disable-line camelcase
+        },
    ): Promise<void> {
        logger.log('got device keys for ' + userId + ':', dkResponse);
        logger.log('got cross-signing keys for ' + userId + ':', crossSigningResponse);
@@ -859,7 +869,7 @@ class DeviceListUpdateSerialiser {

                // NB. Unlike most events in the js-sdk, this one is internal to the
                // js-sdk and is not re-emitted
-                this.deviceList.emit('userCrossSigningUpdated', userId);
+                this.deviceList.emit(CryptoEvent.UserCrossSigningUpdated, userId);
            }
        }
    }
@@ -869,7 +879,7 @@ async function updateStoredDeviceKeysForUser(
    olmDevice: OlmDevice,
    userId: string,
    userStore: Record<string, DeviceInfo>,
-    userResult: object,
+    userResult: IDownloadKeyResult["device_keys"]["user_id"],
    localUserId: string,
    localDeviceId: string,
 ): Promise<boolean> {
@@ -16,13 +16,14 @@ limitations under the License.

 import { logger } from "../logger";
 import { MatrixEvent } from "../models/event";
-import { EventEmitter } from "events";
 import { createCryptoStoreCacheCallbacks, ICacheCallbacks } from "./CrossSigning";
 import { IndexedDBCryptoStore } from './store/indexeddb-crypto-store';
-import { PREFIX_UNSTABLE } from "../http-api";
+import { Method, PREFIX_UNSTABLE } from "../http-api";
 import { Crypto, IBootstrapCrossSigningOpts } from "./index";
 import {
+    ClientEvent,
    CrossSigningKeys,
+    ClientEventHandlerMap,
    ICrossSigningKey,
    ICryptoCallbacks,
    ISignedKey,
@@ -30,6 +31,8 @@ import {
 } from "../matrix";
 import { ISecretStorageKeyInfo } from "./api";
 import { IKeyBackupInfo } from "./keybackup";
+import { TypedEventEmitter } from "../models/typed-event-emitter";
+import { IAccountDataClient } from "./SecretStorage";

 interface ICrossSigningKeys {
    authUpload: IBootstrapCrossSigningOpts["authUploadDeviceSigningKeys"];
@@ -59,7 +62,7 @@ export class EncryptionSetupBuilder {
     * @param {Object.<String, MatrixEvent>} accountData pre-existing account data, will only be read, not written.
     * @param {CryptoCallbacks} delegateCryptoCallbacks crypto callbacks to delegate to if the key isn't in cache yet
     */
-    constructor(accountData: Record<string, MatrixEvent>, delegateCryptoCallbacks: ICryptoCallbacks) {
+    constructor(accountData: Record<string, MatrixEvent>, delegateCryptoCallbacks?: ICryptoCallbacks) {
        this.accountDataClientAdapter = new AccountDataClientAdapter(accountData);
        this.crossSigningCallbacks = new CrossSigningCallbacks();
        this.ssssCryptoCallbacks = new SSSSCryptoCallbacks(delegateCryptoCallbacks);
@@ -238,7 +241,7 @@ export class EncryptionSetupOperation {
                // Sign the backup with the cross signing key so the key backup can
                // be trusted via cross-signing.
                await baseApis.http.authedRequest(
-                    undefined, "PUT", "/room_keys/version/" + this.keyBackupInfo.version,
+                    undefined, Method.Put, "/room_keys/version/" + this.keyBackupInfo.version,
                    undefined, {
                        algorithm: this.keyBackupInfo.algorithm,
                        auth_data: this.keyBackupInfo.auth_data,
@@ -248,7 +251,7 @@ export class EncryptionSetupOperation {
            } else {
                // add new key backup
                await baseApis.http.authedRequest(
-                    undefined, "POST", "/room_keys/version",
+                    undefined, Method.Post, "/room_keys/version",
                    undefined, this.keyBackupInfo,
                    { prefix: PREFIX_UNSTABLE },
                );
@@ -261,7 +264,10 @@ export class EncryptionSetupOperation {
 * Catches account data set by SecretStorage during bootstrapping by
 * implementing the methods related to account data in MatrixClient
 */
-class AccountDataClientAdapter extends EventEmitter {
+class AccountDataClientAdapter
+    extends TypedEventEmitter<ClientEvent.AccountData, ClientEventHandlerMap>
+    implements IAccountDataClient {
+    //
    public readonly values = new Map<string, MatrixEvent>();

    /**
@@ -308,7 +314,7 @@ class AccountDataClientAdapter extends EventEmitter {
        // and it seems to rely on this.
        return Promise.resolve().then(() => {
            const event = new MatrixEvent({ type, content });
-            this.emit("accountData", event, lastEvent);
+            this.emit(ClientEvent.AccountData, event, lastEvent);
            return {};
        });
    }
@@ -351,12 +357,12 @@ class CrossSigningCallbacks implements ICryptoCallbacks, ICacheCallbacks {
 class SSSSCryptoCallbacks {
    private readonly privateKeys = new Map<string, Uint8Array>();

-    constructor(private readonly delegateCryptoCallbacks: ICryptoCallbacks) {}
+    constructor(private readonly delegateCryptoCallbacks?: ICryptoCallbacks) {}

    public async getSecretStorageKey(
        { keys }: { keys: Record<string, ISecretStorageKeyInfo> },
        name: string,
-    ): Promise<[string, Uint8Array]> {
+    ): Promise<[string, Uint8Array]|null> {
        for (const keyId of Object.keys(keys)) {
            const privateKey = this.privateKeys.get(keyId);
            if (privateKey) {
@@ -365,7 +371,7 @@ class SSSSCryptoCallbacks {
        }
        // if we don't have the key cached yet, ask
        // for it to the general crypto callbacks and cache it
-        if (this.delegateCryptoCallbacks) {
+        if (this?.delegateCryptoCallbacks?.getSecretStorageKey) {
            const result = await this.delegateCryptoCallbacks.
                getSecretStorageKey({ keys }, name);
            if (result) {
@@ -374,6 +380,7 @@ class SSSSCryptoCallbacks {
            }
            return result;
        }
+        return null;
    }

    public addPrivateKey(keyId: string, keyInfo: ISecretStorageKeyInfo, privKey: Uint8Array): void {
@@ -16,12 +16,13 @@ limitations under the License.

 import { logger } from '../logger';
 import * as olmlib from './olmlib';
+import { encodeBase64 } from './olmlib';
 import { randomString } from '../randomstring';
-import { encryptAES, decryptAES, IEncryptedPayload, calculateKeyCheck } from './aes';
-import { encodeBase64 } from "./olmlib";
-import { ICryptoCallbacks, MatrixClient, MatrixEvent } from '../matrix';
+import { calculateKeyCheck, decryptAES, encryptAES, IEncryptedPayload } from './aes';
+import { ClientEvent, ICryptoCallbacks, MatrixEvent } from '../matrix';
+import { ClientEventHandlerMap, MatrixClient } from "../client";
 import { IAddSecretStorageKeyOpts, ISecretStorageKeyInfo } from './api';
-import { EventEmitter } from 'stream';
+import { TypedEventEmitter } from '../models/typed-event-emitter';

 export const SECRET_STORAGE_ALGORITHM_V1_AES = "m.secret_storage.v1.aes-hmac-sha2";

@@ -35,9 +36,9 @@ export interface ISecretRequest {
    cancel: (reason: string) => void;
 }

-export interface IAccountDataClient extends EventEmitter {
+export interface IAccountDataClient extends TypedEventEmitter<ClientEvent.AccountData, ClientEventHandlerMap> {
    // Subset of MatrixClient (which also uses any for the event content)
-    getAccountDataFromServer: (eventType: string) => Promise<Record<string, any>>;
+    getAccountDataFromServer: <T extends {[k: string]: any}>(eventType: string) => Promise<T>;
    getAccountData: (eventType: string) => MatrixEvent;
    setAccountData: (eventType: string, content: any) => Promise<{}>;
 }
@@ -54,6 +55,13 @@ interface IDecryptors {
    decrypt: (ciphertext: IEncryptedPayload) => Promise<string>;
 }

+interface ISecretInfo {
+    encrypted: {
+        // eslint-disable-next-line camelcase
+        key_id: IEncryptedPayload;
+    };
+}
+
 /**
 * Implements Secure Secret Storage and Sharing (MSC1946)
 * @module crypto/SecretStorage
@@ -75,8 +83,8 @@ export class SecretStorage {
        private readonly baseApis?: MatrixClient,
    ) {}

-    public async getDefaultKeyId(): Promise<string> {
-        const defaultKey = await this.accountDataAdapter.getAccountDataFromServer(
+    public async getDefaultKeyId(): Promise<string | null> {
+        const defaultKey = await this.accountDataAdapter.getAccountDataFromServer<{ key: string }>(
            'm.secret_storage.default_key',
        );
        if (!defaultKey) return null;
@@ -90,17 +98,17 @@ export class SecretStorage {
                    ev.getType() === 'm.secret_storage.default_key' &&
                    ev.getContent().key === keyId
                ) {
-                    this.accountDataAdapter.removeListener('accountData', listener);
+                    this.accountDataAdapter.removeListener(ClientEvent.AccountData, listener);
                    resolve();
                }
            };
-            this.accountDataAdapter.on('accountData', listener);
+            this.accountDataAdapter.on(ClientEvent.AccountData, listener);

            this.accountDataAdapter.setAccountData(
                'm.secret_storage.default_key',
                { key: keyId },
            ).catch(e => {
-                this.accountDataAdapter.removeListener('accountData', listener);
+                this.accountDataAdapter.removeListener(ClientEvent.AccountData, listener);
                reject(e);
            });
        });
@@ -149,7 +157,7 @@ export class SecretStorage {
            do {
                keyId = randomString(32);
            } while (
-                await this.accountDataAdapter.getAccountDataFromServer(
+                await this.accountDataAdapter.getAccountDataFromServer<ISecretStorageKeyInfo>(
                    `m.secret_storage.key.${keyId}`,
                )
            );
@@ -182,9 +190,9 @@ export class SecretStorage {
            return null;
        }

-        const keyInfo = await this.accountDataAdapter.getAccountDataFromServer(
+        const keyInfo = await this.accountDataAdapter.getAccountDataFromServer<ISecretStorageKeyInfo>(
            "m.secret_storage.key." + keyId,
-        ) as ISecretStorageKeyInfo;
+        );
        return keyInfo ? [keyId, keyInfo] : null;
    }

@@ -230,7 +238,7 @@ export class SecretStorage {
     *     or null/undefined to use the default key.
     */
    public async store(name: string, secret: string, keys?: string[]): Promise<void> {
-        const encrypted = {};
+        const encrypted: Record<string, IEncryptedPayload> = {};

        if (!keys) {
            const defaultKeyId = await this.getDefaultKeyId();
@@ -246,9 +254,9 @@ export class SecretStorage {

        for (const keyId of keys) {
            // get key information from key storage
-            const keyInfo = await this.accountDataAdapter.getAccountDataFromServer(
+            const keyInfo = await this.accountDataAdapter.getAccountDataFromServer<ISecretStorageKeyInfo>(
                "m.secret_storage.key." + keyId,
-            ) as ISecretStorageKeyInfo;
+            );
            if (!keyInfo) {
                throw new Error("Unknown key: " + keyId);
            }
@@ -277,7 +285,7 @@ export class SecretStorage {
     * @return {string} the contents of the secret
     */
    public async get(name: string): Promise<string> {
-        const secretInfo = await this.accountDataAdapter.getAccountDataFromServer(name);
+        const secretInfo = await this.accountDataAdapter.getAccountDataFromServer<ISecretInfo>(name);
        if (!secretInfo) {
            return;
        }
@@ -286,11 +294,13 @@ export class SecretStorage {
        }

        // get possible keys to decrypt
-        const keys = {};
+        const keys: Record<string, ISecretStorageKeyInfo> = {};
        for (const keyId of Object.keys(secretInfo.encrypted)) {
            // get key information from key storage
-            const keyInfo = await this.accountDataAdapter.getAccountDataFromServer(
-                "m.secret_storage.key." + keyId,
+            const keyInfo = (
+                await this.accountDataAdapter.getAccountDataFromServer<ISecretStorageKeyInfo>(
+                    "m.secret_storage.key." + keyId,
+                )
            );
            const encInfo = secretInfo.encrypted[keyId];
            // only use keys we understand the encryption algorithm of
@@ -306,7 +316,7 @@ export class SecretStorage {
                `the keys it is encrypted with are for a supported algorithm`);
        }

-        let keyId;
+        let keyId: string;
        let decryption;
        try {
            // fetch private key from app
@@ -335,9 +345,9 @@ export class SecretStorage {
     *     with, or null if it is not present or not encrypted with a trusted
     *     key
     */
-    public async isStored(name: string, checkKey: boolean): Promise<Record<string, ISecretStorageKeyInfo>> {
+    public async isStored(name: string, checkKey: boolean): Promise<Record<string, ISecretStorageKeyInfo> | null> {
        // check if secret exists
-        const secretInfo = await this.accountDataAdapter.getAccountDataFromServer(name);
+        const secretInfo = await this.accountDataAdapter.getAccountDataFromServer<ISecretInfo>(name);
        if (!secretInfo) return null;
        if (!secretInfo.encrypted) {
            return null;
@@ -350,7 +360,7 @@ export class SecretStorage {
        // filter secret encryption keys with supported algorithm
        for (const keyId of Object.keys(secretInfo.encrypted)) {
            // get key information from key storage
-            const keyInfo = await this.accountDataAdapter.getAccountDataFromServer(
+            const keyInfo = await this.accountDataAdapter.getAccountDataFromServer<ISecretStorageKeyInfo>(
                "m.secret_storage.key." + keyId,
            );
            if (!keyInfo) continue;
@@ -375,8 +385,8 @@ export class SecretStorage {
    public request(name: string, devices: string[]): ISecretRequest {
        const requestId = this.baseApis.makeTxnId();

-        let resolve: (string) => void;
-        let reject: (Error) => void;
+        let resolve: (s: string) => void;
+        let reject: (e: Error) => void;
        const promise = new Promise<string>((res, rej) => {
            resolve = res;
            reject = rej;
@@ -15,7 +15,6 @@ limitations under the License.
 */

 import type { BinaryLike } from "crypto";
-
 import { getCrypto } from '../utils';
 import { decodeBase64, encodeBase64 } from './olmlib';

@@ -26,9 +25,10 @@ const subtleCrypto = (typeof window !== "undefined" && window.crypto) ?
 const zeroSalt = new Uint8Array(8);

 export interface IEncryptedPayload {
-    iv: string;
-    ciphertext: string;
-    mac: string;
+    [key: string]: any; // extensible
+    iv?: string;
+    ciphertext?: string;
+    mac?: string;
 }

 /**
@@ -46,7 +46,7 @@ type DecryptionClassParams = Omit<IParams, "deviceId" | "config">;
 */
 export const DECRYPTION_CLASSES: Record<string, new (params: DecryptionClassParams) => DecryptionAlgorithm> = {};

-interface IParams {
+export interface IParams {
    userId: string;
    deviceId: string;
    crypto: Crypto;
@@ -26,6 +26,7 @@ import {
    DecryptionAlgorithm,
    DecryptionError,
    EncryptionAlgorithm,
+    IParams,
    registerAlgorithm,
    UnknownDeviceError,
 } from "./base";
@@ -67,7 +68,7 @@ export interface IOlmDevice<T = DeviceInfo> {
 }

 /* eslint-disable camelcase */
-interface IOutboundGroupSessionKey {
+export interface IOutboundGroupSessionKey {
    chain_index: number;
    key: string;
 }
@@ -99,8 +100,21 @@ interface IPayload extends Partial<IMessage> {
    algorithm?: string;
    sender_key?: string;
 }
+
+interface IEncryptedContent {
+    algorithm: string;
+    sender_key: string;
+    ciphertext: Record<string, string>;
+}
 /* eslint-enable camelcase */

+interface SharedWithData {
+    // The identity key of the device we shared with
+    deviceKey: string;
+    // The message index of the ratchet we shared with that device
+    messageIndex: number;
+}
+
 /**
 * @private
 * @constructor
@@ -115,12 +129,12 @@ interface IPayload extends Partial<IMessage> {
 *
 * @property {object} sharedWithDevices
 *    devices with which we have shared the session key
- *        userId -> {deviceId -> msgindex}
+ *        userId -> {deviceId -> SharedWithData}
 */
 class OutboundSessionInfo {
    public useCount = 0;
    public creationTime: number;
-    public sharedWithDevices: Record<string, Record<string, number>> = {};
+    public sharedWithDevices: Record<string, Record<string, SharedWithData>> = {};
    public blockedDevicesNotified: Record<string, Record<string, boolean>> = {};

    constructor(public readonly sessionId: string, public readonly sharedHistory = false) {
@@ -150,11 +164,11 @@ class OutboundSessionInfo {
        return false;
    }

-    public markSharedWithDevice(userId: string, deviceId: string, chainIndex: number): void {
+    public markSharedWithDevice(userId: string, deviceId: string, deviceKey: string, chainIndex: number): void {
        if (!this.sharedWithDevices[userId]) {
            this.sharedWithDevices[userId] = {};
        }
-        this.sharedWithDevices[userId][deviceId] = chainIndex;
+        this.sharedWithDevices[userId][deviceId] = { deviceKey, messageIndex: chainIndex };
    }

    public markNotifiedBlockedDevice(userId: string, deviceId: string): void {
@@ -231,7 +245,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
        startTime: number;
    };

-    constructor(params) {
+    constructor(params: IParams) {
        super(params);

        this.sessionRotationPeriodMsgs = params.config?.rotation_period_msgs ?? 100;
@@ -256,7 +270,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
        blocked: IBlockedMap,
        singleOlmCreationPhase = false,
    ): Promise<OutboundSessionInfo> {
-        let session;
+        let session: OutboundSessionInfo;

        // takes the previous OutboundSessionInfo, and considers whether to create
        // a new one. Also shares the key with any (new) devices in the room.
@@ -295,7 +309,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
            }

            // now check if we need to share with any devices
-            const shareMap = {};
+            const shareMap: Record<string, DeviceInfo[]> = {};

            for (const [userId, userDevices] of Object.entries(devicesInRoom)) {
                for (const [deviceId, deviceInfo] of Object.entries(userDevices)) {
@@ -334,13 +348,16 @@ class MegolmEncryption extends EncryptionAlgorithm {
            await Promise.all([
                (async () => {
                    // share keys with devices that we already have a session for
-                    logger.debug(`Sharing keys with existing Olm sessions in ${this.roomId}`);
+                    logger.debug(`Sharing keys with existing Olm sessions in ${this.roomId}`, olmSessions);
                    await this.shareKeyWithOlmSessions(session, key, payload, olmSessions);
                    logger.debug(`Shared keys with existing Olm sessions in ${this.roomId}`);
                })(),
                (async () => {
-                    logger.debug(`Sharing keys (start phase 1) with new Olm sessions in ${this.roomId}`);
-                    const errorDevices = [];
+                    logger.debug(
+                        `Sharing keys (start phase 1) with new Olm sessions in ${this.roomId}`,
+                        devicesWithoutSession,
+                    );
+                    const errorDevices: IOlmDevice[] = [];

                    // meanwhile, establish olm sessions for devices that we don't
                    // already have a session for, and share keys with them.  If
@@ -348,7 +365,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
                    // shorter timeout when fetching one-time keys for the first
                    // phase.
                    const start = Date.now();
-                    const failedServers = [];
+                    const failedServers: string[] = [];
                    await this.shareKeyWithDevices(
                        session, key, payload, devicesWithoutSession, errorDevices,
                        singleOlmCreationPhase ? 10000 : 2000, failedServers,
@@ -364,7 +381,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
                            // do this in the background and don't block anything else while we
                            // do this.  We only need to retry users from servers that didn't
                            // respond the first time.
-                            const retryDevices = {};
+                            const retryDevices: Record<string, DeviceInfo[]> = {};
                            const failedServerMap = new Set;
                            for (const server of failedServers) {
                                failedServerMap.add(server);
@@ -396,8 +413,11 @@ class MegolmEncryption extends EncryptionAlgorithm {
                    logger.debug(`Shared keys (all phases done) with new Olm sessions in ${this.roomId}`);
                })(),
                (async () => {
-                    logger.debug(`Notifying blocked devices in ${this.roomId}`);
-                    // also, notify blocked devices that they're blocked
+                    logger.debug(`There are ${Object.entries(blocked).length} blocked devices in ${this.roomId}`,
+                        Object.entries(blocked));
+
+                    // also, notify newly blocked devices that they're blocked
+                    logger.debug(`Notifying newly blocked devices in ${this.roomId}`);
                    const blockedMap: Record<string, Record<string, { device: IBlockedDevice }>> = {};
                    let blockedCount = 0;
                    for (const [userId, userBlockedDevices] of Object.entries(blocked)) {
@@ -414,7 +434,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
                    }

                    await this.notifyBlockedDevices(session, blockedMap);
-                    logger.debug(`Notified ${blockedCount} blocked devices in ${this.roomId}`);
+                    logger.debug(`Notified ${blockedCount} newly blocked devices in ${this.roomId}`, blockedMap);
                })(),
            ]);
        };
@@ -571,11 +591,12 @@ class MegolmEncryption extends EncryptionAlgorithm {
        userDeviceMap: IOlmDevice[],
        payload: IPayload,
    ): Promise<void> {
-        const contentMap = {};
+        const contentMap: Record<string, Record<string, IEncryptedContent>> = {};
+        const deviceInfoByDeviceId = new Map<string, DeviceInfo>();

-        const promises = [];
+        const promises: Promise<unknown>[] = [];
        for (let i = 0; i < userDeviceMap.length; i++) {
-            const encryptedContent = {
+            const encryptedContent: IEncryptedContent = {
                algorithm: olmlib.OLM_ALGORITHM,
                sender_key: this.olmDevice.deviceCurve25519Key,
                ciphertext: {},
@@ -584,6 +605,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
            const userId = val.userId;
            const deviceInfo = val.deviceInfo;
            const deviceId = deviceInfo.deviceId;
+            deviceInfoByDeviceId.set(deviceId, deviceInfo);

            if (!contentMap[userId]) {
                contentMap[userId] = {};
@@ -636,7 +658,10 @@ class MegolmEncryption extends EncryptionAlgorithm {
                for (const userId of Object.keys(contentMap)) {
                    for (const deviceId of Object.keys(contentMap[userId])) {
                        session.markSharedWithDevice(
-                            userId, deviceId, chainIndex,
+                            userId,
+                            deviceId,
+                            deviceInfoByDeviceId.get(deviceId).getIdentityKey(),
+                            chainIndex,
                        );
                    }
                }
@@ -661,7 +686,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
        userDeviceMap: IOlmDevice<IBlockedDevice>[],
        payload: IPayload,
    ): Promise<void> {
-        const contentMap = {};
+        const contentMap: Record<string, Record<string, IPayload>> = {};

        for (const val of userDeviceMap) {
            const userId = val.userId;
@@ -685,7 +710,7 @@ class MegolmEncryption extends EncryptionAlgorithm {

        await this.baseApis.sendToDevice("org.matrix.room_key.withheld", contentMap);

-        // store that we successfully uploaded the keys of the current slice
+        // record the fact that we notified these blocked devices
        for (const userId of Object.keys(contentMap)) {
            for (const deviceId of Object.keys(contentMap[userId])) {
                session.markNotifiedBlockedDevice(userId, deviceId);
@@ -719,8 +744,8 @@ class MegolmEncryption extends EncryptionAlgorithm {
            logger.debug(`megolm session ${sessionId} never shared with user ${userId}`);
            return;
        }
-        const sentChainIndex = obSessionInfo.sharedWithDevices[userId][device.deviceId];
-        if (sentChainIndex === undefined) {
+        const sessionSharedData = obSessionInfo.sharedWithDevices[userId][device.deviceId];
+        if (sessionSharedData === undefined) {
            logger.debug(
                "megolm session ID " + sessionId + " never shared with device " +
                userId + ":" + device.deviceId,
@@ -728,10 +753,18 @@ class MegolmEncryption extends EncryptionAlgorithm {
            return;
        }

+        if (sessionSharedData.deviceKey !== device.getIdentityKey()) {
+            logger.warn(
+                `Session has been shared with device ${device.deviceId} but with identity ` +
+                `key ${sessionSharedData.deviceKey}. Key is now ${device.getIdentityKey()}!`,
+            );
+            return;
+        }
+
        // get the key from the inbound session: the outbound one will already
        // have been ratcheted to the next chain index.
        const key = await this.olmDevice.getInboundGroupSessionKey(
-            this.roomId, senderKey, sessionId, sentChainIndex,
+            this.roomId, senderKey, sessionId, sessionSharedData.messageIndex,
        );

        if (!key) {
@@ -826,9 +859,9 @@ class MegolmEncryption extends EncryptionAlgorithm {

        this.getDevicesWithoutSessions(devicemap, devicesByUser, errorDevices);

-        logger.debug(`Sharing keys with Olm sessions in ${this.roomId}`);
+        logger.debug(`Sharing keys with newly created Olm sessions in ${this.roomId}`);
        await this.shareKeyWithOlmSessions(session, key, payload, devicemap);
-        logger.debug(`Shared keys with Olm sessions in ${this.roomId}`);
+        logger.debug(`Shared keys with newly created Olm sessions in ${this.roomId}`);
    }

    private async shareKeyWithOlmSessions(
@@ -844,7 +877,8 @@ class MegolmEncryption extends EncryptionAlgorithm {
                `megolm keys for ${session.sessionId} ` +
                `in ${this.roomId} (slice ${i + 1}/${userDeviceMaps.length})`;
            try {
-                logger.debug(`Sharing ${taskDetail}`);
+                logger.debug(`Sharing ${taskDetail}`,
+                    userDeviceMaps[i].map((d) => `${d.userId}/${d.deviceInfo.deviceId}`));
                await this.encryptAndSendKeysToDevices(
                    session, key.chain_index, userDeviceMaps[i], payload,
                );
@@ -882,20 +916,20 @@ class MegolmEncryption extends EncryptionAlgorithm {
            const deviceId = deviceInfo.deviceId;

            session.markSharedWithDevice(
-                userId, deviceId, key.chain_index,
+                userId, deviceId, deviceInfo.getIdentityKey(), key.chain_index,
            );
        }

-        const filteredFailedDevices =
+        const unnotifiedFailedDevices =
            await this.olmDevice.filterOutNotifiedErrorDevices(
                failedDevices,
            );
        logger.debug(
-            `Filtered down to ${filteredFailedDevices.length} error devices ` +
-            `in ${this.roomId}`,
+            `Need to notify ${unnotifiedFailedDevices.length} failed devices ` +
+            `which haven't been notified before in ${this.roomId}`,
        );
        const blockedMap: Record<string, Record<string, { device: IBlockedDevice }>> = {};
-        for (const { userId, deviceInfo } of filteredFailedDevices) {
+        for (const { userId, deviceInfo } of unnotifiedFailedDevices) {
            blockedMap[userId] = blockedMap[userId] || {};
            // we use a similar format to what
            // olmlib.ensureOlmSessionsForDevices returns, so that
@@ -912,7 +946,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
        // send the notifications
        await this.notifyBlockedDevices(session, blockedMap);
        logger.debug(
-            `Notified ${filteredFailedDevices.length} devices we failed to ` +
+            `Notified ${unnotifiedFailedDevices.length} devices we failed to ` +
            `create Olm sessions in ${this.roomId}`,
        );
    }
@@ -1078,10 +1112,10 @@ class MegolmEncryption extends EncryptionAlgorithm {
     *   devices we should shared the session with.
     */
    private checkForUnknownDevices(devicesInRoom: DeviceInfoMap): void {
-        const unknownDevices = {};
+        const unknownDevices: Record<string, Record<string, DeviceInfo>> = {};

-        Object.keys(devicesInRoom).forEach((userId)=>{
-            Object.keys(devicesInRoom[userId]).forEach((deviceId)=>{
+        Object.keys(devicesInRoom).forEach((userId) => {
+            Object.keys(devicesInRoom[userId]).forEach((deviceId) => {
                const device = devicesInRoom[userId][deviceId];
                if (device.isUnverified() && !device.isKnown()) {
                    if (!unknownDevices[userId]) {
@@ -1277,8 +1311,7 @@ class MegolmDecryption extends DecryptionAlgorithm {
                content.sender_key, event.getTs() - 120000,
            );
            if (problem) {
-                let problemDescription = PROBLEM_DESCRIPTIONS[problem.type]
-                    || PROBLEM_DESCRIPTIONS.unknown;
+                let problemDescription = PROBLEM_DESCRIPTIONS[problem.type as "no_olm"] || PROBLEM_DESCRIPTIONS.unknown;
                if (problem.fixed) {
                    problemDescription +=
                        " Trying to create a new secure channel and re-requesting the keys.";
@@ -1372,14 +1405,14 @@ class MegolmDecryption extends DecryptionAlgorithm {
        const senderKey = content.sender_key;
        const sessionId = content.session_id;
        const senderPendingEvents = this.pendingEvents[senderKey];
-        const pendingEvents = senderPendingEvents && senderPendingEvents.get(sessionId);
+        const pendingEvents = senderPendingEvents?.get(sessionId);
        if (!pendingEvents) {
            return;
        }

        pendingEvents.delete(event);
        if (pendingEvents.size === 0) {
-            senderPendingEvents.delete(senderKey);
+            senderPendingEvents.delete(sessionId);
        }
        if (senderPendingEvents.size === 0) {
            delete this.pendingEvents[senderKey];
@@ -1391,7 +1424,7 @@ class MegolmDecryption extends DecryptionAlgorithm {
     *
     * @param {module:models/event.MatrixEvent} event key event
     */
-    public onRoomKeyEvent(event: MatrixEvent): void {
+    public onRoomKeyEvent(event: MatrixEvent): Promise<void> {
        const content = event.getContent();
        const sessionId = content.session_id;
        let senderKey = event.getSenderKey();
@@ -1733,7 +1766,7 @@ class MegolmDecryption extends DecryptionAlgorithm {
        }));

        // If decrypted successfully, they'll have been removed from pendingEvents
-        return !((this.pendingEvents[senderKey] || {})[sessionId]);
+        return !this.pendingEvents[senderKey]?.has(sessionId);
    }

    public async retryDecryptionFromSender(senderKey: string): Promise<boolean> {
@@ -1767,12 +1800,12 @@ class MegolmDecryption extends DecryptionAlgorithm {
        for (const [senderKey, sessionId] of sharedHistorySessions) {
            const payload = await this.buildKeyForwardingMessage(this.roomId, senderKey, sessionId);

-            const promises = [];
-            const contentMap = {};
+            const promises: Promise<unknown>[] = [];
+            const contentMap: Record<string, Record<string, IEncryptedContent>> = {};
            for (const [userId, devices] of Object.entries(devicesByUser)) {
                contentMap[userId] = {};
                for (const deviceInfo of devices) {
-                    const encryptedContent = {
+                    const encryptedContent: IEncryptedContent = {
                        algorithm: olmlib.OLM_ALGORITHM,
                        sender_key: this.olmDevice.deviceCurve25519Key,
                        ciphertext: {},
@@ -36,7 +36,7 @@ import { IEventDecryptionResult } from "../index";
 const DeviceVerification = DeviceInfo.DeviceVerification;

 interface IMessage {
-    type: number | string;
+    type: number;
    body: string;
 }

@@ -269,11 +269,11 @@ class OlmDecryption extends DecryptionAlgorithm {
            // not a prekey message: we can safely just try & decrypt it
            return this.reallyDecryptMessage(theirDeviceIdentityKey, message);
        } else {
-            const myPromise = this.olmDevice._olmPrekeyPromise.then(() => {
+            const myPromise = this.olmDevice.olmPrekeyPromise.then(() => {
                return this.reallyDecryptMessage(theirDeviceIdentityKey, message);
            });
            // we want the error, but don't propagate it to the next decryption
-            this.olmDevice._olmPrekeyPromise = myPromise.catch(() => {});
+            this.olmDevice.olmPrekeyPromise = myPromise.catch(() => {});
            return await myPromise;
        }
    }
@@ -282,7 +282,7 @@ class OlmDecryption extends DecryptionAlgorithm {
        const sessionIds = await this.olmDevice.getSessionIdsForDevice(theirDeviceIdentityKey);

        // try each session in turn.
-        const decryptionErrors = {};
+        const decryptionErrors: Record<string, string> = {};
        for (let i = 0; i < sessionIds.length; i++) {
            const sessionId = sessionIds[i];
            try {
@@ -58,16 +58,9 @@ export interface IEncryptedEventInfo {
 }

 export interface IRecoveryKey {
-    keyInfo: {
-        pubkey: string;
-        passphrase?: {
-            algorithm: string;
-            iterations: number;
-            salt: string;
-        };
-    };
+    keyInfo?: IAddSecretStorageKeyOpts;
    privateKey: Uint8Array;
-    encodedPrivateKey: string;
+    encodedPrivateKey?: string;
 }

 export interface ICreateSecretStorageOpts {
@@ -125,12 +118,13 @@ export interface IPassphraseInfo {
    algorithm: "m.pbkdf2";
    iterations: number;
    salt: string;
-    bits: number;
+    bits?: number;
 }

 export interface IAddSecretStorageKeyOpts {
-    name: string;
-    passphrase: IPassphraseInfo;
+    pubkey: string;
+    passphrase?: IPassphraseInfo;
+    name?: string;
    key: Uint8Array;
 }

@@ -142,7 +136,7 @@ export interface IImportOpts {
 }

 export interface IImportRoomKeysOpts {
-    progressCallback: (stage: IImportOpts) => void;
+    progressCallback?: (stage: IImportOpts) => void;
    untrusted?: boolean;
    source?: string; // TODO: Enum
 }
@@ -26,13 +26,13 @@ import { MEGOLM_ALGORITHM, verifySignature } from "./olmlib";
 import { DeviceInfo } from "./deviceinfo";
 import { DeviceTrustLevel } from './CrossSigning';
 import { keyFromPassphrase } from './key_passphrase';
-import { sleep } from "../utils";
+import { getCrypto, sleep } from "../utils";
 import { IndexedDBCryptoStore } from './store/indexeddb-crypto-store';
 import { encodeRecoveryKey } from './recoverykey';
-import { encryptAES, decryptAES, calculateKeyCheck } from './aes';
-import { getCrypto } from '../utils';
-import { ICurve25519AuthData, IAes256AuthData, IKeyBackupInfo, IKeyBackupSession } from "./keybackup";
+import { calculateKeyCheck, decryptAES, encryptAES } from './aes';
+import { IAes256AuthData, ICurve25519AuthData, IKeyBackupInfo, IKeyBackupSession } from "./keybackup";
 import { UnstableValue } from "../NamespacedValue";
+import { CryptoEvent, IMegolmSessionData } from "./index";

 const KEY_BACKUP_KEYS_PER_REQUEST = 200;

@@ -49,6 +49,8 @@ type SigInfo = {
 export type TrustInfo = {
    usable: boolean; // is the backup trusted, true iff there is a sig that is valid & from a trusted device
    sigs: SigInfo[];
+    // eslint-disable-next-line camelcase
+    trusted_locally?: boolean;
 };

 export interface IKeyBackupCheck {
@@ -85,7 +87,7 @@ interface BackupAlgorithmClass {
 interface BackupAlgorithm {
    untrusted: boolean;
    encryptSession(data: Record<string, any>): Promise<any>;
-    decryptSessions(ciphertexts: Record<string, IKeyBackupSession>): Promise<Record<string, any>[]>;
+    decryptSessions(ciphertexts: Record<string, IKeyBackupSession>): Promise<IMegolmSessionData[]>;
    authData: AuthData;
    keyMatches(key: ArrayLike<number>): Promise<boolean>;
    free(): void;
@@ -152,7 +154,7 @@ export class BackupManager {

        this.algorithm = await BackupManager.makeAlgorithm(info, this.getKey);

-        this.baseApis.emit('crypto.keyBackupStatus', true);
+        this.baseApis.emit(CryptoEvent.KeyBackupStatus, true);

        // There may be keys left over from a partially completed backup, so
        // schedule a send to check.
@@ -170,7 +172,7 @@ export class BackupManager {

        this.backupInfo = undefined;

-        this.baseApis.emit('crypto.keyBackupStatus', false);
+        this.baseApis.emit(CryptoEvent.KeyBackupStatus, false);
    }

    public getKeyBackupEnabled(): boolean | null {
@@ -183,7 +185,6 @@ export class BackupManager {
    public async prepareKeyBackupVersion(
        key?: string | Uint8Array | null,
        algorithm?: string | undefined,
-        // eslint-disable-next-line camelcase
    ): Promise<IPreparedKeyBackupVersion> {
        const Algorithm = algorithm ? algorithmsByName[algorithm] : DefaultAlgorithm;
        if (!Algorithm) {
@@ -298,7 +299,7 @@ export class BackupManager {
        const ret = {
            usable: false,
            trusted_locally: false,
-            sigs: [],
+            sigs: [] as SigInfo[],
        };

        if (
@@ -311,14 +312,27 @@ export class BackupManager {
            return ret;
        }

-        const trustedPubkey = this.baseApis.crypto.sessionStore.getLocalTrustedBackupPubKey();
+        const privKey = await this.baseApis.crypto.getSessionBackupPrivateKey();
+        if (privKey) {
+            let algorithm;
+            try {
+                algorithm = await BackupManager.makeAlgorithm(backupInfo, async () => privKey);

-        if ("public_key" in backupInfo.auth_data && backupInfo.auth_data.public_key === trustedPubkey) {
-            logger.info("Backup public key " + trustedPubkey + " is trusted locally");
-            ret.trusted_locally = true;
+                if (await algorithm.keyMatches(privKey)) {
+                    logger.info("Backup is trusted locally");
+                    ret.trusted_locally = true;
+                }
+            } catch {
+                // do nothing -- if we have an error, then we don't mark it as
+                // locally trusted
+            } finally {
+                if (algorithm) {
+                    algorithm.free();
+                }
+            }
        }

-        const mySigs = backupInfo.auth_data.signatures[this.baseApis.getUserId()] || [];
+        const mySigs = backupInfo.auth_data.signatures[this.baseApis.getUserId()] || {};

        for (const keyId of Object.keys(mySigs)) {
            const keyIdParts = keyId.split(':');
@@ -443,7 +457,7 @@ export class BackupManager {
                            await this.checkKeyBackup();
                            // Backup version has changed or this backup version
                            // has been deleted
-                            this.baseApis.crypto.emit("crypto.keyBackupFailed", err.data.errcode);
+                            this.baseApis.crypto.emit(CryptoEvent.KeyBackupFailed, err.data.errcode);
                            throw err;
                        }
                    }
@@ -465,14 +479,14 @@ export class BackupManager {
     * @param {integer} limit Maximum number of keys to back up
     * @returns {integer} Number of sessions backed up
     */
-    private async backupPendingKeys(limit: number): Promise<number> {
+    public async backupPendingKeys(limit: number): Promise<number> {
        const sessions = await this.baseApis.crypto.cryptoStore.getSessionsNeedingBackup(limit);
        if (!sessions.length) {
            return 0;
        }

        let remaining = await this.baseApis.crypto.cryptoStore.countSessionsNeedingBackup();
-        this.baseApis.crypto.emit("crypto.keyBackupSessionsRemaining", remaining);
+        this.baseApis.crypto.emit(CryptoEvent.KeyBackupSessionsRemaining, remaining);

        const rooms: IKeyBackup["rooms"] = {};
        for (const session of sessions) {
@@ -509,7 +523,7 @@ export class BackupManager {

        await this.baseApis.crypto.cryptoStore.unmarkSessionsNeedingBackup(sessions);
        remaining = await this.baseApis.crypto.cryptoStore.countSessionsNeedingBackup();
-        this.baseApis.crypto.emit("crypto.keyBackupSessionsRemaining", remaining);
+        this.baseApis.crypto.emit(CryptoEvent.KeyBackupSessionsRemaining, remaining);

        return sessions.length;
    }
@@ -565,7 +579,7 @@ export class BackupManager {
        );

        const remaining = await this.baseApis.crypto.cryptoStore.countSessionsNeedingBackup();
-        this.baseApis.emit("crypto.keyBackupSessionsRemaining", remaining);
+        this.baseApis.emit(CryptoEvent.KeyBackupSessionsRemaining, remaining);
        return remaining;
    }

@@ -643,9 +657,7 @@ export class Curve25519 implements BackupAlgorithm {
        return this.publicKey.encrypt(JSON.stringify(plainText));
    }

-    public async decryptSessions(
-        sessions: Record<string, IKeyBackupSession>,
-    ): Promise<Record<string, any>[]> {
+    public async decryptSessions(sessions: Record<string, IKeyBackupSession>): Promise<IMegolmSessionData[]> {
        const privKey = await this.getKey();
        const decryption = new global.Olm.PkDecryption();
        try {
@@ -656,7 +668,7 @@ export class Curve25519 implements BackupAlgorithm {
                throw { errcode: MatrixClient.RESTORE_BACKUP_ERROR_BAD_KEY };
            }

-            const keys = [];
+            const keys: IMegolmSessionData[] = [];

            for (const [sessionId, sessionData] of Object.entries(sessions)) {
                try {
@@ -775,8 +787,8 @@ export class Aes256 implements BackupAlgorithm {
        return await encryptAES(JSON.stringify(plainText), this.key, data.session_id);
    }

-    async decryptSessions(sessions: Record<string, IKeyBackupSession>): Promise<Record<string, any>[]> {
-        const keys = [];
+    async decryptSessions(sessions: Record<string, IKeyBackupSession>): Promise<IMegolmSessionData[]> {
+        const keys: IMegolmSessionData[] = [];

        for (const [sessionId, sessionData] of Object.entries(sessions)) {
            try {
@@ -14,15 +14,16 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

+import anotherjson from "another-json";
+
 import { decodeBase64, encodeBase64 } from './olmlib';
 import { IndexedDBCryptoStore } from '../crypto/store/indexeddb-crypto-store';
 import { decryptAES, encryptAES } from './aes';
-import anotherjson from "another-json";
 import { logger } from '../logger';
 import { ISecretStorageKeyInfo } from "./api";
-
-// FIXME: these types should eventually go in a different file
-type Signatures = Record<string, Record<string, string>>;
+import { Crypto } from "./index";
+import { Method } from "../http-api";
+import { ISignatures } from "../@types/signed";

 export interface IDehydratedDevice {
    device_id: string; // eslint-disable-line camelcase
@@ -41,13 +42,13 @@ export interface IDeviceKeys {
    device_id: string; // eslint-disable-line camelcase
    user_id: string; // eslint-disable-line camelcase
    keys: Record<string, string>;
-    signatures?: Signatures;
+    signatures?: ISignatures;
 }

 export interface IOneTimeKey {
    key: string;
    fallback?: boolean;
-    signatures?: Signatures;
+    signatures?: ISignatures;
 }

 export const DEHYDRATION_ALGORITHM = "org.matrix.msc2697.v1.olm.libolm_pickle";
@@ -60,7 +61,7 @@ export class DehydrationManager {
    private key: Uint8Array;
    private keyInfo: {[props: string]: any};
    private deviceDisplayName: string;
-    constructor(private crypto) {
+    constructor(private readonly crypto: Crypto) {
        this.getDehydrationKeyFromCache();
    }
    async getDehydrationKeyFromCache(): Promise<void> {
@@ -73,7 +74,7 @@ export class DehydrationManager {
                    async (result) => {
                        if (result) {
                            const { key, keyInfo, deviceDisplayName, time } = result;
-                            const pickleKey = Buffer.from(this.crypto.olmDevice._pickleKey);
+                            const pickleKey = Buffer.from(this.crypto.olmDevice.pickleKey);
                            const decrypted = await decryptAES(key, pickleKey, DEHYDRATION_ALGORITHM);
                            this.key = decodeBase64(decrypted);
                            this.keyInfo = keyInfo;
@@ -158,7 +159,7 @@ export class DehydrationManager {
            this.timeoutId = undefined;
        }
        try {
-            const pickleKey = Buffer.from(this.crypto.olmDevice._pickleKey);
+            const pickleKey = Buffer.from(this.crypto.olmDevice.pickleKey);

            // update the crypto store with the timestamp
            const key = await encryptAES(encodeBase64(this.key), pickleKey, DEHYDRATION_ALGORITHM);
@@ -205,9 +206,10 @@ export class DehydrationManager {
            }

            logger.log("Uploading account to server");
-            const dehydrateResult = await this.crypto.baseApis.http.authedRequest(
+            // eslint-disable-next-line camelcase
+            const dehydrateResult = await this.crypto.baseApis.http.authedRequest<{ device_id: string }>(
                undefined,
-                "PUT",
+                Method.Put,
                "/dehydrated_device",
                undefined,
                {
@@ -242,7 +244,7 @@ export class DehydrationManager {
            }

            logger.log("Preparing one-time keys");
-            const oneTimeKeys = {};
+            const oneTimeKeys: Record<string, IOneTimeKey> = {};
            for (const [keyId, key] of Object.entries(otks.curve25519)) {
                const k: IOneTimeKey = { key };
                const signature = account.sign(anotherjson.stringify(k));
@@ -270,7 +272,7 @@ export class DehydrationManager {
            logger.log("Uploading keys to server");
            await this.crypto.baseApis.http.authedRequest(
                undefined,
-                "POST",
+                Method.Post,
                "/keys/upload/" + encodeURI(deviceId),
                undefined,
                {
@@ -68,7 +68,7 @@ export class DeviceInfo {
     *
     * @return {module:crypto~DeviceInfo} new DeviceInfo
     */
-    public static fromStorage(obj: IDevice, deviceId: string): DeviceInfo {
+    public static fromStorage(obj: Partial<IDevice>, deviceId: string): DeviceInfo {
        const res = new DeviceInfo(deviceId);
        for (const prop in obj) {
            if (obj.hasOwnProperty(prop)) {
@@ -22,27 +22,36 @@ limitations under the License.
 */

 import anotherjson from "another-json";
-import { EventEmitter } from 'events';

-import { ReEmitter } from '../ReEmitter';
+import { TypedReEmitter } from '../ReEmitter';
 import { logger } from '../logger';
-import { OlmDevice } from "./OlmDevice";
+import { IExportedDevice, OlmDevice } from "./OlmDevice";
 import * as olmlib from "./olmlib";
 import { DeviceInfoMap, DeviceList } from "./DeviceList";
 import { DeviceInfo, IDevice } from "./deviceinfo";
+import type { DecryptionAlgorithm, EncryptionAlgorithm } from "./algorithms";
 import * as algorithms from "./algorithms";
 import { createCryptoStoreCacheCallbacks, CrossSigningInfo, DeviceTrustLevel, UserTrustLevel } from './CrossSigning';
 import { EncryptionSetupBuilder } from "./EncryptionSetup";
 import {
+    IAccountDataClient,
+    ISecretRequest,
    SECRET_STORAGE_ALGORITHM_V1_AES,
    SecretStorage,
-    SecretStorageKeyTuple,
-    ISecretRequest,
    SecretStorageKeyObject,
+    SecretStorageKeyTuple,
 } from './SecretStorage';
-import { IAddSecretStorageKeyOpts, ISecretStorageKeyInfo } from "./api";
+import {
+    IAddSecretStorageKeyOpts,
+    ICreateSecretStorageOpts,
+    IEncryptedEventInfo,
+    IImportRoomKeysOpts,
+    IRecoveryKey,
+    ISecretStorageKeyInfo,
+} from "./api";
 import { OutgoingRoomKeyRequestManager } from './OutgoingRoomKeyRequestManager';
 import { IndexedDBCryptoStore } from './store/indexeddb-crypto-store';
+import { VerificationBase } from "./verification/Base";
 import { ReciprocateQRCode, SCAN_QR_CODE_METHOD, SHOW_QR_CODE_METHOD } from './verification/QRCode';
 import { SAS as SASVerification } from './verification/SAS';
 import { keyFromPassphrase } from './key_passphrase';
@@ -52,20 +61,28 @@ import { InRoomChannel, InRoomRequests } from "./verification/request/InRoomChan
 import { ToDeviceChannel, ToDeviceRequests } from "./verification/request/ToDeviceChannel";
 import { IllegalMethod } from "./verification/IllegalMethod";
 import { KeySignatureUploadError } from "../errors";
-import { decryptAES, encryptAES, calculateKeyCheck } from './aes';
+import { calculateKeyCheck, decryptAES, encryptAES } from './aes';
 import { DehydrationManager, IDeviceKeys, IOneTimeKey } from './dehydration';
 import { BackupManager } from "./backup";
 import { IStore } from "../store";
-import { Room } from "../models/room";
-import { RoomMember } from "../models/room-member";
-import { MatrixEvent } from "../models/event";
-import { MatrixClient, IKeysUploadResponse, SessionStore, ISignedKey } from "../client";
-import type { EncryptionAlgorithm, DecryptionAlgorithm } from "./algorithms/base";
+import { Room, RoomEvent } from "../models/room";
+import { RoomMember, RoomMemberEvent } from "../models/room-member";
+import { EventStatus, IClearEvent, IEvent, MatrixEvent, MatrixEventEvent } from "../models/event";
+import {
+    ClientEvent,
+    ICrossSigningKey,
+    IKeysUploadResponse,
+    ISignedKey,
+    IUploadKeySignaturesResponse,
+    MatrixClient,
+    SessionStore,
+} from "../client";
 import type { IRoomEncryption, RoomList } from "./RoomList";
-import { IRecoveryKey, IEncryptedEventInfo } from "./api";
 import { IKeyBackupInfo } from "./keybackup";
 import { ISyncStateData } from "../sync";
 import { CryptoStore } from "./store/base";
+import { IVerificationChannel } from "./verification/request/Channel";
+import { TypedEventEmitter } from "../models/typed-event-emitter";

 const DeviceVerification = DeviceInfo.DeviceVerification;

@@ -84,12 +101,12 @@ const defaultVerificationMethods = {
 * verification method names
 */
 // legacy export identifier
-export enum verificationMethods {
-    RECIPROCATE_QR_CODE = ReciprocateQRCode.NAME,
-    SAS = SASVerification.NAME,
-}
+export const verificationMethods = {
+    RECIPROCATE_QR_CODE: ReciprocateQRCode.NAME,
+    SAS: SASVerification.NAME,
+};

-export type VerificationMethod = verificationMethods;
+export type VerificationMethod = keyof typeof verificationMethods | string;

 export function isCryptoAvailable(): boolean {
    return Boolean(global.Olm);
@@ -98,7 +115,7 @@ export function isCryptoAvailable(): boolean {
 const MIN_FORCE_SESSION_INTERVAL_MS = 60 * 60 * 1000;

 interface IInitOpts {
-    exportedOlmDevice?: any; // TODO types
+    exportedOlmDevice?: IExportedDevice;
    pickleKey?: string;
 }

@@ -107,17 +124,6 @@ export interface IBootstrapCrossSigningOpts {
    authUploadDeviceSigningKeys?(makeRequest: (authData: any) => {}): Promise<void>;
 }

-interface IBootstrapSecretStorageOpts {
-    keyBackupInfo?: any; // TODO types
-    setupNewKeyBackup?: boolean;
-    setupNewSecretStorage?: boolean;
-    createSecretStorageKey?(): Promise<{
-        keyInfo?: any; // TODO types
-        privateKey?: Uint8Array;
-    }>;
-    getKeyBackupPassphrase?(): Promise<Uint8Array | null>;
-}
-
 /* eslint-disable camelcase */
 interface IRoomKey {
    room_id: string;
@@ -130,13 +136,14 @@ export interface IRoomKeyRequestBody extends IRoomKey {
 }

 export interface IMegolmSessionData {
+    [key: string]: any; // extensible
    sender_key: string;
    forwarding_curve25519_key_chain: string[];
    sender_claimed_keys: Record<string, string>;
    room_id: string;
    session_id: string;
    session_key: string;
-    algorithm: string;
+    algorithm?: string;
    untrusted?: boolean;
 }
 /* eslint-enable camelcase */
@@ -181,18 +188,63 @@ interface ISignableObject {
 }

 export interface IEventDecryptionResult {
-    clearEvent: object;
+    clearEvent: IClearEvent;
+    forwardingCurve25519KeyChain?: string[];
    senderCurve25519Key?: string;
    claimedEd25519Key?: string;
-    forwardingCurve25519KeyChain?: string[];
    untrusted?: boolean;
 }

-export class Crypto extends EventEmitter {
+export interface IRequestsMap {
+    getRequest(event: MatrixEvent): VerificationRequest;
+    getRequestByChannel(channel: IVerificationChannel): VerificationRequest;
+    setRequest(event: MatrixEvent, request: VerificationRequest): void;
+    setRequestByChannel(channel: IVerificationChannel, request: VerificationRequest): void;
+}
+
+export enum CryptoEvent {
+    DeviceVerificationChanged = "deviceVerificationChanged",
+    UserTrustStatusChanged = "userTrustStatusChanged",
+    UserCrossSigningUpdated = "userCrossSigningUpdated",
+    RoomKeyRequest = "crypto.roomKeyRequest",
+    RoomKeyRequestCancellation = "crypto.roomKeyRequestCancellation",
+    KeyBackupStatus = "crypto.keyBackupStatus",
+    KeyBackupFailed = "crypto.keyBackupFailed",
+    KeyBackupSessionsRemaining = "crypto.keyBackupSessionsRemaining",
+    KeySignatureUploadFailure = "crypto.keySignatureUploadFailure",
+    VerificationRequest = "crypto.verification.request",
+    Warning = "crypto.warning",
+    WillUpdateDevices = "crypto.willUpdateDevices",
+    DevicesUpdated = "crypto.devicesUpdated",
+    KeysChanged = "crossSigning.keysChanged",
+}
+
+export type CryptoEventHandlerMap = {
+    [CryptoEvent.DeviceVerificationChanged]: (userId: string, deviceId: string, device: DeviceInfo) => void;
+    [CryptoEvent.UserTrustStatusChanged]: (userId: string, trustLevel: UserTrustLevel) => void;
+    [CryptoEvent.RoomKeyRequest]: (request: IncomingRoomKeyRequest) => void;
+    [CryptoEvent.RoomKeyRequestCancellation]: (request: IncomingRoomKeyRequestCancellation) => void;
+    [CryptoEvent.KeyBackupStatus]: (enabled: boolean) => void;
+    [CryptoEvent.KeyBackupFailed]: (errcode: string) => void;
+    [CryptoEvent.KeyBackupSessionsRemaining]: (remaining: number) => void;
+    [CryptoEvent.KeySignatureUploadFailure]: (
+        failures: IUploadKeySignaturesResponse["failures"],
+        source: "checkOwnCrossSigningTrust" | "afterCrossSigningLocalKeyChange" | "setDeviceVerification",
+        upload: (opts: { shouldEmit: boolean }) => Promise<void>
+    ) => void;
+    [CryptoEvent.VerificationRequest]: (request: VerificationRequest<any>) => void;
+    [CryptoEvent.Warning]: (type: string) => void;
+    [CryptoEvent.KeysChanged]: (data: {}) => void;
+    [CryptoEvent.WillUpdateDevices]: (users: string[], initialFetch: boolean) => void;
+    [CryptoEvent.DevicesUpdated]: (users: string[], initialFetch: boolean) => void;
+    [CryptoEvent.UserCrossSigningUpdated]: (userId: string) => void;
+};
+
+export class Crypto extends TypedEventEmitter<CryptoEvent, CryptoEventHandlerMap> {
    /**
     * @return {string} The version of Olm.
     */
-    static getOlmVersion(): string {
+    static getOlmVersion(): [number, number, number] {
        return OlmDevice.getOlmVersion();
    }

@@ -203,9 +255,9 @@ export class Crypto extends EventEmitter {
    public readonly dehydrationManager: DehydrationManager;
    public readonly secretStorage: SecretStorage;

-    private readonly reEmitter: ReEmitter;
-    private readonly verificationMethods: any; // TODO types
-    private readonly supportedAlgorithms: string[];
+    private readonly reEmitter: TypedReEmitter<CryptoEvent, CryptoEventHandlerMap>;
+    private readonly verificationMethods: Map<VerificationMethod, typeof VerificationBase>;
+    public readonly supportedAlgorithms: string[];
    private readonly outgoingRoomKeyRequestManager: OutgoingRoomKeyRequestManager;
    private readonly toDeviceVerificationRequests: ToDeviceRequests;
    public readonly inRoomVerificationRequests: InRoomRequests;
@@ -257,6 +309,7 @@ export class Crypto extends EventEmitter {

    private oneTimeKeyCount: number;
    private needsNewFallback: boolean;
+    private fallbackCleanup?: number; // setTimeout ID

    /**
     * Cryptography bits
@@ -291,15 +344,15 @@ export class Crypto extends EventEmitter {
    constructor(
        public readonly baseApis: MatrixClient,
        public readonly sessionStore: SessionStore,
-        private readonly userId: string,
+        public readonly userId: string,
        private readonly deviceId: string,
        private readonly clientStore: IStore,
        public readonly cryptoStore: CryptoStore,
        private readonly roomList: RoomList,
-        verificationMethods: any[], // TODO types
+        verificationMethods: Array<keyof typeof defaultVerificationMethods | typeof VerificationBase>,
    ) {
        super();
-        this.reEmitter = new ReEmitter(this);
+        this.reEmitter = new TypedReEmitter(this);

        if (verificationMethods) {
            this.verificationMethods = new Map();
@@ -308,20 +361,21 @@ export class Crypto extends EventEmitter {
                    if (defaultVerificationMethods[method]) {
                        this.verificationMethods.set(
                            method,
-                            defaultVerificationMethods[method],
+                            <typeof VerificationBase>defaultVerificationMethods[method],
                        );
                    }
-                } else if (method.NAME) {
+                } else if (method["NAME"]) {
                    this.verificationMethods.set(
-                        method.NAME,
-                        method,
+                        method["NAME"],
+                        method as typeof VerificationBase,
                    );
                } else {
                    logger.warn(`Excluding unknown verification method ${method}`);
                }
            }
        } else {
-            this.verificationMethods = defaultVerificationMethods;
+            this.verificationMethods =
+                new Map(Object.entries(defaultVerificationMethods)) as Map<VerificationMethod, typeof VerificationBase>;
        }

        this.backupManager = new BackupManager(baseApis, async () => {
@@ -359,8 +413,8 @@ export class Crypto extends EventEmitter {

        // XXX: This isn't removed at any point, but then none of the event listeners
        // this class sets seem to be removed at any point... :/
-        this.deviceList.on('userCrossSigningUpdated', this.onDeviceListUserCrossSigningUpdated);
-        this.reEmitter.reEmit(this.deviceList, ["crypto.devicesUpdated", "crypto.willUpdateDevices"]);
+        this.deviceList.on(CryptoEvent.UserCrossSigningUpdated, this.onDeviceListUserCrossSigningUpdated);
+        this.reEmitter.reEmit(this.deviceList, [CryptoEvent.DevicesUpdated, CryptoEvent.WillUpdateDevices]);

        this.supportedAlgorithms = Object.keys(algorithms.DECRYPTION_CLASSES);

@@ -376,7 +430,7 @@ export class Crypto extends EventEmitter {

        this.crossSigningInfo = new CrossSigningInfo(userId, cryptoCallbacks, cacheCallbacks);
        // Yes, we pass the client twice here: see SecretStorage
-        this.secretStorage = new SecretStorage(baseApis, cryptoCallbacks, baseApis);
+        this.secretStorage = new SecretStorage(baseApis as IAccountDataClient, cryptoCallbacks, baseApis);
        this.dehydrationManager = new DehydrationManager(this);

        // Assuming no app-supplied callback, default to getting from SSSS.
@@ -488,7 +542,7 @@ export class Crypto extends EventEmitter {
                    deviceTrust.isCrossSigningVerified()
                ) {
                    const deviceObj = this.deviceList.getStoredDevice(userId, deviceId);
-                    this.emit("deviceVerificationChanged", userId, deviceId, deviceObj);
+                    this.emit(CryptoEvent.DeviceVerificationChanged, userId, deviceId, deviceObj);
                }
            }
        }
@@ -504,7 +558,7 @@ export class Crypto extends EventEmitter {
     *     recovery key which should be disposed of after displaying to the user,
     *     and raw private key to avoid round tripping if needed.
     */
-    public async createRecoveryKeyFromPassphrase(password: string): Promise<IRecoveryKey> {
+    public async createRecoveryKeyFromPassphrase(password?: string): Promise<IRecoveryKey> {
        const decryption = new global.Olm.PkDecryption();
        try {
            const keyInfo: Partial<IRecoveryKey["keyInfo"]> = {};
@@ -760,12 +814,12 @@ export class Crypto extends EventEmitter {
     */
    // TODO this does not resolve with what it says it does
    public async bootstrapSecretStorage({
-        createSecretStorageKey = async () => ({ }),
+        createSecretStorageKey = async () => ({} as IRecoveryKey),
        keyBackupInfo,
        setupNewKeyBackup,
        setupNewSecretStorage,
        getKeyBackupPassphrase,
-    }: IBootstrapSecretStorageOpts = {}) {
+    }: ICreateSecretStorageOpts = {}) {
        logger.log("Bootstrapping Secure Secret Storage");
        const delegateCryptoCallbacks = this.baseApis.cryptoCallbacks;
        const builder = new EncryptionSetupBuilder(
@@ -781,8 +835,7 @@ export class Crypto extends EventEmitter {
        let newKeyId = null;

        // create a new SSSS key and set it as default
-        const createSSSS = async (opts, privateKey: Uint8Array) => {
-            opts = opts || {};
+        const createSSSS = async (opts: IAddSecretStorageKeyOpts, privateKey: Uint8Array) => {
            if (privateKey) {
                opts.key = privateKey;
            }
@@ -798,7 +851,7 @@ export class Crypto extends EventEmitter {
            return keyId;
        };

-        const ensureCanCheckPassphrase = async (keyId, keyInfo) => {
+        const ensureCanCheckPassphrase = async (keyId: string, keyInfo: ISecretStorageKeyInfo) => {
            if (!keyInfo.mac) {
                const key = await this.baseApis.cryptoCallbacks.getSecretStorageKey(
                    { keys: { [keyId]: keyInfo } }, "",
@@ -817,7 +870,7 @@ export class Crypto extends EventEmitter {
            }
        };

-        const signKeyBackupWithCrossSigning = async (keyBackupAuthData) => {
+        const signKeyBackupWithCrossSigning = async (keyBackupAuthData: IKeyBackupInfo["auth_data"]) => {
            if (
                this.crossSigningInfo.getId() &&
                await this.crossSigningInfo.isStoredInKeyCache("master")
@@ -878,7 +931,7 @@ export class Crypto extends EventEmitter {
            const backupKey = await this.getSessionBackupPrivateKey() || await getKeyBackupPassphrase();

            // create a new SSSS key and use the backup key as the new SSSS key
-            const opts: any = {}; // TODO types
+            const opts = {} as IAddSecretStorageKeyOpts;

            if (
                keyBackupInfo.auth_data.private_key_salt &&
@@ -896,9 +949,7 @@ export class Crypto extends EventEmitter {
            newKeyId = await createSSSS(opts, backupKey);

            // store the backup key in secret storage
-            await secretStorage.store(
-                "m.megolm_backup.v1", olmlib.encodeBase64(backupKey), [newKeyId],
-            );
+            await secretStorage.store("m.megolm_backup.v1", olmlib.encodeBase64(backupKey), [newKeyId]);

            // The backup is trusted because the user provided the private key.
            // Sign the backup with the cross-signing key so the key backup can
@@ -1028,7 +1079,7 @@ export class Crypto extends EventEmitter {
    public isSecretStored(
        name: string,
        checkKey?: boolean,
-    ): Promise<Record<string, ISecretStorageKeyInfo>> {
+    ): Promise<Record<string, ISecretStorageKeyInfo> | null> {
        return this.secretStorage.isStored(name, checkKey);
    }

@@ -1039,7 +1090,7 @@ export class Crypto extends EventEmitter {
        return this.secretStorage.request(name, devices);
    }

-    public getDefaultSecretStorageKeyId(): Promise<string> {
+    public getDefaultSecretStorageKeyId(): Promise<string | null> {
        return this.secretStorage.getDefaultKeyId();
    }

@@ -1097,7 +1148,7 @@ export class Crypto extends EventEmitter {
            await this.storeSessionBackupPrivateKey(key);
        }
        if (key && key.ciphertext) {
-            const pickleKey = Buffer.from(this.olmDevice._pickleKey);
+            const pickleKey = Buffer.from(this.olmDevice.pickleKey);
            const decrypted = await decryptAES(key, pickleKey, "m.megolm_backup.v1");
            key = olmlib.decodeBase64(decrypted);
        }
@@ -1113,7 +1164,7 @@ export class Crypto extends EventEmitter {
        if (!(key instanceof Uint8Array)) {
            throw new Error(`storeSessionBackupPrivateKey expects Uint8Array, got ${key}`);
        }
-        const pickleKey = Buffer.from(this.olmDevice._pickleKey);
+        const pickleKey = Buffer.from(this.olmDevice.pickleKey);
        const encryptedKey = await encryptAES(olmlib.encodeBase64(key), pickleKey, "m.megolm_backup.v1");
        return this.cryptoStore.doTxn(
            'readwrite',
@@ -1159,7 +1210,7 @@ export class Crypto extends EventEmitter {
        const signedDevice = await this.crossSigningInfo.signDevice(this.userId, device);
        logger.info(`Starting background key sig upload for ${this.deviceId}`);

-        const upload = ({ shouldEmit }) => {
+        const upload = ({ shouldEmit = false }) => {
            return this.baseApis.uploadKeySignatures({
                [this.userId]: {
                    [this.deviceId]: signedDevice,
@@ -1169,7 +1220,7 @@ export class Crypto extends EventEmitter {
                if (Object.keys(failures || []).length > 0) {
                    if (shouldEmit) {
                        this.baseApis.emit(
-                            "crypto.keySignatureUploadFailure",
+                            CryptoEvent.KeySignatureUploadFailure,
                            failures,
                            "afterCrossSigningLocalKeyChange",
                            upload, // continuation
@@ -1195,7 +1246,7 @@ export class Crypto extends EventEmitter {

            // Check all users for signatures if upgrade callback present
            // FIXME: do this in batches
-            const users = {};
+            const users: Record<string, IDeviceVerificationUpgrade> = {};
            for (const [userId, crossSigningInfo]
                of Object.entries(this.deviceList.crossSigningInfo)) {
                const upgradeInfo = await this.checkForDeviceVerificationUpgrade(
@@ -1272,7 +1323,7 @@ export class Crypto extends EventEmitter {
     */
    private async checkForValidDeviceSignature(
        userId: string,
-        key: any, // TODO types
+        key: ICrossSigningKey,
        devices: Record<string, IDevice>,
    ): Promise<string[]> {
        const deviceIds: string[] = [];
@@ -1395,11 +1446,10 @@ export class Crypto extends EventEmitter {
                // that reset the keys
                this.storeTrustedSelfKeys(null);
                // emit cross-signing has been disabled
-                this.emit("crossSigning.keysChanged", {});
+                this.emit(CryptoEvent.KeysChanged, {});
                // as the trust for our own user has changed,
                // also emit an event for this
-                this.emit("userTrustStatusChanged",
-                    this.userId, this.checkUserTrust(userId));
+                this.emit(CryptoEvent.UserTrustStatusChanged, this.userId, this.checkUserTrust(userId));
            }
        } else {
            await this.checkDeviceVerifications(userId);
@@ -1414,7 +1464,7 @@ export class Crypto extends EventEmitter {
                this.deviceList.setRawStoredCrossSigningForUser(userId, crossSigning.toStorage());
            }

-            this.emit("userTrustStatusChanged", userId, this.checkUserTrust(userId));
+            this.emit(CryptoEvent.UserTrustStatusChanged, userId, this.checkUserTrust(userId));
        }
    };

@@ -1493,7 +1543,7 @@ export class Crypto extends EventEmitter {
            !crossSigningPrivateKeys.has("user_signing")
        );

-        const keySignatures = {};
+        const keySignatures: Record<string, ISignedKey> = {};

        if (selfSigningChanged) {
            logger.info("Got new self-signing key", newCrossSigning.getId("self_signing"));
@@ -1548,7 +1598,7 @@ export class Crypto extends EventEmitter {
            // We may have existing signatures from deleted devices, which will cause
            // the entire upload to fail.
            keySignatures[this.crossSigningInfo.getId()] = Object.assign(
-                {},
+                {} as ISignedKey,
                masterKey,
                {
                    signatures: {
@@ -1562,7 +1612,7 @@ export class Crypto extends EventEmitter {

        const keysToUpload = Object.keys(keySignatures);
        if (keysToUpload.length) {
-            const upload = ({ shouldEmit }) => {
+            const upload = ({ shouldEmit = false }) => {
                logger.info(`Starting background key sig upload for ${keysToUpload}`);
                return this.baseApis.uploadKeySignatures({ [this.userId]: keySignatures })
                    .then((response) => {
@@ -1571,7 +1621,7 @@ export class Crypto extends EventEmitter {
                        if (Object.keys(failures || []).length > 0) {
                            if (shouldEmit) {
                                this.baseApis.emit(
-                                    "crypto.keySignatureUploadFailure",
+                                    CryptoEvent.KeySignatureUploadFailure,
                                    failures,
                                    "checkOwnCrossSigningTrust",
                                    upload,
@@ -1589,10 +1639,10 @@ export class Crypto extends EventEmitter {
            upload({ shouldEmit: true });
        }

-        this.emit("userTrustStatusChanged", userId, this.checkUserTrust(userId));
+        this.emit(CryptoEvent.UserTrustStatusChanged, userId, this.checkUserTrust(userId));

        if (masterChanged) {
-            this.baseApis.emit("crossSigning.keysChanged", {});
+            this.emit(CryptoEvent.KeysChanged, {});
            await this.afterCrossSigningLocalKeyChange();
        }

@@ -1607,7 +1657,7 @@ export class Crypto extends EventEmitter {
     *
     * @param {object} keys The new trusted set of keys
     */
-    private async storeTrustedSelfKeys(keys: any): Promise<void> { // TODO types
+    private async storeTrustedSelfKeys(keys: Record<string, ICrossSigningKey>): Promise<void> {
        if (keys) {
            this.crossSigningInfo.setKeys(keys);
        } else {
@@ -1679,18 +1729,14 @@ export class Crypto extends EventEmitter {
     * @param {external:EventEmitter} eventEmitter event source where we can register
     *    for event notifications
     */
-    public registerEventHandlers(eventEmitter: EventEmitter): void {
-        eventEmitter.on("RoomMember.membership", (event: MatrixEvent, member: RoomMember, oldMembership?: string) => {
-            try {
-                this.onRoomMembership(event, member, oldMembership);
-            } catch (e) {
-                logger.error("Error handling membership change:", e);
-            }
-        });
-
-        eventEmitter.on("toDeviceEvent", this.onToDeviceEvent);
-        eventEmitter.on("Room.timeline", this.onTimelineEvent);
-        eventEmitter.on("Event.decrypted", this.onTimelineEvent);
+    public registerEventHandlers(eventEmitter: TypedEventEmitter<
+        RoomMemberEvent.Membership | ClientEvent.ToDeviceEvent | RoomEvent.Timeline | MatrixEventEvent.Decrypted,
+        any
+    >): void {
+        eventEmitter.on(RoomMemberEvent.Membership, this.onMembership);
+        eventEmitter.on(ClientEvent.ToDeviceEvent, this.onToDeviceEvent);
+        eventEmitter.on(RoomEvent.Timeline, this.onTimelineEvent);
+        eventEmitter.on(MatrixEventEvent.Decrypted, this.onTimelineEvent);
    }

    /** Start background processes related to crypto */
@@ -1862,8 +1908,23 @@ export class Crypto extends EventEmitter {
                }

                if (this.getNeedsNewFallback()) {
-                    logger.info("generating fallback key");
-                    await this.olmDevice.generateFallbackKey();
+                    const fallbackKeys = await this.olmDevice.getFallbackKey();
+                    // if fallbackKeys is non-empty, we've already generated a
+                    // fallback key, but it hasn't been published yet, so we
+                    // can use that instead of generating a new one
+                    if (!fallbackKeys.curve25519 ||
+                        Object.keys(fallbackKeys.curve25519).length == 0) {
+                        logger.info("generating fallback key");
+                        if (this.fallbackCleanup) {
+                            // cancel any pending fallback cleanup because generating
+                            // a new fallback key will already drop the old fallback
+                            // that would have been dropped, and we don't want to kill
+                            // the current key
+                            clearTimeout(this.fallbackCleanup);
+                            delete this.fallbackCleanup;
+                        }
+                        await this.olmDevice.generateFallbackKey();
+                    }
                }

                logger.info("calling uploadOneTimeKeys");
@@ -1910,9 +1971,10 @@ export class Crypto extends EventEmitter {
    private async uploadOneTimeKeys() {
        const promises = [];

-        const fallbackJson: Record<string, IOneTimeKey> = {};
+        let fallbackJson: Record<string, IOneTimeKey>;
        if (this.getNeedsNewFallback()) {
-            const fallbackKeys = await this.olmDevice.getFallbackKey() as Record<string, Record<string, string>>;
+            fallbackJson = {};
+            const fallbackKeys = await this.olmDevice.getFallbackKey();
            for (const [keyId, key] of Object.entries(fallbackKeys.curve25519)) {
                const k = { key, fallback: true };
                fallbackJson["signed_curve25519:" + keyId] = k;
@@ -1922,7 +1984,7 @@ export class Crypto extends EventEmitter {
        }

        const oneTimeKeys = await this.olmDevice.getOneTimeKeys();
-        const oneTimeJson = {};
+        const oneTimeJson: Record<string, { key: string }> = {};

        for (const keyId in oneTimeKeys.curve25519) {
            if (oneTimeKeys.curve25519.hasOwnProperty(keyId)) {
@@ -1936,10 +1998,23 @@ export class Crypto extends EventEmitter {

        await Promise.all(promises);

-        const res = await this.baseApis.uploadKeysRequest({
+        const requestBody: Record<string, any> = {
            "one_time_keys": oneTimeJson,
-            "org.matrix.msc2732.fallback_keys": fallbackJson,
-        });
+        };
+
+        if (fallbackJson) {
+            requestBody["org.matrix.msc2732.fallback_keys"] = fallbackJson;
+            requestBody["fallback_keys"] = fallbackJson;
+        }
+
+        const res = await this.baseApis.uploadKeysRequest(requestBody);
+
+        if (fallbackJson) {
+            this.fallbackCleanup = setTimeout(() => {
+                delete this.fallbackCleanup;
+                this.olmDevice.forgetOldFallbackKey();
+            }, 60*60*1000);
+        }

        await this.olmDevice.markKeysAsPublished();
        return res;
@@ -2045,9 +2120,7 @@ export class Crypto extends EventEmitter {
            if (!this.crossSigningInfo.getId() && userId === this.crossSigningInfo.userId) {
                this.storeTrustedSelfKeys(xsk.keys);
                // This will cause our own user trust to change, so emit the event
-                this.emit(
-                    "userTrustStatusChanged", this.userId, this.checkUserTrust(userId),
-                );
+                this.emit(CryptoEvent.UserTrustStatusChanged, this.userId, this.checkUserTrust(userId));
            }

            // Now sign the master key with our user signing key (unless it's ourself)
@@ -2058,7 +2131,7 @@ export class Crypto extends EventEmitter {
                );
                const device = await this.crossSigningInfo.signUser(xsk);
                if (device) {
-                    const upload = async ({ shouldEmit }) => {
+                    const upload = async ({ shouldEmit = false }) => {
                        logger.info("Uploading signature for " + userId + "...");
                        const response = await this.baseApis.uploadKeySignatures({
                            [userId]: {
@@ -2069,7 +2142,7 @@ export class Crypto extends EventEmitter {
                        if (Object.keys(failures || []).length > 0) {
                            if (shouldEmit) {
                                this.baseApis.emit(
-                                    "crypto.keySignatureUploadFailure",
+                                    CryptoEvent.KeySignatureUploadFailure,
                                    failures,
                                    "setDeviceVerification",
                                    upload,
@@ -2131,7 +2204,7 @@ export class Crypto extends EventEmitter {
            logger.info("Own device " + deviceId + " marked verified: signing");

            // Signing only needed if other device not already signed
-            let device;
+            let device: ISignedKey;
            const deviceTrust = this.checkDeviceTrust(userId, deviceId);
            if (deviceTrust.isCrossSigningVerified()) {
                logger.log(`Own device ${deviceId} already cross-signing verified`);
@@ -2142,7 +2215,7 @@ export class Crypto extends EventEmitter {
            }

            if (device) {
-                const upload = async ({ shouldEmit }) => {
+                const upload = async ({ shouldEmit = false }) => {
                    logger.info("Uploading signature for " + deviceId);
                    const response = await this.baseApis.uploadKeySignatures({
                        [userId]: {
@@ -2153,7 +2226,7 @@ export class Crypto extends EventEmitter {
                    if (Object.keys(failures || []).length > 0) {
                        if (shouldEmit) {
                            this.baseApis.emit(
-                                "crypto.keySignatureUploadFailure",
+                                CryptoEvent.KeySignatureUploadFailure,
                                failures,
                                "setDeviceVerification",
                                upload, // continuation
@@ -2168,7 +2241,7 @@ export class Crypto extends EventEmitter {
        }

        const deviceObj = DeviceInfo.fromStorage(dev, deviceId);
-        this.emit("deviceVerificationChanged", userId, deviceId, deviceObj);
+        this.emit(CryptoEvent.DeviceVerificationChanged, userId, deviceId, deviceObj);
        return deviceObj;
    }

@@ -2176,24 +2249,20 @@ export class Crypto extends EventEmitter {
        return this.inRoomVerificationRequests.findRequestInProgress(roomId);
    }

-    public getVerificationRequestsToDeviceInProgress(userId: string): VerificationRequest {
+    public getVerificationRequestsToDeviceInProgress(userId: string): VerificationRequest[] {
        return this.toDeviceVerificationRequests.getRequestsInProgress(userId);
    }

-    public requestVerificationDM(userId: string, roomId: string): VerificationRequest {
+    public requestVerificationDM(userId: string, roomId: string): Promise<VerificationRequest> {
        const existingRequest = this.inRoomVerificationRequests.findRequestInProgress(roomId);
        if (existingRequest) {
            return Promise.resolve(existingRequest);
        }
        const channel = new InRoomChannel(this.baseApis, roomId, userId);
-        return this.requestVerificationWithChannel(
-            userId,
-            channel,
-            this.inRoomVerificationRequests,
-        );
+        return this.requestVerificationWithChannel(userId, channel, this.inRoomVerificationRequests);
    }

-    public requestVerification(userId: string, devices: string[]): VerificationRequest {
+    public requestVerification(userId: string, devices: string[]): Promise<VerificationRequest> {
        if (!devices) {
            devices = Object.keys(this.deviceList.getRawStoredDevicesForUser(userId));
        }
@@ -2202,18 +2271,14 @@ export class Crypto extends EventEmitter {
            return Promise.resolve(existingRequest);
        }
        const channel = new ToDeviceChannel(this.baseApis, userId, devices, ToDeviceChannel.makeTransactionId());
-        return this.requestVerificationWithChannel(
-            userId,
-            channel,
-            this.toDeviceVerificationRequests,
-        );
+        return this.requestVerificationWithChannel(userId, channel, this.toDeviceVerificationRequests);
    }

    private async requestVerificationWithChannel(
        userId: string,
-        channel: any, // TODO types
-        requestsMap: any, // TODO types
-    ): VerificationRequest {
+        channel: IVerificationChannel,
+        requestsMap: IRequestsMap,
+    ): Promise<VerificationRequest> {
        let request = new VerificationRequest(channel, this.verificationMethods, this.baseApis);
        // if transaction id is already known, add request
        if (channel.transactionId) {
@@ -2259,14 +2324,11 @@ export class Crypto extends EventEmitter {
        userId: string,
        deviceId: string,
        method: VerificationMethod,
-    ): VerificationRequest {
+    ): Promise<VerificationRequest> {
        const transactionId = ToDeviceChannel.makeTransactionId();
-        const channel = new ToDeviceChannel(
-            this.baseApis, userId, [deviceId], transactionId, deviceId);
-        const request = new VerificationRequest(
-            channel, this.verificationMethods, this.baseApis);
-        this.toDeviceVerificationRequests.setRequestBySenderAndTxnId(
-            userId, transactionId, request);
+        const channel = new ToDeviceChannel(this.baseApis, userId, [deviceId], transactionId, deviceId);
+        const request = new VerificationRequest(channel, this.verificationMethods, this.baseApis);
+        this.toDeviceVerificationRequests.setRequestBySenderAndTxnId(userId, transactionId, request);
        const verifier = request.beginKeyVerification(method, { userId, deviceId });
        // either reject by an error from verify() while sending .start
        // or resolve when the request receives the
@@ -2593,13 +2655,17 @@ export class Crypto extends EventEmitter {
     * the given users.
     *
     * @param {string[]} users list of user ids
+     * @param {boolean} force If true, force a new Olm session to be created. Default false.
     *
     * @return {Promise} resolves once the sessions are complete, to
     *    an Object mapping from userId to deviceId to
     *    {@link module:crypto~OlmSessionResult}
     */
-    ensureOlmSessionsForUsers(users: string[]): Promise<Record<string, Record<string, olmlib.IOlmSessionResult>>> {
-        const devicesByUser = {};
+    public ensureOlmSessionsForUsers(
+        users: string[],
+        force?: boolean,
+    ): Promise<Record<string, Record<string, olmlib.IOlmSessionResult>>> {
+        const devicesByUser: Record<string, DeviceInfo[]> = {};

        for (let i = 0; i < users.length; ++i) {
            const userId = users[i];
@@ -2623,7 +2689,7 @@ export class Crypto extends EventEmitter {
            }
        }

-        return olmlib.ensureOlmSessionsForDevices(this.olmDevice, this.baseApis, devicesByUser);
+        return olmlib.ensureOlmSessionsForDevices(this.olmDevice, this.baseApis, devicesByUser, force);
    }

    /**
@@ -2632,7 +2698,7 @@ export class Crypto extends EventEmitter {
     * @return {module:crypto/OlmDevice.MegolmSessionData[]} a list of session export objects
     */
    public async exportRoomKeys(): Promise<IMegolmSessionData[]> {
-        const exportedSessions = [];
+        const exportedSessions: IMegolmSessionData[] = [];
        await this.cryptoStore.doTxn(
            'readonly', [IndexedDBCryptoStore.STORE_INBOUND_GROUP_SESSIONS], (txn) => {
                this.cryptoStore.getAllEndToEndInboundGroupSessions(txn, (s) => {
@@ -2659,7 +2725,7 @@ export class Crypto extends EventEmitter {
     * @param {Function} opts.progressCallback called with an object which has a stage param
     * @return {Promise} a promise which resolves once the keys have been imported
     */
-    public importRoomKeys(keys: IMegolmSessionData[], opts: any = {}): Promise<any> { // TODO types
+    public importRoomKeys(keys: IMegolmSessionData[], opts: IImportRoomKeysOpts = {}): Promise<void> {
        let successes = 0;
        let failures = 0;
        const total = keys.length;
@@ -2686,7 +2752,7 @@ export class Crypto extends EventEmitter {
                successes++;
                if (opts.progressCallback) { updateProgress(); }
            });
-        }));
+        })).then();
    }

    /**
@@ -2710,7 +2776,6 @@ export class Crypto extends EventEmitter {
        }
    }

-    /* eslint-disable valid-jsdoc */    //https://github.com/eslint/eslint/issues/7307
    /**
     * Encrypt an event according to the configuration of the room.
     *
@@ -2721,8 +2786,6 @@ export class Crypto extends EventEmitter {
     * @return {Promise?} Promise which resolves when the event has been
     *     encrypted, or null if nothing was needed
     */
-    /* eslint-enable valid-jsdoc */
-    // TODO this return type lies
    public async encryptEvent(event: MatrixEvent, room: Room): Promise<void> {
        if (!room) {
            throw new Error("Cannot send encrypted messages in unknown rooms");
@@ -2757,12 +2820,21 @@ export class Crypto extends EventEmitter {
            delete content['m.relates_to'];
        }

-        const encryptedContent = await alg.encryptMessage(
-            room, event.getType(), content);
+        // Treat element's performance metrics the same as `m.relates_to` (when present)
+        const elementPerfMetrics = content['io.element.performance_metrics'];
+        if (elementPerfMetrics) {
+            content = Object.assign({}, content);
+            delete content['io.element.performance_metrics'];
+        }
+
+        const encryptedContent = await alg.encryptMessage(room, event.getType(), content);

        if (mRelatesTo) {
            encryptedContent['m.relates_to'] = mRelatesTo;
        }
+        if (elementPerfMetrics) {
+            encryptedContent['io.element.performance_metrics'] = elementPerfMetrics;
+        }

        event.makeEncrypted(
            "m.room.encrypted",
@@ -2792,7 +2864,7 @@ export class Crypto extends EventEmitter {
                    type: "m.room.message",
                    content: {},
                    unsigned: {
-                        redacted_because: decryptedEvent.clearEvent,
+                        redacted_because: decryptedEvent.clearEvent as IEvent,
                    },
                },
            };
@@ -3021,6 +3093,14 @@ export class Crypto extends EventEmitter {
        });
    }

+    private onMembership = (event: MatrixEvent, member: RoomMember, oldMembership?: string) => {
+        try {
+            this.onRoomMembership(event, member, oldMembership);
+        } catch (e) {
+            logger.error("Error handling membership change:", e);
+        }
+    };
+
    private onToDeviceEvent = (event: MatrixEvent): void => {
        try {
            logger.log(`received to_device ${event.getType()} from: ` +
@@ -3046,7 +3126,7 @@ export class Crypto extends EventEmitter {
                    event.attemptDecryption(this);
                }
                // once the event has been decrypted, try again
-                event.once('Event.decrypted', (ev) => {
+                event.once(MatrixEventEvent.Decrypted, (ev) => {
                    this.onToDeviceEvent(ev);
                });
            }
@@ -3125,7 +3205,7 @@ export class Crypto extends EventEmitter {
        if (!ToDeviceChannel.validateEvent(event, this.baseApis)) {
            return;
        }
-        const createRequest = event => {
+        const createRequest = (event: MatrixEvent) => {
            if (!ToDeviceChannel.canCreateRequest(ToDeviceChannel.getEventType(event))) {
                return;
            }
@@ -3143,11 +3223,7 @@ export class Crypto extends EventEmitter {
            return new VerificationRequest(
                channel, this.verificationMethods, this.baseApis);
        };
-        this.handleVerificationEvent(
-            event,
-            this.toDeviceVerificationRequests,
-            createRequest,
-        );
+        this.handleVerificationEvent(event, this.toDeviceVerificationRequests, createRequest);
    }

    /**
@@ -3170,7 +3246,7 @@ export class Crypto extends EventEmitter {
        if (!InRoomChannel.validateEvent(event, this.baseApis)) {
            return;
        }
-        const createRequest = event => {
+        const createRequest = (event: MatrixEvent) => {
            const channel = new InRoomChannel(
                this.baseApis,
                event.getRoomId(),
@@ -3178,20 +3254,38 @@ export class Crypto extends EventEmitter {
            return new VerificationRequest(
                channel, this.verificationMethods, this.baseApis);
        };
-        this.handleVerificationEvent(
-            event,
-            this.inRoomVerificationRequests,
-            createRequest,
-            liveEvent,
-        );
+        this.handleVerificationEvent(event, this.inRoomVerificationRequests, createRequest, liveEvent);
    };

    private async handleVerificationEvent(
        event: MatrixEvent,
-        requestsMap: any, // TODO types
-        createRequest: any, // TODO types
+        requestsMap: IRequestsMap,
+        createRequest: (event: MatrixEvent) => VerificationRequest,
        isLiveEvent = true,
    ): Promise<void> {
+        // Wait for event to get its final ID with pendingEventOrdering: "chronological", since DM channels depend on it.
+        if (event.isSending() && event.status != EventStatus.SENT) {
+            let eventIdListener;
+            let statusListener;
+            try {
+                await new Promise((resolve, reject) => {
+                    eventIdListener = resolve;
+                    statusListener = () => {
+                        if (event.status == EventStatus.CANCELLED) {
+                            reject(new Error("Event status set to CANCELLED."));
+                        }
+                    };
+                    event.once(MatrixEventEvent.LocalEventIdReplaced, eventIdListener);
+                    event.on(MatrixEventEvent.Status, statusListener);
+                });
+            } catch (err) {
+                logger.error("error while waiting for the verification event to be sent: " + err.message);
+                return;
+            } finally {
+                event.removeListener(MatrixEventEvent.LocalEventIdReplaced, eventIdListener);
+                event.removeListener(MatrixEventEvent.Status, statusListener);
+            }
+        }
        let request = requestsMap.getRequest(event);
        let isNewRequest = false;
        if (!request) {
@@ -3216,7 +3310,7 @@ export class Crypto extends EventEmitter {
            !request.invalid && // check it has enough events to pass the UNSENT stage
            !request.observeOnly;
        if (shouldEmit) {
-            this.baseApis.emit("crypto.verification.request", request);
+            this.baseApis.emit(CryptoEvent.VerificationRequest, request);
        }
    }

@@ -3280,7 +3374,7 @@ export class Crypto extends EventEmitter {
                return;
            }
        }
-        const devicesByUser = {};
+        const devicesByUser: Record<string, DeviceInfo[]> = {};
        devicesByUser[sender] = [device];
        await olmlib.ensureOlmSessionsForDevices(this.olmDevice, this.baseApis, devicesByUser, true);

@@ -3517,7 +3611,7 @@ export class Crypto extends EventEmitter {
            return;
        }

-        this.emit("crypto.roomKeyRequest", req);
+        this.emit(CryptoEvent.RoomKeyRequest, req);
    }

    /**
@@ -3536,7 +3630,7 @@ export class Crypto extends EventEmitter {
        // we should probably only notify the app of cancellations we told it
        // about, but we don't currently have a record of that, so we just pass
        // everything through.
-        this.emit("crypto.roomKeyRequestCancellation", cancellation);
+        this.emit(CryptoEvent.RoomKeyRequestCancellation, cancellation);
    }

    /**
@@ -15,6 +15,10 @@ limitations under the License.
 */

 import { randomString } from '../randomstring';
+import { getCrypto } from '../utils';
+
+const subtleCrypto = (typeof window !== "undefined" && window.crypto) ?
+    (window.crypto.subtle || window.crypto.webkitSubtle) : null;

 const DEFAULT_ITERATIONS = 500000;

@@ -70,11 +74,21 @@ export async function deriveKey(
    salt: string,
    iterations: number,
    numBits = DEFAULT_BITSIZE,
+): Promise<Uint8Array> {
+    return subtleCrypto
+        ? deriveKeyBrowser(password, salt, iterations, numBits)
+        : deriveKeyNode(password, salt, iterations, numBits);
+}
+
+async function deriveKeyBrowser(
+    password: string,
+    salt: string,
+    iterations: number,
+    numBits: number,
 ): Promise<Uint8Array> {
    const subtleCrypto = global.crypto.subtle;
    const TextEncoder = global.TextEncoder;
    if (!subtleCrypto || !TextEncoder) {
-        // TODO: Implement this for node
        throw new Error("Password-based backup is not avaiable on this platform");
    }

@@ -99,3 +113,17 @@ export async function deriveKey(

    return new Uint8Array(keybits);
 }
+
+async function deriveKeyNode(
+    password: string,
+    salt: string,
+    iterations: number,
+    numBits: number,
+): Promise<Uint8Array> {
+    const crypto = getCrypto();
+    if (!crypto) {
+        throw new Error("No usable crypto implementation");
+    }
+
+    return crypto.pbkdf2Sync(password, Buffer.from(salt, 'binary'), iterations, numBits, 'sha512');
+}
@@ -67,5 +67,5 @@ export interface IKeyBackupRestoreResult {

 export interface IKeyBackupRestoreOpts {
    cacheCompleteCallback?: () => void;
-    progressCallback?: ({ stage: string }) => void;
+    progressCallback?: (progress: { stage: string }) => void;
 }
@@ -21,15 +21,15 @@ limitations under the License.
 */

 import anotherjson from "another-json";
-import type { PkSigning } from "@matrix-org/olm";
 import { Logger } from "loglevel";

-import OlmDevice from "./OlmDevice";
+import type { PkSigning } from "@matrix-org/olm";
+import { OlmDevice } from "./OlmDevice";
 import { DeviceInfo } from "./deviceinfo";
 import { logger } from '../logger';
-import * as utils from "../utils";
 import { IOneTimeKey } from "./dehydration";
-import { MatrixClient } from "../client";
+import { IClaimOTKsResult, MatrixClient } from "../client";
+import { ISignatures } from "../@types/signed";

 enum Algorithm {
    Olm = "m.olm.v1.curve25519-aes-sha2",
@@ -126,13 +126,18 @@ export async function encryptMessageForDevice(
    // involved in the session. If we're looking to reduce data transfer in the
    // future, we could elide them for subsequent messages.

-    utils.extend(payload, payloadFields);
+    Object.assign(payload, payloadFields);

    resultsObject[deviceKey] = await olmDevice.encryptMessage(
        deviceKey, sessionId, JSON.stringify(payload),
    );
 }

+interface IExistingOlmSession {
+    device: DeviceInfo;
+    sessionId?: string;
+}
+
 /**
 * Get the existing olm sessions for the given devices, and the devices that
 * don't have olm sessions.
@@ -153,11 +158,11 @@ export async function getExistingOlmSessions(
    olmDevice: OlmDevice,
    baseApis: MatrixClient,
    devicesByUser: Record<string, DeviceInfo[]>,
-) {
-    const devicesWithoutSession = {};
-    const sessions = {};
+): Promise<[Record<string, DeviceInfo[]>, Record<string, Record<string, IExistingOlmSession>>]> {
+    const devicesWithoutSession: {[userId: string]: DeviceInfo[]} = {};
+    const sessions: {[userId: string]: {[deviceId: string]: IExistingOlmSession}} = {};

-    const promises = [];
+    const promises: Promise<void>[] = [];

    for (const [userId, devices] of Object.entries(devicesByUser)) {
        for (const deviceInfo of devices) {
@@ -231,10 +236,10 @@ export async function ensureOlmSessionsForDevices(
        force = false;
    }

-    const devicesWithoutSession = [
+    const devicesWithoutSession: [string, string][] = [
        // [userId, deviceId], ...
    ];
-    const result = {};
+    const result: {[userId: string]: {[deviceId: string]: IExistingOlmSession}} = {};
    const resolveSession: Record<string, (sessionId?: string) => void> = {};

    // Mark all sessions this task intends to update as in progress. It is
@@ -252,13 +257,13 @@ export async function ensureOlmSessionsForDevices(
                continue;
            }

-            if (!olmDevice._sessionsInProgress[key]) {
+            if (!olmDevice.sessionsInProgress[key]) {
                // pre-emptively mark the session as in-progress to avoid race
                // conditions.  If we find that we already have a session, then
                // we'll resolve
-                olmDevice._sessionsInProgress[key] = new Promise(resolve => {
+                olmDevice.sessionsInProgress[key] = new Promise(resolve => {
                    resolveSession[key] = (v: any) => {
-                        delete olmDevice._sessionsInProgress[key];
+                        delete olmDevice.sessionsInProgress[key];
                        resolve(v);
                    };
                });
@@ -291,9 +296,7 @@ export async function ensureOlmSessionsForDevices(
            }

            const forWhom = `for ${key} (${userId}:${deviceId})`;
-            const sessionId = await olmDevice.getSessionIdForDevice(
-                key, resolveSession[key], log,
-            );
+            const sessionId = await olmDevice.getSessionIdForDevice(key, !!resolveSession[key], log);
            if (sessionId !== null && resolveSession[key]) {
                // we found a session, but we had marked the session as
                // in-progress, so resolve it now, which will unmark it and
@@ -324,9 +327,7 @@ export async function ensureOlmSessionsForDevices(
    let taskDetail = `one-time keys for ${devicesWithoutSession.length} devices`;
    try {
        log.debug(`Claiming ${taskDetail}`);
-        res = await baseApis.claimOneTimeKeys(
-            devicesWithoutSession, oneTimeKeyAlgorithm, otkTimeout,
-        );
+        res = await baseApis.claimOneTimeKeys(devicesWithoutSession, oneTimeKeyAlgorithm, otkTimeout);
        log.debug(`Claimed ${taskDetail}`);
    } catch (e) {
        for (const resolver of Object.values(resolveSession)) {
@@ -340,8 +341,8 @@ export async function ensureOlmSessionsForDevices(
        failedServers.push(...Object.keys(res.failures));
    }

-    const otkResult = res.one_time_keys || {};
-    const promises = [];
+    const otkResult = res.one_time_keys || {} as IClaimOTKsResult["one_time_keys"];
+    const promises: Promise<void>[] = [];
    for (const [userId, devices] of Object.entries(devicesByUser)) {
        const userRes = otkResult[userId] || {};
        for (let j = 0; j < devices.length; j++) {
@@ -362,7 +363,7 @@ export async function ensureOlmSessionsForDevices(
            }

            const deviceRes = userRes[deviceId] || {};
-            let oneTimeKey = null;
+            let oneTimeKey: IOneTimeKey = null;
            for (const keyId in deviceRes) {
                if (keyId.indexOf(oneTimeKeyAlgorithm + ":") === 0) {
                    oneTimeKey = deviceRes[keyId];
@@ -444,7 +445,7 @@ async function _verifyKeyAndStartSession(

 export interface IObject {
    unsigned?: object;
-    signatures?: object;
+    signatures?: ISignatures;
 }

 /**
@@ -23,7 +23,7 @@ import { IRoomEncryption } from "../RoomList";
 import { IDevice } from "../deviceinfo";
 import { ICrossSigningInfo } from "../CrossSigning";
 import { PrefixedLogger } from "../../logger";
-import { InboundGroupSessionData } from "../../@types/partials";
+import { InboundGroupSessionData } from "../OlmDevice";
 import { IEncryptedPayload } from "../aes";

 /**
@@ -125,7 +125,7 @@ export interface CryptoStore {
    addSharedHistoryInboundGroupSession(roomId: string, senderKey: string, sessionId: string, txn?: unknown): void;
    getSharedHistoryInboundGroupSessions(
        roomId: string,
-        txn?: IDBTransaction,
+        txn?: unknown,
    ): Promise<[senderKey: string, sessionId: string][]>;

    // Session key backups
@@ -30,7 +30,7 @@ import { IRoomKeyRequestBody } from "../index";
 import { ICrossSigningKey } from "../../client";
 import { IOlmDevice } from "../algorithms/megolm";
 import { IRoomEncryption } from "../RoomList";
-import { InboundGroupSessionData } from "../../@types/partials";
+import { InboundGroupSessionData } from "../OlmDevice";
 import { IEncryptedPayload } from "../aes";

 export const VERSION = 10;
@@ -200,10 +200,10 @@ export class Backend implements CryptoStore {

        // index into the wantedStates array
        let stateIndex = 0;
-        let result;
+        let result: OutgoingRoomKeyRequest;

-        function onsuccess(ev) {
-            const cursor = ev.target.result;
+        function onsuccess(this: IDBRequest<IDBCursorWithValue>) {
+            const cursor = this.result;
            if (cursor) {
                // got a match
                result = cursor.value;
@@ -218,7 +218,7 @@ export class Backend implements CryptoStore {
            }

            const wantedState = wantedStates[stateIndex];
-            const cursorReq = ev.target.source.openCursor(wantedState);
+            const cursorReq = (this.source as IDBIndex).openCursor(wantedState);
            cursorReq.onsuccess = onsuccess;
        }

@@ -255,10 +255,10 @@ export class Backend implements CryptoStore {
        wantedStates: number[],
    ): Promise<OutgoingRoomKeyRequest[]> {
        let stateIndex = 0;
-        const results = [];
+        const results: OutgoingRoomKeyRequest[] = [];

-        function onsuccess(ev) {
-            const cursor = ev.target.result;
+        function onsuccess(this: IDBRequest<IDBCursorWithValue>) {
+            const cursor = this.result;
            if (cursor) {
                const keyReq = cursor.value;
                if (keyReq.recipients.includes({ userId, deviceId })) {
@@ -274,7 +274,7 @@ export class Backend implements CryptoStore {
                }

                const wantedState = wantedStates[stateIndex];
-                const cursorReq = ev.target.source.openCursor(wantedState);
+                const cursorReq = (this.source as IDBIndex).openCursor(wantedState);
                cursorReq.onsuccess = onsuccess;
            }
        }
@@ -306,10 +306,10 @@ export class Backend implements CryptoStore {
        expectedState: number,
        updates: Partial<OutgoingRoomKeyRequest>,
    ): Promise<OutgoingRoomKeyRequest | null> {
-        let result = null;
+        let result: OutgoingRoomKeyRequest = null;

-        function onsuccess(ev) {
-            const cursor = ev.target.result;
+        function onsuccess(this: IDBRequest<IDBCursorWithValue>) {
+            const cursor = this.result;
            if (!cursor) {
                return;
            }
@@ -444,7 +444,7 @@ export class Backend implements CryptoStore {
        const objectStore = txn.objectStore("sessions");
        const idx = objectStore.index("deviceKey");
        const getReq = idx.openCursor(deviceKey);
-        const results = {};
+        const results: Parameters<Parameters<Backend["getEndToEndSessions"]>[2]>[0] = {};
        getReq.onsuccess = function() {
            const cursor = getReq.result;
            if (cursor) {
@@ -734,7 +734,7 @@ export class Backend implements CryptoStore {
    }

    public getEndToEndRooms(txn: IDBTransaction, func: (rooms: Record<string, IRoomEncryption>) => void): void {
-        const rooms = {};
+        const rooms: Parameters<Parameters<Backend["getEndToEndRooms"]>[1]>[0] = {};
        const objectStore = txn.objectStore("rooms");
        const getReq = objectStore.openCursor();
        getReq.onsuccess = function() {
@@ -756,7 +756,7 @@ export class Backend implements CryptoStore {

    public getSessionsNeedingBackup(limit: number): Promise<ISession[]> {
        return new Promise((resolve, reject) => {
-            const sessions = [];
+            const sessions: ISession[] = [];

            const txn = this.db.transaction(
                ["sessions_needing_backup", "inbound_group_sessions"],
@@ -877,8 +877,8 @@ export class Backend implements CryptoStore {
        func: (txn: IDBTransaction) => T,
        log: PrefixedLogger = logger,
    ): Promise<T> {
-        let startTime;
-        let description;
+        let startTime: number;
+        let description: string;
        if (PROFILE_TRANSACTIONS) {
            const txnId = this.nextTxnId++;
            startTime = Date.now();
@@ -34,7 +34,7 @@ import { IRoomKeyRequestBody } from "../index";
 import { ICrossSigningKey } from "../../client";
 import { IOlmDevice } from "../algorithms/megolm";
 import { IRoomEncryption } from "../RoomList";
-import { InboundGroupSessionData } from "../../@types/partials";
+import { InboundGroupSessionData } from "../OlmDevice";
 import { IEncryptedPayload } from "../aes";

 /**
@@ -20,7 +20,7 @@ import { IDeviceData, IProblem, ISession, ISessionInfo, IWithheld, Mode } from "
 import { IOlmDevice } from "../algorithms/megolm";
 import { IRoomEncryption } from "../RoomList";
 import { ICrossSigningKey } from "../../client";
-import { InboundGroupSessionData } from "../../@types/partials";
+import { InboundGroupSessionData } from "../OlmDevice";
 import { IEncryptedPayload } from "../aes";

 /**
@@ -175,8 +175,10 @@ export class LocalStorageCryptoStore extends MemoryCryptoStore {
    }

    public async filterOutNotifiedErrorDevices(devices: IOlmDevice[]): Promise<IOlmDevice[]> {
-        const notifiedErrorDevices = getJsonItem<string[]>(this.store, KEY_NOTIFIED_ERROR_DEVICES) || {};
-        const ret = [];
+        const notifiedErrorDevices = getJsonItem<MemoryCryptoStore["notifiedErrorDevices"]>(
+            this.store, KEY_NOTIFIED_ERROR_DEVICES,
+        ) || {};
+        const ret: IOlmDevice[] = [];

        for (const device of devices) {
            const { userId, deviceInfo } = device;
@@ -291,7 +293,7 @@ export class LocalStorageCryptoStore extends MemoryCryptoStore {
    }

    public getEndToEndRooms(txn: unknown, func: (rooms: Record<string, IRoomEncryption>) => void): void {
-        const result = {};
+        const result: Record<string, IRoomEncryption> = {};
        const prefix = keyEndToEndRoomsPrefix('');

        for (let i = 0; i < this.store.length; ++i) {
@@ -306,7 +308,7 @@ export class LocalStorageCryptoStore extends MemoryCryptoStore {

    public getSessionsNeedingBackup(limit: number): Promise<ISession[]> {
        const sessionsNeedingBackup = getJsonItem<string[]>(this.store, KEY_SESSIONS_NEEDING_BACKUP) || {};
-        const sessions = [];
+        const sessions: ISession[] = [];

        for (const session in sessionsNeedingBackup) {
            if (Object.prototype.hasOwnProperty.call(sessionsNeedingBackup, session)) {
@@ -30,7 +30,7 @@ import { IRoomKeyRequestBody } from "../index";
 import { ICrossSigningKey } from "../../client";
 import { IOlmDevice } from "../algorithms/megolm";
 import { IRoomEncryption } from "../RoomList";
-import { InboundGroupSessionData } from "../../@types/partials";
+import { InboundGroupSessionData } from "../OlmDevice";
 import { IEncryptedPayload } from "../aes";

 /**
@@ -21,22 +21,48 @@ limitations under the License.
 */

 import { MatrixEvent } from '../../models/event';
-import { EventEmitter } from 'events';
 import { logger } from '../../logger';
 import { DeviceInfo } from '../deviceinfo';
 import { newTimeoutError } from "./Error";
-import { requestKeysDuringVerification } from "../CrossSigning";
+import { KeysDuringVerification, requestKeysDuringVerification } from "../CrossSigning";
+import { IVerificationChannel } from "./request/Channel";
+import { MatrixClient } from "../../client";
+import { VerificationRequest } from "./request/VerificationRequest";
+import { ListenerMap, TypedEventEmitter } from "../../models/typed-event-emitter";

 const timeoutException = new Error("Verification timed out");

 export class SwitchStartEventError extends Error {
-    constructor(startEvent) {
+    constructor(public readonly startEvent: MatrixEvent) {
        super();
-        this.startEvent = startEvent;
    }
 }

-export class VerificationBase extends EventEmitter {
+export type KeyVerifier = (keyId: string, device: DeviceInfo, keyInfo: string) => void;
+
+export enum VerificationEvent {
+    Cancel = "cancel",
+}
+
+export type VerificationEventHandlerMap = {
+    [VerificationEvent.Cancel]: (e: Error | MatrixEvent) => void;
+};
+
+export class VerificationBase<
+    Events extends string,
+    Arguments extends ListenerMap<Events | VerificationEvent>,
+> extends TypedEventEmitter<Events | VerificationEvent, Arguments, VerificationEventHandlerMap> {
+    private cancelled = false;
+    private _done = false;
+    private promise: Promise<void> = null;
+    private transactionTimeoutTimer: number = null;
+    protected expectedEvent: string;
+    private resolve: () => void;
+    private reject: (e: Error | MatrixEvent) => void;
+    private resolveEvent: (e: MatrixEvent) => void;
+    private rejectEvent: (e: Error) => void;
+    private started: boolean;
+
    /**
     * Base class for verification methods.
     *
@@ -64,22 +90,18 @@ export class VerificationBase extends EventEmitter {
     * @param {object} [request] the key verification request object related to
     * this verification, if any
     */
-    constructor(channel, baseApis, userId, deviceId, startEvent, request) {
+    constructor(
+        public readonly channel: IVerificationChannel,
+        public readonly baseApis: MatrixClient,
+        public readonly userId: string,
+        public readonly deviceId: string,
+        public startEvent: MatrixEvent,
+        public readonly request: VerificationRequest,
+    ) {
        super();
-        this._channel = channel;
-        this._baseApis = baseApis;
-        this.userId = userId;
-        this.deviceId = deviceId;
-        this.startEvent = startEvent;
-        this.request = request;
-
-        this.cancelled = false;
-        this._done = false;
-        this._promise = null;
-        this._transactionTimeoutTimer = null;
    }

-    get initiatedByMe() {
+    public get initiatedByMe(): boolean {
        // if there is no start event yet,
        // we probably want to send it,
        // which happens if we initiate
@@ -88,16 +110,20 @@ export class VerificationBase extends EventEmitter {
        }
        const sender = this.startEvent.getSender();
        const content = this.startEvent.getContent();
-        return sender === this._baseApis.getUserId() &&
-            content.from_device === this._baseApis.getDeviceId();
+        return sender === this.baseApis.getUserId() &&
+            content.from_device === this.baseApis.getDeviceId();
    }

-    _resetTimer() {
+    public get hasBeenCancelled(): boolean {
+        return this.cancelled;
+    }
+
+    private resetTimer(): void {
        logger.info("Refreshing/starting the verification transaction timeout timer");
-        if (this._transactionTimeoutTimer !== null) {
-            clearTimeout(this._transactionTimeoutTimer);
+        if (this.transactionTimeoutTimer !== null) {
+            clearTimeout(this.transactionTimeoutTimer);
        }
-        this._transactionTimeoutTimer = setTimeout(() => {
+        this.transactionTimeoutTimer = setTimeout(() => {
            if (!this._done && !this.cancelled) {
                logger.info("Triggering verification timeout");
                this.cancel(timeoutException);
@@ -105,18 +131,18 @@ export class VerificationBase extends EventEmitter {
        }, 10 * 60 * 1000); // 10 minutes
    }

-    _endTimer() {
-        if (this._transactionTimeoutTimer !== null) {
-            clearTimeout(this._transactionTimeoutTimer);
-            this._transactionTimeoutTimer = null;
+    private endTimer(): void {
+        if (this.transactionTimeoutTimer !== null) {
+            clearTimeout(this.transactionTimeoutTimer);
+            this.transactionTimeoutTimer = null;
        }
    }

-    _send(type, uncompletedContent) {
-        return this._channel.send(type, uncompletedContent);
+    protected send(type: string, uncompletedContent: Record<string, any>): Promise<void> {
+        return this.channel.send(type, uncompletedContent);
    }

-    _waitForEvent(type) {
+    protected waitForEvent(type: string): Promise<MatrixEvent> {
        if (this._done) {
            return Promise.reject(new Error("Verification is already done"));
        }
@@ -125,24 +151,24 @@ export class VerificationBase extends EventEmitter {
            return Promise.resolve(existingEvent);
        }

-        this._expectedEvent = type;
+        this.expectedEvent = type;
        return new Promise((resolve, reject) => {
-            this._resolveEvent = resolve;
-            this._rejectEvent = reject;
+            this.resolveEvent = resolve;
+            this.rejectEvent = reject;
        });
    }

-    canSwitchStartEvent() {
+    public canSwitchStartEvent(event: MatrixEvent): boolean {
        return false;
    }

-    switchStartEvent(event) {
+    public switchStartEvent(event: MatrixEvent): void {
        if (this.canSwitchStartEvent(event)) {
            logger.log("Verification Base: switching verification start event",
-                { restartingFlow: !!this._rejectEvent });
-            if (this._rejectEvent) {
-                const reject = this._rejectEvent;
-                this._rejectEvent = undefined;
+                { restartingFlow: !!this.rejectEvent });
+            if (this.rejectEvent) {
+                const reject = this.rejectEvent;
+                this.rejectEvent = undefined;
                reject(new SwitchStartEventError(event));
            } else {
                this.startEvent = event;
@@ -150,21 +176,21 @@ export class VerificationBase extends EventEmitter {
        }
    }

-    handleEvent(e) {
+    public handleEvent(e: MatrixEvent): void {
        if (this._done) {
            return;
-        } else if (e.getType() === this._expectedEvent) {
+        } else if (e.getType() === this.expectedEvent) {
            // if we receive an expected m.key.verification.done, then just
            // ignore it, since we don't need to do anything about it
-            if (this._expectedEvent !== "m.key.verification.done") {
-                this._expectedEvent = undefined;
-                this._rejectEvent = undefined;
-                this._resetTimer();
-                this._resolveEvent(e);
+            if (this.expectedEvent !== "m.key.verification.done") {
+                this.expectedEvent = undefined;
+                this.rejectEvent = undefined;
+                this.resetTimer();
+                this.resolveEvent(e);
            }
        } else if (e.getType() === "m.key.verification.cancel") {
-            const reject = this._reject;
-            this._reject = undefined;
+            const reject = this.reject;
+            this.reject = undefined;
            // there is only promise to reject if verify has been called
            if (reject) {
                const content = e.getContent();
@@ -172,36 +198,36 @@ export class VerificationBase extends EventEmitter {
                reject(new Error(`Other side cancelled verification ` +
                    `because ${reason} (${code})`));
            }
-        } else if (this._expectedEvent) {
+        } else if (this.expectedEvent) {
            // only cancel if there is an event expected.
            // if there is no event expected, it means verify() wasn't called
            // and we're just replaying the timeline events when syncing
            // after a refresh when the events haven't been stored in the cache yet.
            const exception = new Error(
-                "Unexpected message: expecting " + this._expectedEvent
+                "Unexpected message: expecting " + this.expectedEvent
                    + " but got " + e.getType(),
            );
-            this._expectedEvent = undefined;
-            if (this._rejectEvent) {
-                const reject = this._rejectEvent;
-                this._rejectEvent = undefined;
+            this.expectedEvent = undefined;
+            if (this.rejectEvent) {
+                const reject = this.rejectEvent;
+                this.rejectEvent = undefined;
                reject(exception);
            }
            this.cancel(exception);
        }
    }

-    done() {
-        this._endTimer(); // always kill the activity timer
+    public done(): Promise<KeysDuringVerification | void> {
+        this.endTimer(); // always kill the activity timer
        if (!this._done) {
            this.request.onVerifierFinished();
-            this._resolve();
-            return requestKeysDuringVerification(this._baseApis, this.userId, this.deviceId);
+            this.resolve();
+            return requestKeysDuringVerification(this.baseApis, this.userId, this.deviceId);
        }
    }

-    cancel(e) {
-        this._endTimer(); // always kill the activity timer
+    public cancel(e: Error | MatrixEvent): void {
+        this.endTimer(); // always kill the activity timer
        if (!this._done) {
            this.cancelled = true;
            this.request.onVerifierCancelled();
@@ -210,7 +236,7 @@ export class VerificationBase extends EventEmitter {
                // cancelled by the other user)
                if (e === timeoutException) {
                    const timeoutEvent = newTimeoutError();
-                    this._send(timeoutEvent.getType(), timeoutEvent.getContent());
+                    this.send(timeoutEvent.getType(), timeoutEvent.getContent());
                } else if (e instanceof MatrixEvent) {
                    const sender = e.getSender();
                    if (sender !== this.userId) {
@@ -219,33 +245,33 @@ export class VerificationBase extends EventEmitter {
                            content.code = content.code || "m.unknown";
                            content.reason = content.reason || content.body
                                || "Unknown reason";
-                            this._send("m.key.verification.cancel", content);
+                            this.send("m.key.verification.cancel", content);
                        } else {
-                            this._send("m.key.verification.cancel", {
+                            this.send("m.key.verification.cancel", {
                                code: "m.unknown",
                                reason: content.body || "Unknown reason",
                            });
                        }
                    }
                } else {
-                    this._send("m.key.verification.cancel", {
+                    this.send("m.key.verification.cancel", {
                        code: "m.unknown",
                        reason: e.toString(),
                    });
                }
            }
-            if (this._promise !== null) {
+            if (this.promise !== null) {
                // when we cancel without a promise, we end up with a promise
                // but no reject function. If cancel is called again, we'd error.
-                if (this._reject) this._reject(e);
+                if (this.reject) this.reject(e);
            } else {
                // FIXME: this causes an "Uncaught promise" console message
                // if nothing ends up chaining this promise.
-                this._promise = Promise.reject(e);
+                this.promise = Promise.reject(e);
            }
            // Also emit a 'cancel' event that the app can listen for to detect cancellation
            // before calling verify()
-            this.emit('cancel', e);
+            this.emit(VerificationEvent.Cancel, e);
        }
    }

@@ -255,31 +281,32 @@ export class VerificationBase extends EventEmitter {
     * @returns {Promise} Promise which resolves when the verification has
     *     completed.
     */
-    verify() {
-        if (this._promise) return this._promise;
+    public verify(): Promise<void> {
+        if (this.promise) return this.promise;

-        this._promise = new Promise((resolve, reject) => {
-            this._resolve = (...args) => {
+        this.promise = new Promise((resolve, reject) => {
+            this.resolve = (...args) => {
                this._done = true;
-                this._endTimer();
+                this.endTimer();
                resolve(...args);
            };
-            this._reject = (...args) => {
+            this.reject = (e: Error) => {
                this._done = true;
-                this._endTimer();
-                reject(...args);
+                this.endTimer();
+                reject(e);
            };
        });
-        if (this._doVerification && !this._started) {
-            this._started = true;
-            this._resetTimer(); // restart the timeout
-            Promise.resolve(this._doVerification())
-                .then(this.done.bind(this), this.cancel.bind(this));
+        if (this.doVerification && !this.started) {
+            this.started = true;
+            this.resetTimer(); // restart the timeout
+            Promise.resolve(this.doVerification()).then(this.done.bind(this), this.cancel.bind(this));
        }
-        return this._promise;
+        return this.promise;
    }

-    async _verifyKeys(userId, keys, verifier) {
+    protected doVerification?: () => Promise<void>;
+
+    protected async verifyKeys(userId: string, keys: Record<string, string>, verifier: KeyVerifier): Promise<void> {
        // we try to verify all the keys that we're told about, but we might
        // not know about all of them, so keep track of the keys that we know
        // about, and ignore the rest
@@ -287,15 +314,14 @@ export class VerificationBase extends EventEmitter {

        for (const [keyId, keyInfo] of Object.entries(keys)) {
            const deviceId = keyId.split(':', 2)[1];
-            const device = this._baseApis.getStoredDevice(userId, deviceId);
+            const device = this.baseApis.getStoredDevice(userId, deviceId);
            if (device) {
-                await verifier(keyId, device, keyInfo);
+                verifier(keyId, device, keyInfo);
                verifiedDevices.push(deviceId);
            } else {
-                const crossSigningInfo = this._baseApis.crypto.deviceList
-                      .getStoredCrossSigningForUser(userId);
+                const crossSigningInfo = this.baseApis.crypto.deviceList.getStoredCrossSigningForUser(userId);
                if (crossSigningInfo && crossSigningInfo.getId() === deviceId) {
-                    await verifier(keyId, DeviceInfo.fromStorage({
+                    verifier(keyId, DeviceInfo.fromStorage({
                        keys: {
                            [keyId]: deviceId,
                        },
@@ -323,7 +349,11 @@ export class VerificationBase extends EventEmitter {
        // to upload each signature in a separate API call which is silly because the
        // API supports as many signatures as you like.
        for (const deviceId of verifiedDevices) {
-            await this._baseApis.setDeviceVerified(userId, deviceId);
+            await this.baseApis.setDeviceVerified(userId, deviceId);
        }
    }
+
+    public get events(): string[] | undefined {
+        return undefined;
+    }
 }
@@ -1,5 +1,5 @@
 /*
-Copyright 2018 New Vector Ltd
+Copyright 2018 - 2021 The Matrix.org Foundation C.I.C.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -22,17 +22,17 @@ limitations under the License.

 import { MatrixEvent } from "../../models/event";

-export function newVerificationError(code, reason, extradata) {
-    const content = Object.assign({}, { code, reason }, extradata);
+export function newVerificationError(code: string, reason: string, extraData: Record<string, any>): MatrixEvent {
+    const content = Object.assign({}, { code, reason }, extraData);
    return new MatrixEvent({
        type: "m.key.verification.cancel",
        content,
    });
 }

-export function errorFactory(code, reason) {
-    return function(extradata) {
-        return newVerificationError(code, reason, extradata);
+export function errorFactory(code: string, reason: string): (extraData?: Record<string, any>) => MatrixEvent {
+    return function(extraData?: Record<string, any>) {
+        return newVerificationError(code, reason, extraData);
    };
 }

@@ -84,7 +84,7 @@ export const newInvalidMessageError = errorFactory(
    "m.invalid_message", "Invalid message",
 );

-export function errorFromEvent(event) {
+export function errorFromEvent(event: MatrixEvent): { code: string, reason: string } {
    const content = event.getContent();
    if (content) {
        const { code, reason } = content;
@@ -20,24 +20,36 @@ limitations under the License.
 * @module crypto/verification/IllegalMethod
 */

-import { VerificationBase as Base } from "./Base";
+import { VerificationBase as Base, VerificationEvent, VerificationEventHandlerMap } from "./Base";
+import { IVerificationChannel } from "./request/Channel";
+import { MatrixClient } from "../../client";
+import { MatrixEvent } from "../../models/event";
+import { VerificationRequest } from "./request/VerificationRequest";

 /**
 * @class crypto/verification/IllegalMethod/IllegalMethod
 * @extends {module:crypto/verification/Base}
 */
-export class IllegalMethod extends Base {
-    static factory(...args) {
-        return new IllegalMethod(...args);
+export class IllegalMethod extends Base<VerificationEvent, VerificationEventHandlerMap> {
+    public static factory(
+        channel: IVerificationChannel,
+        baseApis: MatrixClient,
+        userId: string,
+        deviceId: string,
+        startEvent: MatrixEvent,
+        request: VerificationRequest,
+    ): IllegalMethod {
+        return new IllegalMethod(channel, baseApis, userId, deviceId, startEvent, request);
    }

-    static get NAME() {
+    // eslint-disable-next-line @typescript-eslint/naming-convention
+    public static get NAME(): string {
        // Typically the name will be something else, but to complete
        // the contract we offer a default one here.
        return "org.matrix.illegal_method";
    }

-    async _doVerification() {
+    protected doVerification = async (): Promise<void> => {
        throw new Error("Verification is not possible with this method");
-    }
+    };
 }
@@ -1,6 +1,5 @@
 /*
-Copyright 2018 New Vector Ltd
-Copyright 2020 The Matrix.org Foundation C.I.C.
+Copyright 2018 - 2021 The Matrix.org Foundation C.I.C.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -20,31 +19,55 @@ limitations under the License.
 * @module crypto/verification/QRCode
 */

-import { VerificationBase as Base } from "./Base";
-import {
-    newKeyMismatchError,
-    newUserCancelledError,
-} from './Error';
-import { encodeUnpaddedBase64, decodeBase64 } from "../olmlib";
+import { VerificationBase as Base, VerificationEventHandlerMap } from "./Base";
+import { newKeyMismatchError, newUserCancelledError } from './Error';
+import { decodeBase64, encodeUnpaddedBase64 } from "../olmlib";
 import { logger } from '../../logger';
+import { VerificationRequest } from "./request/VerificationRequest";
+import { MatrixClient } from "../../client";
+import { IVerificationChannel } from "./request/Channel";
+import { MatrixEvent } from "../../models/event";

 export const SHOW_QR_CODE_METHOD = "m.qr_code.show.v1";
 export const SCAN_QR_CODE_METHOD = "m.qr_code.scan.v1";

+interface IReciprocateQr {
+    confirm(): void;
+    cancel(): void;
+}
+
+export enum QrCodeEvent {
+    ShowReciprocateQr = "show_reciprocate_qr",
+}
+
+type EventHandlerMap = {
+    [QrCodeEvent.ShowReciprocateQr]: (qr: IReciprocateQr) => void;
+} & VerificationEventHandlerMap;
+
 /**
 * @class crypto/verification/QRCode/ReciprocateQRCode
 * @extends {module:crypto/verification/Base}
 */
-export class ReciprocateQRCode extends Base {
-    static factory(...args) {
-        return new ReciprocateQRCode(...args);
+export class ReciprocateQRCode extends Base<QrCodeEvent, EventHandlerMap> {
+    public reciprocateQREvent: IReciprocateQr;
+
+    public static factory(
+        channel: IVerificationChannel,
+        baseApis: MatrixClient,
+        userId: string,
+        deviceId: string,
+        startEvent: MatrixEvent,
+        request: VerificationRequest,
+    ): ReciprocateQRCode {
+        return new ReciprocateQRCode(channel, baseApis, userId, deviceId, startEvent, request);
    }

-    static get NAME() {
+    // eslint-disable-next-line @typescript-eslint/naming-convention
+    public static get NAME(): string {
        return "m.reciprocate.v1";
    }

-    async _doVerification() {
+    protected doVerification = async (): Promise<void> => {
        if (!this.startEvent) {
            // TODO: Support scanning QR codes
            throw new Error("It is not currently possible to start verification" +
@@ -58,30 +81,30 @@ export class ReciprocateQRCode extends Base {
        }

        // 2. ask if other user shows shield as well
-        await new Promise((resolve, reject) => {
+        await new Promise<void>((resolve, reject) => {
            this.reciprocateQREvent = {
                confirm: resolve,
                cancel: () => reject(newUserCancelledError()),
            };
-            this.emit("show_reciprocate_qr", this.reciprocateQREvent);
+            this.emit(QrCodeEvent.ShowReciprocateQr, this.reciprocateQREvent);
        });

        // 3. determine key to sign / mark as trusted
-        const keys = {};
+        const keys: Record<string, string> = {};

        switch (qrCodeData.mode) {
-            case MODE_VERIFY_OTHER_USER: {
+            case Mode.VerifyOtherUser: {
                // add master key to keys to be signed, only if we're not doing self-verification
                const masterKey = qrCodeData.otherUserMasterKey;
                keys[`ed25519:${masterKey}`] = masterKey;
                break;
            }
-            case MODE_VERIFY_SELF_TRUSTED: {
+            case Mode.VerifySelfTrusted: {
                const deviceId = this.request.targetDevice.deviceId;
                keys[`ed25519:${deviceId}`] = qrCodeData.otherDeviceKey;
                break;
            }
-            case MODE_VERIFY_SELF_UNTRUSTED: {
+            case Mode.VerifySelfUntrusted: {
                const masterKey = qrCodeData.myMasterKey;
                keys[`ed25519:${masterKey}`] = masterKey;
                break;
@@ -89,7 +112,7 @@ export class ReciprocateQRCode extends Base {
        }

        // 4. sign the key (or mark own MSK as verified in case of MODE_VERIFY_SELF_TRUSTED)
-        await this._verifyKeys(this.userId, keys, (keyId, device, keyInfo) => {
+        await this.verifyKeys(this.userId, keys, (keyId, device, keyInfo) => {
            // make sure the device has the expected keys
            const targetKey = keys[keyId];
            if (!targetKey) throw newKeyMismatchError();
@@ -108,103 +131,88 @@ export class ReciprocateQRCode extends Base {
                }
            }
        });
-    }
+    };
 }

 const CODE_VERSION = 0x02; // the version of binary QR codes we support
 const BINARY_PREFIX = "MATRIX"; // ASCII, used to prefix the binary format
-const MODE_VERIFY_OTHER_USER = 0x00; // Verifying someone who isn't us
-const MODE_VERIFY_SELF_TRUSTED = 0x01; // We trust the master key
-const MODE_VERIFY_SELF_UNTRUSTED = 0x02; // We do not trust the master key
+
+enum Mode {
+    VerifyOtherUser = 0x00, // Verifying someone who isn't us
+    VerifySelfTrusted = 0x01, // We trust the master key
+    VerifySelfUntrusted = 0x02, // We do not trust the master key
+}
+
+interface IQrData {
+    prefix: string;
+    version: number;
+    mode: Mode;
+    transactionId: string;
+    firstKeyB64: string;
+    secondKeyB64: string;
+    secretB64: string;
+}

 export class QRCodeData {
    constructor(
-        mode, sharedSecret, otherUserMasterKey,
-        otherDeviceKey, myMasterKey, buffer,
-    ) {
-        this._sharedSecret = sharedSecret;
-        this._mode = mode;
-        this._otherUserMasterKey = otherUserMasterKey;
-        this._otherDeviceKey = otherDeviceKey;
-        this._myMasterKey = myMasterKey;
-        this._buffer = buffer;
-    }
+        public readonly mode: Mode,
+        private readonly sharedSecret: string,
+        // only set when mode is MODE_VERIFY_OTHER_USER, master key of other party at time of generating QR code
+        public readonly otherUserMasterKey: string | undefined,
+        // only set when mode is MODE_VERIFY_SELF_TRUSTED, device key of other party at time of generating QR code
+        public readonly otherDeviceKey: string | undefined,
+        // only set when mode is MODE_VERIFY_SELF_UNTRUSTED, own master key at time of generating QR code
+        public readonly myMasterKey: string | undefined,
+        private readonly buffer: Buffer,
+    ) {}

-    static async create(request, client) {
-        const sharedSecret = QRCodeData._generateSharedSecret();
-        const mode = QRCodeData._determineMode(request, client);
+    public static async create(request: VerificationRequest, client: MatrixClient): Promise<QRCodeData> {
+        const sharedSecret = QRCodeData.generateSharedSecret();
+        const mode = QRCodeData.determineMode(request, client);
        let otherUserMasterKey = null;
        let otherDeviceKey = null;
        let myMasterKey = null;
-        if (mode === MODE_VERIFY_OTHER_USER) {
+        if (mode === Mode.VerifyOtherUser) {
            const otherUserCrossSigningInfo =
                client.getStoredCrossSigningForUser(request.otherUserId);
            otherUserMasterKey = otherUserCrossSigningInfo.getId("master");
-        } else if (mode === MODE_VERIFY_SELF_TRUSTED) {
-            otherDeviceKey = await QRCodeData._getOtherDeviceKey(request, client);
-        } else if (mode === MODE_VERIFY_SELF_UNTRUSTED) {
+        } else if (mode === Mode.VerifySelfTrusted) {
+            otherDeviceKey = await QRCodeData.getOtherDeviceKey(request, client);
+        } else if (mode === Mode.VerifySelfUntrusted) {
            const myUserId = client.getUserId();
            const myCrossSigningInfo = client.getStoredCrossSigningForUser(myUserId);
            myMasterKey = myCrossSigningInfo.getId("master");
        }
-        const qrData = QRCodeData._generateQrData(
+        const qrData = QRCodeData.generateQrData(
            request, client, mode,
            sharedSecret,
            otherUserMasterKey,
            otherDeviceKey,
            myMasterKey,
        );
-        const buffer = QRCodeData._generateBuffer(qrData);
+        const buffer = QRCodeData.generateBuffer(qrData);
        return new QRCodeData(mode, sharedSecret,
            otherUserMasterKey, otherDeviceKey, myMasterKey, buffer);
    }

-    get buffer() {
-        return this._buffer;
-    }
-
-    get mode() {
-        return this._mode;
-    }
-
-    /**
-     * only set when mode is MODE_VERIFY_SELF_TRUSTED
-     * @return {string} device key of other party at time of generating QR code
-     */
-    get otherDeviceKey() {
-        return this._otherDeviceKey;
-    }
-
-    /**
-     * only set when mode is MODE_VERIFY_OTHER_USER
-     * @return {string} master key of other party at time of generating QR code
-     */
-    get otherUserMasterKey() {
-        return this._otherUserMasterKey;
-    }
-
-    /**
-     * only set when mode is MODE_VERIFY_SELF_UNTRUSTED
-     * @return {string} own master key at time of generating QR code
-     */
-    get myMasterKey() {
-        return this._myMasterKey;
-    }
-
    /**
     * The unpadded base64 encoded shared secret.
     */
-    get encodedSharedSecret() {
-        return this._sharedSecret;
+    public get encodedSharedSecret(): string {
+        return this.sharedSecret;
    }

-    static _generateSharedSecret() {
+    public getBuffer(): Buffer {
+        return this.buffer;
+    }
+
+    private static generateSharedSecret(): string {
        const secretBytes = new Uint8Array(11);
        global.crypto.getRandomValues(secretBytes);
        return encodeUnpaddedBase64(secretBytes);
    }

-    static async _getOtherDeviceKey(request, client) {
+    private static async getOtherDeviceKey(request: VerificationRequest, client: MatrixClient): Promise<string> {
        const myUserId = client.getUserId();
        const otherDevice = request.targetDevice;
        const otherDeviceId = otherDevice ? otherDevice.deviceId : null;
@@ -212,31 +220,35 @@ export class QRCodeData {
        if (!device) {
            throw new Error("could not find device " + otherDeviceId);
        }
-        const key = device.getFingerprint();
-        return key;
+        return device.getFingerprint();
    }

-    static _determineMode(request, client) {
+    private static determineMode(request: VerificationRequest, client: MatrixClient): Mode {
        const myUserId = client.getUserId();
        const otherUserId = request.otherUserId;

-        let mode = MODE_VERIFY_OTHER_USER;
+        let mode = Mode.VerifyOtherUser;
        if (myUserId === otherUserId) {
            // Mode changes depending on whether or not we trust the master cross signing key
            const myTrust = client.checkUserTrust(myUserId);
            if (myTrust.isCrossSigningVerified()) {
-                mode = MODE_VERIFY_SELF_TRUSTED;
+                mode = Mode.VerifySelfTrusted;
            } else {
-                mode = MODE_VERIFY_SELF_UNTRUSTED;
+                mode = Mode.VerifySelfUntrusted;
            }
        }
        return mode;
    }

-    static _generateQrData(request, client, mode,
-        encodedSharedSecret, otherUserMasterKey,
-        otherDeviceKey, myMasterKey,
-    ) {
+    private static generateQrData(
+        request: VerificationRequest,
+        client: MatrixClient,
+        mode: Mode,
+        encodedSharedSecret: string,
+        otherUserMasterKey: string,
+        otherDeviceKey: string,
+        myMasterKey: string,
+    ): IQrData {
        const myUserId = client.getUserId();
        const transactionId = request.channel.transactionId;
        const qrData = {
@@ -251,16 +263,16 @@ export class QRCodeData {

        const myCrossSigningInfo = client.getStoredCrossSigningForUser(myUserId);

-        if (mode === MODE_VERIFY_OTHER_USER) {
+        if (mode === Mode.VerifyOtherUser) {
            // First key is our master cross signing key
            qrData.firstKeyB64 = myCrossSigningInfo.getId("master");
            // Second key is the other user's master cross signing key
            qrData.secondKeyB64 = otherUserMasterKey;
-        } else if (mode === MODE_VERIFY_SELF_TRUSTED) {
+        } else if (mode === Mode.VerifySelfTrusted) {
            // First key is our master cross signing key
            qrData.firstKeyB64 = myCrossSigningInfo.getId("master");
            qrData.secondKeyB64 = otherDeviceKey;
-        } else if (mode === MODE_VERIFY_SELF_UNTRUSTED) {
+        } else if (mode === Mode.VerifySelfUntrusted) {
            // First key is our device's key
            qrData.firstKeyB64 = client.getDeviceEd25519Key();
            // Second key is what we think our master cross signing key is
@@ -269,7 +281,7 @@ export class QRCodeData {
        return qrData;
    }

-    static _generateBuffer(qrData) {
+    private static generateBuffer(qrData: IQrData): Buffer {
        let buf = Buffer.alloc(0); // we'll concat our way through life

        const appendByte = (b) => {
@@ -1,5 +1,5 @@
 /*
-Copyright 2018 New Vector Ltd
+Copyright 2018 - 2021 The Matrix.org Foundation C.I.C.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -19,8 +19,10 @@ limitations under the License.
 * @module crypto/verification/SAS
 */

-import { VerificationBase as Base, SwitchStartEventError } from "./Base";
 import anotherjson from 'another-json';
+import { Utility, SAS as OlmSAS } from "@matrix-org/olm";
+
+import { VerificationBase as Base, SwitchStartEventError, VerificationEventHandlerMap } from "./Base";
 import {
    errorFactory,
    newInvalidMessageError,
@@ -29,6 +31,7 @@ import {
    newUserCancelledError,
 } from './Error';
 import { logger } from '../../logger';
+import { IContent, MatrixEvent } from "../../models/event";

 const START_TYPE = "m.key.verification.start";

@@ -38,7 +41,7 @@ const EVENTS = [
    "m.key.verification.mac",
 ];

-let olmutil;
+let olmutil: Utility;

 const newMismatchedSASError = errorFactory(
    "m.mismatched_sas", "Mismatched short authentication string",
@@ -48,7 +51,7 @@ const newMismatchedCommitmentError = errorFactory(
    "m.mismatched_commitment", "Mismatched commitment",
 );

-function generateDecimalSas(sasBytes) {
+function generateDecimalSas(sasBytes: number[]): [number, number, number] {
    /**
     *      +--------+--------+--------+--------+--------+
     *      | Byte 0 | Byte 1 | Byte 2 | Byte 3 | Byte 4 |
@@ -64,7 +67,9 @@ function generateDecimalSas(sasBytes) {
    ];
 }

-const emojiMapping = [
+type EmojiMapping = [emoji: string, name: string];
+
+const emojiMapping: EmojiMapping[] = [
    ["🐶", "dog"],        //  0
    ["🐱", "cat"],        //  1
    ["🦁", "lion"],       //  2
@@ -131,7 +136,7 @@ const emojiMapping = [
    ["📌", "pin"],        // 63
 ];

-function generateEmojiSas(sasBytes) {
+function generateEmojiSas(sasBytes: number[]): EmojiMapping[] {
    const emojis = [
        // just like base64 encoding
        sasBytes[0] >> 2,
@@ -151,8 +156,20 @@ const sasGenerators = {
    emoji: generateEmojiSas,
 };

-function generateSas(sasBytes, methods) {
-    const sas = {};
+export interface IGeneratedSas {
+    decimal?: [number, number, number];
+    emoji?: EmojiMapping[];
+}
+
+export interface ISasEvent {
+    sas: IGeneratedSas;
+    confirm(): Promise<void>;
+    cancel(): void;
+    mismatch(): void;
+}
+
+function generateSas(sasBytes: number[], methods: string[]): IGeneratedSas {
+    const sas: IGeneratedSas = {};
    for (const method of methods) {
        if (method in sasGenerators) {
            sas[method] = sasGenerators[method](sasBytes);
@@ -166,7 +183,7 @@ const macMethods = {
    "hmac-sha256": "calculate_mac_long_kdf",
 };

-function calculateMAC(olmSAS, method) {
+function calculateMAC(olmSAS: OlmSAS, method: string) {
    return function(...args) {
        const macFunction = olmSAS[macMethods[method]];
        const mac = macFunction.apply(olmSAS, args);
@@ -176,23 +193,23 @@ function calculateMAC(olmSAS, method) {
 }

 const calculateKeyAgreement = {
-    "curve25519-hkdf-sha256": function(sas, olmSAS, bytes) {
-        const ourInfo = `${sas._baseApis.getUserId()}|${sas._baseApis.deviceId}|`
+    "curve25519-hkdf-sha256": function(sas: SAS, olmSAS: OlmSAS, bytes: number): Uint8Array {
+        const ourInfo = `${sas.baseApis.getUserId()}|${sas.baseApis.deviceId}|`
              + `${sas.ourSASPubKey}|`;
        const theirInfo = `${sas.userId}|${sas.deviceId}|${sas.theirSASPubKey}|`;
        const sasInfo =
            "MATRIX_KEY_VERIFICATION_SAS|"
              + (sas.initiatedByMe ? ourInfo + theirInfo : theirInfo + ourInfo)
-              + sas._channel.transactionId;
+              + sas.channel.transactionId;
        return olmSAS.generate_bytes(sasInfo, bytes);
    },
-    "curve25519": function(sas, olmSAS, bytes) {
-        const ourInfo = `${sas._baseApis.getUserId()}${sas._baseApis.deviceId}`;
+    "curve25519": function(sas: SAS, olmSAS: OlmSAS, bytes: number): Uint8Array {
+        const ourInfo = `${sas.baseApis.getUserId()}${sas.baseApis.deviceId}`;
        const theirInfo = `${sas.userId}${sas.deviceId}`;
        const sasInfo =
            "MATRIX_KEY_VERIFICATION_SAS"
              + (sas.initiatedByMe ? ourInfo + theirInfo : theirInfo + ourInfo)
-              + sas._channel.transactionId;
+              + sas.channel.transactionId;
        return olmSAS.generate_bytes(sasInfo, bytes);
    },
 };
@@ -211,37 +228,51 @@ const HASHES_SET = new Set(HASHES_LIST);
 const MAC_SET = new Set(MAC_LIST);
 const SAS_SET = new Set(SAS_LIST);

-function intersection(anArray, aSet) {
+function intersection<T>(anArray: T[], aSet: Set<T>): T[] {
    return anArray instanceof Array ? anArray.filter(x => aSet.has(x)) : [];
 }

+export enum SasEvent {
+    ShowSas = "show_sas",
+}
+
+type EventHandlerMap = {
+    [SasEvent.ShowSas]: (sas: ISasEvent) => void;
+} & VerificationEventHandlerMap;
+
 /**
 * @alias module:crypto/verification/SAS
 * @extends {module:crypto/verification/Base}
 */
-export class SAS extends Base {
-    static get NAME() {
+export class SAS extends Base<SasEvent, EventHandlerMap> {
+    private waitingForAccept: boolean;
+    public ourSASPubKey: string;
+    public theirSASPubKey: string;
+    public sasEvent: ISasEvent;
+
+    // eslint-disable-next-line @typescript-eslint/naming-convention
+    public static get NAME(): string {
        return "m.sas.v1";
    }

-    get events() {
+    public get events(): string[] {
        return EVENTS;
    }

-    async _doVerification() {
+    protected doVerification = async (): Promise<void> => {
        await global.Olm.init();
        olmutil = olmutil || new global.Olm.Utility();

        // make sure user's keys are downloaded
-        await this._baseApis.downloadKeys([this.userId]);
+        await this.baseApis.downloadKeys([this.userId]);

        let retry = false;
        do {
            try {
                if (this.initiatedByMe) {
-                    return await this._doSendVerification();
+                    return await this.doSendVerification();
                } else {
-                    return await this._doRespondVerification();
+                    return await this.doRespondVerification();
                }
            } catch (err) {
                if (err instanceof SwitchStartEventError) {
@@ -253,38 +284,37 @@ export class SAS extends Base {
                }
            }
        } while (retry);
-    }
+    };

-    canSwitchStartEvent(event) {
+    public canSwitchStartEvent(event: MatrixEvent): boolean {
        if (event.getType() !== START_TYPE) {
            return false;
        }
        const content = event.getContent();
-        return content && content.method === SAS.NAME &&
-            this._waitingForAccept;
+        return content && content.method === SAS.NAME && this.waitingForAccept;
    }

-    async _sendStart() {
-        const startContent = this._channel.completeContent(START_TYPE, {
+    private async sendStart(): Promise<Record<string, any>> {
+        const startContent = this.channel.completeContent(START_TYPE, {
            method: SAS.NAME,
-            from_device: this._baseApis.deviceId,
+            from_device: this.baseApis.deviceId,
            key_agreement_protocols: KEY_AGREEMENT_LIST,
            hashes: HASHES_LIST,
            message_authentication_codes: MAC_LIST,
            // FIXME: allow app to specify what SAS methods can be used
            short_authentication_string: SAS_LIST,
        });
-        await this._channel.sendCompleted(START_TYPE, startContent);
+        await this.channel.sendCompleted(START_TYPE, startContent);
        return startContent;
    }

-    async _doSendVerification() {
-        this._waitingForAccept = true;
+    private async doSendVerification(): Promise<void> {
+        this.waitingForAccept = true;
        let startContent;
        if (this.startEvent) {
-            startContent = this._channel.completedContentFromEvent(this.startEvent);
+            startContent = this.channel.completedContentFromEvent(this.startEvent);
        } else {
-            startContent = await this._sendStart();
+            startContent = await this.sendStart();
        }

        // we might have switched to a different start event,
@@ -297,9 +327,9 @@ export class SAS extends Base {

        let e;
        try {
-            e = await this._waitForEvent("m.key.verification.accept");
+            e = await this.waitForEvent("m.key.verification.accept");
        } finally {
-            this._waitingForAccept = false;
+            this.waitingForAccept = false;
        }
        let content = e.getContent();
        const sasMethods
@@ -319,11 +349,11 @@ export class SAS extends Base {
        const olmSAS = new global.Olm.SAS();
        try {
            this.ourSASPubKey = olmSAS.get_pubkey();
-            await this._send("m.key.verification.key", {
+            await this.send("m.key.verification.key", {
                key: this.ourSASPubKey,
            });

-            e = await this._waitForEvent("m.key.verification.key");
+            e = await this.waitForEvent("m.key.verification.key");
            // FIXME: make sure event is properly formed
            content = e.getContent();
            const commitmentStr = content.key + anotherjson.stringify(startContent);
@@ -335,12 +365,12 @@ export class SAS extends Base {
            olmSAS.set_their_key(content.key);

            const sasBytes = calculateKeyAgreement[keyAgreement](this, olmSAS, 6);
-            const verifySAS = new Promise((resolve, reject) => {
+            const verifySAS = new Promise<void>((resolve, reject) => {
                this.sasEvent = {
                    sas: generateSas(sasBytes, sasMethods),
                    confirm: async () => {
                        try {
-                            await this._sendMAC(olmSAS, macMethod);
+                            await this.sendMAC(olmSAS, macMethod);
                            resolve();
                        } catch (err) {
                            reject(err);
@@ -349,58 +379,49 @@ export class SAS extends Base {
                    cancel: () => reject(newUserCancelledError()),
                    mismatch: () => reject(newMismatchedSASError()),
                };
-                this.emit("show_sas", this.sasEvent);
+                this.emit(SasEvent.ShowSas, this.sasEvent);
            });

            [e] = await Promise.all([
-                this._waitForEvent("m.key.verification.mac")
+                this.waitForEvent("m.key.verification.mac")
                    .then((e) => {
                        // we don't expect any more messages from the other
                        // party, and they may send a m.key.verification.done
                        // when they're done on their end
-                        this._expectedEvent = "m.key.verification.done";
+                        this.expectedEvent = "m.key.verification.done";
                        return e;
                    }),
                verifySAS,
            ]);
            content = e.getContent();
-            await this._checkMAC(olmSAS, content, macMethod);
+            await this.checkMAC(olmSAS, content, macMethod);
        } finally {
            olmSAS.free();
        }
    }

-    async _doRespondVerification() {
+    private async doRespondVerification(): Promise<void> {
        // as m.related_to is not included in the encrypted content in e2e rooms,
        // we need to make sure it is added
-        let content = this._channel.completedContentFromEvent(this.startEvent);
+        let content = this.channel.completedContentFromEvent(this.startEvent);

        // Note: we intersect using our pre-made lists, rather than the sets,
        // so that the result will be in our order of preference.  Then
        // fetching the first element from the array will give our preferred
        // method out of the ones offered by the other party.
-        const keyAgreement
-              = intersection(
-                  KEY_AGREEMENT_LIST, new Set(content.key_agreement_protocols),
-              )[0];
-        const hashMethod
-              = intersection(HASHES_LIST, new Set(content.hashes))[0];
-        const macMethod
-              = intersection(MAC_LIST, new Set(content.message_authentication_codes))[0];
+        const keyAgreement = intersection(KEY_AGREEMENT_LIST, new Set(content.key_agreement_protocols))[0];
+        const hashMethod = intersection(HASHES_LIST, new Set(content.hashes))[0];
+        const macMethod = intersection(MAC_LIST, new Set(content.message_authentication_codes))[0];
        // FIXME: allow app to specify what SAS methods can be used
-        const sasMethods
-              = intersection(content.short_authentication_string, SAS_SET);
-        if (!(keyAgreement !== undefined
-              && hashMethod !== undefined
-              && macMethod !== undefined
-              && sasMethods.length)) {
+        const sasMethods = intersection(content.short_authentication_string, SAS_SET);
+        if (!(keyAgreement !== undefined && hashMethod !== undefined && macMethod !== undefined && sasMethods.length)) {
            throw newUnknownMethodError();
        }

        const olmSAS = new global.Olm.SAS();
        try {
            const commitmentStr = olmSAS.get_pubkey() + anotherjson.stringify(content);
-            await this._send("m.key.verification.accept", {
+            await this.send("m.key.verification.accept", {
                key_agreement_protocol: keyAgreement,
                hash: hashMethod,
                message_authentication_code: macMethod,
@@ -409,23 +430,23 @@ export class SAS extends Base {
                commitment: olmutil.sha256(commitmentStr),
            });

-            let e = await this._waitForEvent("m.key.verification.key");
+            let e = await this.waitForEvent("m.key.verification.key");
            // FIXME: make sure event is properly formed
            content = e.getContent();
            this.theirSASPubKey = content.key;
            olmSAS.set_their_key(content.key);
            this.ourSASPubKey = olmSAS.get_pubkey();
-            await this._send("m.key.verification.key", {
+            await this.send("m.key.verification.key", {
                key: this.ourSASPubKey,
            });

            const sasBytes = calculateKeyAgreement[keyAgreement](this, olmSAS, 6);
-            const verifySAS = new Promise((resolve, reject) => {
+            const verifySAS = new Promise<void>((resolve, reject) => {
                this.sasEvent = {
                    sas: generateSas(sasBytes, sasMethods),
                    confirm: async () => {
                        try {
-                            await this._sendMAC(olmSAS, macMethod);
+                            await this.sendMAC(olmSAS, macMethod);
                            resolve();
                        } catch (err) {
                            reject(err);
@@ -434,43 +455,43 @@ export class SAS extends Base {
                    cancel: () => reject(newUserCancelledError()),
                    mismatch: () => reject(newMismatchedSASError()),
                };
-                this.emit("show_sas", this.sasEvent);
+                this.emit(SasEvent.ShowSas, this.sasEvent);
            });

            [e] = await Promise.all([
-                this._waitForEvent("m.key.verification.mac")
+                this.waitForEvent("m.key.verification.mac")
                    .then((e) => {
                        // we don't expect any more messages from the other
                        // party, and they may send a m.key.verification.done
                        // when they're done on their end
-                        this._expectedEvent = "m.key.verification.done";
+                        this.expectedEvent = "m.key.verification.done";
                        return e;
                    }),
                verifySAS,
            ]);
            content = e.getContent();
-            await this._checkMAC(olmSAS, content, macMethod);
+            await this.checkMAC(olmSAS, content, macMethod);
        } finally {
            olmSAS.free();
        }
    }

-    _sendMAC(olmSAS, method) {
+    private sendMAC(olmSAS: OlmSAS, method: string): Promise<void> {
        const mac = {};
        const keyList = [];
        const baseInfo = "MATRIX_KEY_VERIFICATION_MAC"
-              + this._baseApis.getUserId() + this._baseApis.deviceId
+              + this.baseApis.getUserId() + this.baseApis.deviceId
              + this.userId + this.deviceId
-              + this._channel.transactionId;
+              + this.channel.transactionId;

-        const deviceKeyId = `ed25519:${this._baseApis.deviceId}`;
+        const deviceKeyId = `ed25519:${this.baseApis.deviceId}`;
        mac[deviceKeyId] = calculateMAC(olmSAS, method)(
-            this._baseApis.getDeviceEd25519Key(),
+            this.baseApis.getDeviceEd25519Key(),
            baseInfo + deviceKeyId,
        );
        keyList.push(deviceKeyId);

-        const crossSigningId = this._baseApis.getCrossSigningId();
+        const crossSigningId = this.baseApis.getCrossSigningId();
        if (crossSigningId) {
            const crossSigningKeyId = `ed25519:${crossSigningId}`;
            mac[crossSigningKeyId] = calculateMAC(olmSAS, method)(
@@ -484,14 +505,14 @@ export class SAS extends Base {
            keyList.sort().join(","),
            baseInfo + "KEY_IDS",
        );
-        return this._send("m.key.verification.mac", { mac, keys });
+        return this.send("m.key.verification.mac", { mac, keys });
    }

-    async _checkMAC(olmSAS, content, method) {
+    private async checkMAC(olmSAS: OlmSAS, content: IContent, method: string): Promise<void> {
        const baseInfo = "MATRIX_KEY_VERIFICATION_MAC"
              + this.userId + this.deviceId
-              + this._baseApis.getUserId() + this._baseApis.deviceId
-              + this._channel.transactionId;
+              + this.baseApis.getUserId() + this.baseApis.deviceId
+              + this.channel.transactionId;

        if (content.keys !== calculateMAC(olmSAS, method)(
            Object.keys(content.mac).sort().join(","),
@@ -500,7 +521,7 @@ export class SAS extends Base {
            throw newKeyMismatchError();
        }

-        await this._verifyKeys(this.userId, content.mac, (keyId, device, keyInfo) => {
+        await this.verifyKeys(this.userId, content.mac, (keyId, device, keyInfo) => {
            if (keyInfo !== calculateMAC(olmSAS, method)(
                device.keys[keyId],
                baseInfo + keyId,
@@ -0,0 +1,34 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { MatrixEvent } from "../../../models/event";
+import { VerificationRequest } from "./VerificationRequest";
+
+export interface IVerificationChannel {
+    request?: VerificationRequest;
+    readonly userId: string;
+    readonly roomId?: string;
+    readonly deviceId?: string;
+    readonly transactionId: string;
+    readonly receiveStartFromOtherDevices?: boolean;
+    getTimestamp(event: MatrixEvent): number;
+    send(type: string, uncompletedContent: Record<string, any>): Promise<void>;
+    completeContent(type: string, content: Record<string, any>): Record<string, any>;
+    sendCompleted(type: string, content: Record<string, any>): Promise<void>;
+    completedContentFromEvent(event: MatrixEvent): Record<string, any>;
+    canCreateRequest(type: string): boolean;
+    handleEvent(event: MatrixEvent, request: VerificationRequest, isLiveEvent: boolean): Promise<void>;
+}
@@ -22,8 +22,13 @@ import {
    START_TYPE,
 } from "./VerificationRequest";
 import { logger } from '../../../logger';
+import { IVerificationChannel } from "./Channel";
+import { EventType } from "../../../@types/event";
+import { MatrixClient } from "../../../client";
+import { MatrixEvent } from "../../../models/event";
+import { IRequestsMap } from "../..";

-const MESSAGE_TYPE = "m.room.message";
+const MESSAGE_TYPE = EventType.RoomMessage;
 const M_REFERENCE = "m.reference";
 const M_RELATES_TO = "m.relates_to";

@@ -31,36 +36,34 @@ const M_RELATES_TO = "m.relates_to";
 * A key verification channel that sends verification events in the timeline of a room.
 * Uses the event id of the initial m.key.verification.request event as a transaction id.
 */
-export class InRoomChannel {
+export class InRoomChannel implements IVerificationChannel {
+    private requestEventId: string = null;
+
    /**
     * @param {MatrixClient} client the matrix client, to send messages with and get current user & device from.
     * @param {string} roomId id of the room where verification events should be posted in, should be a DM with the given user.
     * @param {string} userId id of user that the verification request is directed at, should be present in the room.
     */
-    constructor(client, roomId, userId = null) {
-        this._client = client;
-        this._roomId = roomId;
-        this.userId = userId;
-        this._requestEventId = null;
+    constructor(
+        private readonly client: MatrixClient,
+        public readonly roomId: string,
+        public userId: string = null,
+    ) {
    }

-    get receiveStartFromOtherDevices() {
+    public get receiveStartFromOtherDevices(): boolean {
        return true;
    }

-    get roomId() {
-        return this._roomId;
-    }
-
    /** The transaction id generated/used by this verification channel */
-    get transactionId() {
-        return this._requestEventId;
+    public get transactionId(): string {
+        return this.requestEventId;
    }

-    static getOtherPartyUserId(event, client) {
+    public static getOtherPartyUserId(event: MatrixEvent, client: MatrixClient): string {
        const type = InRoomChannel.getEventType(event);
        if (type !== REQUEST_TYPE) {
-           return;
+            return;
        }
        const ownUserId = client.getUserId();
        const sender = event.getSender();
@@ -78,25 +81,29 @@ export class InRoomChannel {
     * @param {MatrixEvent} event the event to get the timestamp of
     * @return {number} the timestamp when the event was sent
     */
-    getTimestamp(event) {
+    public getTimestamp(event: MatrixEvent): number {
        return event.getTs();
    }

    /**
     * Checks whether the given event type should be allowed to initiate a new VerificationRequest over this channel
     * @param {string} type the event type to check
-     * @returns {bool} boolean flag
+     * @returns {boolean} boolean flag
     */
-    static canCreateRequest(type) {
+    public static canCreateRequest(type: string): boolean {
        return type === REQUEST_TYPE;
    }

+    public canCreateRequest(type: string): boolean {
+        return InRoomChannel.canCreateRequest(type);
+    }
+
    /**
     * Extract the transaction id used by a given key verification event, if any
     * @param {MatrixEvent} event the event
     * @returns {string} the transaction id
     */
-    static getTransactionId(event) {
+    public static getTransactionId(event: MatrixEvent): string {
        if (InRoomChannel.getEventType(event) === REQUEST_TYPE) {
            return event.getId();
        } else {
@@ -114,9 +121,9 @@ export class InRoomChannel {
     * `handleEvent` can do more checks and choose to ignore invalid events.
     * @param {MatrixEvent} event the event to validate
     * @param {MatrixClient} client the client to get the current user and device id from
-     * @returns {bool} whether the event is valid and should be passed to handleEvent
+     * @returns {boolean} whether the event is valid and should be passed to handleEvent
     */
-    static validateEvent(event, client) {
+    public static validateEvent(event: MatrixEvent, client: MatrixClient): boolean {
        const txnId = InRoomChannel.getTransactionId(event);
        if (typeof txnId !== "string" || txnId.length === 0) {
            return false;
@@ -152,7 +159,7 @@ export class InRoomChannel {
     * @param {MatrixEvent} event the event to get the type of
     * @returns {string} the "symbolic" event type
     */
-    static getEventType(event) {
+    public static getEventType(event: MatrixEvent): string {
        const type = event.getType();
        if (type === MESSAGE_TYPE) {
            const content = event.getContent();
@@ -174,10 +181,10 @@ export class InRoomChannel {
     * Changes the state of the channel, request, and verifier in response to a key verification event.
     * @param {MatrixEvent} event to handle
     * @param {VerificationRequest} request the request to forward handling to
-     * @param {bool} isLiveEvent whether this is an even received through sync or not
-     * @returns {Promise} a promise that resolves when any requests as an anwser to the passed-in event are sent.
+     * @param {boolean} isLiveEvent whether this is an even received through sync or not
+     * @returns {Promise} a promise that resolves when any requests as an answer to the passed-in event are sent.
     */
-    async handleEvent(event, request, isLiveEvent) {
+    public async handleEvent(event: MatrixEvent, request: VerificationRequest, isLiveEvent = false): Promise<void> {
        // prevent processing the same event multiple times, as under
        // some circumstances Room.timeline can get emitted twice for the same event
        if (request.hasEventId(event.getId())) {
@@ -187,18 +194,18 @@ export class InRoomChannel {
        // do validations that need state (roomId, userId),
        // ignore if invalid

-        if (event.getRoomId() !== this._roomId) {
+        if (event.getRoomId() !== this.roomId) {
            return;
        }
        // set userId if not set already
        if (this.userId === null) {
-            const userId = InRoomChannel.getOtherPartyUserId(event, this._client);
+            const userId = InRoomChannel.getOtherPartyUserId(event, this.client);
            if (userId) {
                this.userId = userId;
            }
        }
        // ignore events not sent by us or the other party
-        const ownUserId = this._client.getUserId();
+        const ownUserId = this.client.getUserId();
        const sender = event.getSender();
        if (this.userId !== null) {
            if (sender !== ownUserId && sender !== this.userId) {
@@ -207,12 +214,12 @@ export class InRoomChannel {
                return;
            }
        }
-        if (this._requestEventId === null) {
-            this._requestEventId = InRoomChannel.getTransactionId(event);
+        if (this.requestEventId === null) {
+            this.requestEventId = InRoomChannel.getTransactionId(event);
        }

        const isRemoteEcho = !!event.getUnsigned().transaction_id;
-        const isSentByUs = event.getSender() === this._client.getUserId();
+        const isSentByUs = event.getSender() === this.client.getUserId();

        return await request.handleEvent(
            type, event, isLiveEvent, isRemoteEcho, isSentByUs);
@@ -226,13 +233,14 @@ export class InRoomChannel {
     * @param {MatrixEvent} event the received event
     * @returns {Object} the content object with the relation added again
     */
-    completedContentFromEvent(event) {
+    public completedContentFromEvent(event: MatrixEvent): Record<string, any> {
        // ensure m.related_to is included in e2ee rooms
        // as the field is excluded from encryption
        const content = Object.assign({}, event.getContent());
        content[M_RELATES_TO] = event.getRelation();
        return content;
    }
+
    /**
     * Add all the fields to content needed for sending it over this channel.
     * This is public so verification methods (SAS uses this) can get the exact
@@ -242,15 +250,15 @@ export class InRoomChannel {
     * @param {object} content the (incomplete) content
     * @returns {object} the complete content, as it will be sent.
     */
-    completeContent(type, content) {
+    public completeContent(type: string, content: Record<string, any>): Record<string, any> {
        content = Object.assign({}, content);
        if (type === REQUEST_TYPE || type === READY_TYPE || type === START_TYPE) {
-            content.from_device = this._client.getDeviceId();
+            content.from_device = this.client.getDeviceId();
        }
        if (type === REQUEST_TYPE) {
            // type is mapped to m.room.message in the send method
            content = {
-                body: this._client.getUserId() + " is requesting to verify " +
+                body: this.client.getUserId() + " is requesting to verify " +
                    "your key, but your client does not support in-chat key " +
                    "verification.  You will need to use legacy key " +
                    "verification to verify keys.",
@@ -274,7 +282,7 @@ export class InRoomChannel {
     * @param {object} uncompletedContent the (incomplete) content
     * @returns {Promise} the promise of the request
     */
-    send(type, uncompletedContent) {
+    public send(type: string, uncompletedContent: Record<string, any>): Promise<void> {
        const content = this.completeContent(type, uncompletedContent);
        return this.sendCompleted(type, content);
    }
@@ -285,74 +293,68 @@ export class InRoomChannel {
     * @param {object} content
     * @returns {Promise} the promise of the request
     */
-    async sendCompleted(type, content) {
+    public async sendCompleted(type: string, content: Record<string, any>): Promise<void> {
        let sendType = type;
        if (type === REQUEST_TYPE) {
            sendType = MESSAGE_TYPE;
        }
-        const response = await this._client.sendEvent(this._roomId, sendType, content);
+        const response = await this.client.sendEvent(this.roomId, sendType, content);
        if (type === REQUEST_TYPE) {
-            this._requestEventId = response.event_id;
+            this.requestEventId = response.event_id;
        }
    }
 }

-export class InRoomRequests {
-    constructor() {
-        this._requestsByRoomId = new Map();
-    }
+export class InRoomRequests implements IRequestsMap {
+    private requestsByRoomId = new Map<string, Map<string, VerificationRequest>>();

-    getRequest(event) {
+    public getRequest(event: MatrixEvent): VerificationRequest {
        const roomId = event.getRoomId();
        const txnId = InRoomChannel.getTransactionId(event);
-        return this._getRequestByTxnId(roomId, txnId);
+        return this.getRequestByTxnId(roomId, txnId);
    }

-    getRequestByChannel(channel) {
-        return this._getRequestByTxnId(channel.roomId, channel.transactionId);
+    public getRequestByChannel(channel: InRoomChannel): VerificationRequest {
+        return this.getRequestByTxnId(channel.roomId, channel.transactionId);
    }

-    _getRequestByTxnId(roomId, txnId) {
-        const requestsByTxnId = this._requestsByRoomId.get(roomId);
+    private getRequestByTxnId(roomId: string, txnId: string): VerificationRequest {
+        const requestsByTxnId = this.requestsByRoomId.get(roomId);
        if (requestsByTxnId) {
            return requestsByTxnId.get(txnId);
        }
    }

-    setRequest(event, request) {
-        this._setRequest(
-            event.getRoomId(),
-            InRoomChannel.getTransactionId(event),
-            request,
-        );
+    public setRequest(event: MatrixEvent, request: VerificationRequest): void {
+        this.doSetRequest(event.getRoomId(), InRoomChannel.getTransactionId(event), request);
    }

-    setRequestByChannel(channel, request) {
-        this._setRequest(channel.roomId, channel.transactionId, request);
+    public setRequestByChannel(channel: IVerificationChannel, request: VerificationRequest): void {
+        this.doSetRequest(channel.roomId, channel.transactionId, request);
    }

-    _setRequest(roomId, txnId, request) {
-        let requestsByTxnId = this._requestsByRoomId.get(roomId);
+    private doSetRequest(roomId: string, txnId: string, request: VerificationRequest): void {
+        let requestsByTxnId = this.requestsByRoomId.get(roomId);
        if (!requestsByTxnId) {
            requestsByTxnId = new Map();
-            this._requestsByRoomId.set(roomId, requestsByTxnId);
+            this.requestsByRoomId.set(roomId, requestsByTxnId);
        }
        requestsByTxnId.set(txnId, request);
    }

-    removeRequest(event) {
+    public removeRequest(event: MatrixEvent): void {
        const roomId = event.getRoomId();
-        const requestsByTxnId = this._requestsByRoomId.get(roomId);
+        const requestsByTxnId = this.requestsByRoomId.get(roomId);
        if (requestsByTxnId) {
            requestsByTxnId.delete(InRoomChannel.getTransactionId(event));
            if (requestsByTxnId.size === 0) {
-                this._requestsByRoomId.delete(roomId);
+                this.requestsByRoomId.delete(roomId);
            }
        }
    }

-    findRequestInProgress(roomId) {
-        const requestsByTxnId = this._requestsByRoomId.get(roomId);
+    public findRequestInProgress(roomId: string): VerificationRequest {
+        const requestsByTxnId = this.requestsByRoomId.get(roomId);
        if (requestsByTxnId) {
            for (const request of requestsByTxnId.values()) {
                if (request.pending) {
@@ -28,26 +28,32 @@ import {
 } from "./VerificationRequest";
 import { errorFromEvent, newUnexpectedMessageError } from "../Error";
 import { MatrixEvent } from "../../../models/event";
+import { IVerificationChannel } from "./Channel";
+import { MatrixClient } from "../../../client";
+import { IRequestsMap } from '../..';
+
+export type Request = VerificationRequest<ToDeviceChannel>;

 /**
 * A key verification channel that sends verification events over to_device messages.
 * Generates its own transaction ids.
 */
-export class ToDeviceChannel {
-    // userId and devices of user we're about to verify
-    constructor(client, userId, devices, transactionId = null, deviceId = null) {
-        this._client = client;
-        this.userId = userId;
-        this._devices = devices;
-        this.transactionId = transactionId;
-        this._deviceId = deviceId;
-    }
+export class ToDeviceChannel implements IVerificationChannel {
+    public request?: VerificationRequest;

-    isToDevices(devices) {
-        if (devices.length === this._devices.length) {
+    // userId and devices of user we're about to verify
+    constructor(
+        private readonly client: MatrixClient,
+        public readonly userId: string,
+        private readonly devices: string[],
+        public transactionId: string = null,
+        public deviceId: string = null,
+    ) {}
+
+    public isToDevices(devices: string[]): boolean {
+        if (devices.length === this.devices.length) {
            for (const device of devices) {
-                const d = this._devices.find(d => d.deviceId === device.deviceId);
-                if (!d) {
+                if (!this.devices.includes(device)) {
                    return false;
                }
            }
@@ -57,11 +63,7 @@ export class ToDeviceChannel {
        }
    }

-    get deviceId() {
-        return this._deviceId;
-    }
-
-    static getEventType(event) {
+    public static getEventType(event: MatrixEvent): string {
        return event.getType();
    }

@@ -70,7 +72,7 @@ export class ToDeviceChannel {
     * @param {MatrixEvent} event the event
     * @returns {string} the transaction id
     */
-    static getTransactionId(event) {
+    public static getTransactionId(event: MatrixEvent): string {
        const content = event.getContent();
        return content && content.transaction_id;
    }
@@ -78,12 +80,16 @@ export class ToDeviceChannel {
    /**
     * Checks whether the given event type should be allowed to initiate a new VerificationRequest over this channel
     * @param {string} type the event type to check
-     * @returns {bool} boolean flag
+     * @returns {boolean} boolean flag
     */
-    static canCreateRequest(type) {
+    public static canCreateRequest(type: string): boolean {
        return type === REQUEST_TYPE || type === START_TYPE;
    }

+    public canCreateRequest(type: string): boolean {
+        return ToDeviceChannel.canCreateRequest(type);
+    }
+
    /**
     * Checks whether this event is a well-formed key verification event.
     * This only does checks that don't rely on the current state of a potentially already channel
@@ -91,9 +97,9 @@ export class ToDeviceChannel {
     * `handleEvent` can do more checks and choose to ignore invalid events.
     * @param {MatrixEvent} event the event to validate
     * @param {MatrixClient} client the client to get the current user and device id from
-     * @returns {bool} whether the event is valid and should be passed to handleEvent
+     * @returns {boolean} whether the event is valid and should be passed to handleEvent
     */
-    static validateEvent(event, client) {
+    public static validateEvent(event: MatrixEvent, client: MatrixClient): boolean {
        if (event.isCancelled()) {
            logger.warn("Ignoring flagged verification request from "
                 + event.getSender());
@@ -134,7 +140,7 @@ export class ToDeviceChannel {
     * @param {MatrixEvent} event the event to get the timestamp of
     * @return {number} the timestamp when the event was sent
     */
-    getTimestamp(event) {
+    public getTimestamp(event: MatrixEvent): number {
        const content = event.getContent();
        return content && content.timestamp;
    }
@@ -143,10 +149,10 @@ export class ToDeviceChannel {
     * Changes the state of the channel, request, and verifier in response to a key verification event.
     * @param {MatrixEvent} event to handle
     * @param {VerificationRequest} request the request to forward handling to
-     * @param {bool} isLiveEvent whether this is an even received through sync or not
-     * @returns {Promise} a promise that resolves when any requests as an anwser to the passed-in event are sent.
+     * @param {boolean} isLiveEvent whether this is an even received through sync or not
+     * @returns {Promise} a promise that resolves when any requests as an answer to the passed-in event are sent.
     */
-    async handleEvent(event, request, isLiveEvent) {
+    public async handleEvent(event: MatrixEvent, request: Request, isLiveEvent = false): Promise<void> {
        const type = event.getType();
        const content = event.getContent();
        if (type === REQUEST_TYPE || type === READY_TYPE || type === START_TYPE) {
@@ -155,17 +161,16 @@ export class ToDeviceChannel {
            }
            const deviceId = content.from_device;
            // adopt deviceId if not set before and valid
-            if (!this._deviceId && this._devices.includes(deviceId)) {
-                this._deviceId = deviceId;
+            if (!this.deviceId && this.devices.includes(deviceId)) {
+                this.deviceId = deviceId;
            }
-            // if no device id or different from addopted one, cancel with sender
-            if (!this._deviceId || this._deviceId !== deviceId) {
+            // if no device id or different from adopted one, cancel with sender
+            if (!this.deviceId || this.deviceId !== deviceId) {
                // also check that message came from the device we sent the request to earlier on
                // and do send a cancel message to that device
                // (but don't cancel the request for the device we should be talking to)
-                const cancelContent =
-                    this.completeContent(errorFromEvent(newUnexpectedMessageError()));
-                return this._sendToDevices(CANCEL_TYPE, cancelContent, [deviceId]);
+                const cancelContent = this.completeContent(CANCEL_TYPE, errorFromEvent(newUnexpectedMessageError()));
+                return this.sendToDevices(CANCEL_TYPE, cancelContent, [deviceId]);
            }
        }
        const wasStarted = request.phase === PHASE_STARTED ||
@@ -178,16 +183,16 @@ export class ToDeviceChannel {

        const isAcceptingEvent = type === START_TYPE || type === READY_TYPE;
        // the request has picked a ready or start event, tell the other devices about it
-        if (isAcceptingEvent && !wasStarted && isStarted && this._deviceId) {
-            const nonChosenDevices = this._devices.filter(
-                d => d !== this._deviceId && d !== this._client.getDeviceId(),
+        if (isAcceptingEvent && !wasStarted && isStarted && this.deviceId) {
+            const nonChosenDevices = this.devices.filter(
+                d => d !== this.deviceId && d !== this.client.getDeviceId(),
            );
            if (nonChosenDevices.length) {
-                const message = this.completeContent({
+                const message = this.completeContent(CANCEL_TYPE, {
                    code: "m.accepted",
                    reason: "Verification request accepted by another device",
                });
-                await this._sendToDevices(CANCEL_TYPE, message, nonChosenDevices);
+                await this.sendToDevices(CANCEL_TYPE, message, nonChosenDevices);
            }
        }
    }
@@ -197,7 +202,7 @@ export class ToDeviceChannel {
     * @param {MatrixEvent} event the received event
     * @returns {Object} the content object
     */
-    completedContentFromEvent(event) {
+    public completedContentFromEvent(event: MatrixEvent): Record<string, any> {
        return event.getContent();
    }

@@ -210,14 +215,14 @@ export class ToDeviceChannel {
     * @param {object} content the (incomplete) content
     * @returns {object} the complete content, as it will be sent.
     */
-    completeContent(type, content) {
+    public completeContent(type: string, content: Record<string, any>): Record<string, any> {
        // make a copy
        content = Object.assign({}, content);
        if (this.transactionId) {
            content.transaction_id = this.transactionId;
        }
        if (type === REQUEST_TYPE || type === READY_TYPE || type === START_TYPE) {
-            content.from_device = this._client.getDeviceId();
+            content.from_device = this.client.getDeviceId();
        }
        if (type === REQUEST_TYPE) {
            content.timestamp = Date.now();
@@ -231,7 +236,7 @@ export class ToDeviceChannel {
     * @param {object} uncompletedContent the (incomplete) content
     * @returns {Promise} the promise of the request
     */
-    send(type, uncompletedContent = {}) {
+    public send(type: string, uncompletedContent: Record<string, any> = {}): Promise<void> {
        // create transaction id when sending request
        if ((type === REQUEST_TYPE || type === START_TYPE) && !this.transactionId) {
            this.transactionId = ToDeviceChannel.makeTransactionId();
@@ -246,21 +251,21 @@ export class ToDeviceChannel {
     * @param {object} content
     * @returns {Promise} the promise of the request
     */
-    async sendCompleted(type, content) {
+    public async sendCompleted(type: string, content: Record<string, any>): Promise<void> {
        let result;
-        if (type === REQUEST_TYPE) {
-            result = await this._sendToDevices(type, content, this._devices);
+        if (type === REQUEST_TYPE || (type === CANCEL_TYPE && !this.deviceId)) {
+            result = await this.sendToDevices(type, content, this.devices);
        } else {
-            result = await this._sendToDevices(type, content, [this._deviceId]);
+            result = await this.sendToDevices(type, content, [this.deviceId]);
        }
        // the VerificationRequest state machine requires remote echos of the event
        // the client sends itself, so we fake this for to_device messages
        const remoteEchoEvent = new MatrixEvent({
-            sender: this._client.getUserId(),
+            sender: this.client.getUserId(),
            content,
            type,
        });
-        await this._request.handleEvent(
+        await this.request.handleEvent(
            type,
            remoteEchoEvent,
            /*isLiveEvent=*/true,
@@ -270,16 +275,14 @@ export class ToDeviceChannel {
        return result;
    }

-    _sendToDevices(type, content, devices) {
+    private async sendToDevices(type: string, content: Record<string, any>, devices: string[]): Promise<void> {
        if (devices.length) {
-            const msgMap = {};
+            const msgMap: Record<string, Record<string, any>> = {};
            for (const deviceId of devices) {
                msgMap[deviceId] = content;
            }

-            return this._client.sendToDevice(type, { [this.userId]: msgMap });
-        } else {
-            return Promise.resolve();
+            await this.client.sendToDevice(type, { [this.userId]: msgMap });
        }
    }

@@ -287,68 +290,62 @@ export class ToDeviceChannel {
     * Allow Crypto module to create and know the transaction id before the .start event gets sent.
     * @returns {string} the transaction id
     */
-    static makeTransactionId() {
+    public static makeTransactionId(): string {
        return randomString(32);
    }
 }

-export class ToDeviceRequests {
-    constructor() {
-        this._requestsByUserId = new Map();
-    }
+export class ToDeviceRequests implements IRequestsMap {
+    private requestsByUserId = new Map<string, Map<string, Request>>();

-    getRequest(event) {
+    public getRequest(event: MatrixEvent): Request {
        return this.getRequestBySenderAndTxnId(
            event.getSender(),
            ToDeviceChannel.getTransactionId(event),
        );
    }

-    getRequestByChannel(channel) {
+    public getRequestByChannel(channel: ToDeviceChannel): Request {
        return this.getRequestBySenderAndTxnId(channel.userId, channel.transactionId);
    }

-    getRequestBySenderAndTxnId(sender, txnId) {
-        const requestsByTxnId = this._requestsByUserId.get(sender);
+    public getRequestBySenderAndTxnId(sender: string, txnId: string): Request {
+        const requestsByTxnId = this.requestsByUserId.get(sender);
        if (requestsByTxnId) {
            return requestsByTxnId.get(txnId);
        }
    }

-    setRequest(event, request) {
-        this.setRequestBySenderAndTxnId(
-            event.getSender(),
-            ToDeviceChannel.getTransactionId(event),
-            request,
-        );
+    public setRequest(event: MatrixEvent, request: Request): void {
+        this.setRequestBySenderAndTxnId(event.getSender(), ToDeviceChannel.getTransactionId(event), request);
    }

-    setRequestByChannel(channel, request) {
+    public setRequestByChannel(channel: ToDeviceChannel, request: Request): void {
        this.setRequestBySenderAndTxnId(channel.userId, channel.transactionId, request);
    }

-    setRequestBySenderAndTxnId(sender, txnId, request) {
-        let requestsByTxnId = this._requestsByUserId.get(sender);
+    public setRequestBySenderAndTxnId(sender: string, txnId: string, request: Request): void {
+        let requestsByTxnId = this.requestsByUserId.get(sender);
        if (!requestsByTxnId) {
            requestsByTxnId = new Map();
-            this._requestsByUserId.set(sender, requestsByTxnId);
+            this.requestsByUserId.set(sender, requestsByTxnId);
        }
        requestsByTxnId.set(txnId, request);
    }

-    removeRequest(event) {
+    public removeRequest(event: MatrixEvent): void {
        const userId = event.getSender();
-        const requestsByTxnId = this._requestsByUserId.get(userId);
+        const requestsByTxnId = this.requestsByUserId.get(userId);
        if (requestsByTxnId) {
            requestsByTxnId.delete(ToDeviceChannel.getTransactionId(event));
            if (requestsByTxnId.size === 0) {
-                this._requestsByUserId.delete(userId);
+                this.requestsByUserId.delete(userId);
            }
        }
    }

-    findRequestInProgress(userId, devices) {
-        const requestsByTxnId = this._requestsByUserId.get(userId);
+    public findRequestInProgress(userId: string, devices: string[]): Request {
+        const requestsByTxnId = this.requestsByUserId.get(userId);
        if (requestsByTxnId) {
            for (const request of requestsByTxnId.values()) {
                if (request.pending && request.channel.isToDevices(devices)) {
@@ -358,8 +355,8 @@ export class ToDeviceRequests {
        }
    }

-    getRequestsInProgress(userId) {
-        const requestsByTxnId = this._requestsByUserId.get(userId);
+    public getRequestsInProgress(userId: string): Request[] {
+        const requestsByTxnId = this.requestsByUserId.get(userId);
        if (requestsByTxnId) {
            return Array.from(requestsByTxnId.values()).filter(r => r.pending);
        }
@@ -1,6 +1,5 @@
 /*
-Copyright 2018 New Vector Ltd
-Copyright 2019 The Matrix.org Foundation C.I.C.
+Copyright 2018 - 2021 The Matrix.org Foundation C.I.C.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -16,7 +15,6 @@ limitations under the License.
 */

 import { logger } from '../../../logger';
-import { EventEmitter } from 'events';
 import {
    errorFactory,
    errorFromEvent,
@@ -24,6 +22,12 @@ import {
    newUnknownMethodError,
 } from "../Error";
 import { QRCodeData, SCAN_QR_CODE_METHOD } from "../QRCode";
+import { IVerificationChannel } from "./Channel";
+import { MatrixClient } from "../../../client";
+import { MatrixEvent } from "../../../models/event";
+import { VerificationBase } from "../Base";
+import { VerificationMethod } from "../../index";
+import { TypedEventEmitter } from "../../../models/typed-event-emitter";

 // How long after the event's timestamp that the request times out
 const TIMEOUT_FROM_EVENT_TS = 10 * 60 * 1000; // 10 minutes
@@ -44,12 +48,40 @@ export const CANCEL_TYPE = EVENT_PREFIX + "cancel";
 export const DONE_TYPE = EVENT_PREFIX + "done";
 export const READY_TYPE = EVENT_PREFIX + "ready";

-export const PHASE_UNSENT = 1;
-export const PHASE_REQUESTED = 2;
-export const PHASE_READY = 3;
-export const PHASE_STARTED = 4;
-export const PHASE_CANCELLED = 5;
-export const PHASE_DONE = 6;
+export enum Phase {
+    Unsent = 1,
+    Requested,
+    Ready,
+    Started,
+    Cancelled,
+    Done,
+}
+
+// Legacy export fields
+export const PHASE_UNSENT = Phase.Unsent;
+export const PHASE_REQUESTED = Phase.Requested;
+export const PHASE_READY = Phase.Ready;
+export const PHASE_STARTED = Phase.Started;
+export const PHASE_CANCELLED = Phase.Cancelled;
+export const PHASE_DONE = Phase.Done;
+
+interface ITargetDevice {
+    userId?: string;
+    deviceId?: string;
+}
+
+interface ITransition {
+    phase: Phase;
+    event?: MatrixEvent;
+}
+
+export enum VerificationRequestEvent {
+    Change = "change",
+}
+
+type EventHandlerMap = {
+    [VerificationRequestEvent.Change]: () => void;
+};

 /**
 * State machine for verification requests.
@@ -57,32 +89,40 @@ export const PHASE_DONE = 6;
 * send and receive verification events are put in `InRoomChannel` or `ToDeviceChannel`.
 * @event "change" whenever the state of the request object has changed.
 */
-export class VerificationRequest extends EventEmitter {
-    constructor(channel, verificationMethods, client) {
-        super();
-        this.channel = channel;
-        this.channel._request = this;
-        this._verificationMethods = verificationMethods;
-        this._client = client;
-        this._commonMethods = [];
-        this._setPhase(PHASE_UNSENT, false);
-        this._eventsByUs = new Map();
-        this._eventsByThem = new Map();
-        this._observeOnly = false;
-        this._timeoutTimer = null;
-        this._accepting = false;
-        this._declining = false;
-        this._verifierHasFinished = false;
-        this._cancelled = false;
-        this._chosenMethod = null;
-        // we keep a copy of the QR Code data (including other user master key) around
-        // for QR reciprocate verification, to protect against
-        // cross-signing identity reset between the .ready and .start event
-        // and signing the wrong key after .start
-        this._qrCodeData = null;
+export class VerificationRequest<
+    C extends IVerificationChannel = IVerificationChannel,
+> extends TypedEventEmitter<VerificationRequestEvent, EventHandlerMap> {
+    private eventsByUs = new Map<string, MatrixEvent>();
+    private eventsByThem = new Map<string, MatrixEvent>();
+    private _observeOnly = false;
+    private timeoutTimer: number = null;
+    private _accepting = false;
+    private _declining = false;
+    private verifierHasFinished = false;
+    private _cancelled = false;
+    private _chosenMethod: VerificationMethod = null;
+    // we keep a copy of the QR Code data (including other user master key) around
+    // for QR reciprocate verification, to protect against
+    // cross-signing identity reset between the .ready and .start event
+    // and signing the wrong key after .start
+    private _qrCodeData: QRCodeData = null;

-        // The timestamp when we received the request event from the other side
-        this._requestReceivedAt = null;
+    // The timestamp when we received the request event from the other side
+    private requestReceivedAt: number = null;
+
+    private commonMethods: VerificationMethod[] = [];
+    private _phase: Phase;
+    private _cancellingUserId: string;
+    private _verifier: VerificationBase<any, any>;
+
+    constructor(
+        public readonly channel: C,
+        private readonly verificationMethods: Map<VerificationMethod, typeof VerificationBase>,
+        private readonly client: MatrixClient,
+    ) {
+        super();
+        this.channel.request = this;
+        this.setPhase(PHASE_UNSENT, false);
    }

    /**
@@ -91,9 +131,9 @@ export class VerificationRequest extends EventEmitter {
     * @param {string} type the "symbolic" event type, as returned by the `getEventType` function on the channel.
     * @param {MatrixEvent} event the event to validate. Don't call getType() on it but use the `type` parameter instead.
     * @param {MatrixClient} client the client to get the current user and device id from
-     * @returns {bool} whether the event is valid and should be passed to handleEvent
+     * @returns {boolean} whether the event is valid and should be passed to handleEvent
     */
-    static validateEvent(type, event, client) {
+    public static validateEvent(type: string, event: MatrixEvent, client: MatrixClient): boolean {
        const content = event.getContent();

        if (!type || !type.startsWith(EVENT_PREFIX)) {
@@ -128,53 +168,53 @@ export class VerificationRequest extends EventEmitter {
        return true;
    }

-    get invalid() {
+    public get invalid(): boolean {
        return this.phase === PHASE_UNSENT;
    }

    /** returns whether the phase is PHASE_REQUESTED */
-    get requested() {
+    public get requested(): boolean {
        return this.phase === PHASE_REQUESTED;
    }

    /** returns whether the phase is PHASE_CANCELLED */
-    get cancelled() {
+    public get cancelled(): boolean {
        return this.phase === PHASE_CANCELLED;
    }

    /** returns whether the phase is PHASE_READY */
-    get ready() {
+    public get ready(): boolean {
        return this.phase === PHASE_READY;
    }

    /** returns whether the phase is PHASE_STARTED */
-    get started() {
+    public get started(): boolean {
        return this.phase === PHASE_STARTED;
    }

    /** returns whether the phase is PHASE_DONE */
-    get done() {
+    public get done(): boolean {
        return this.phase === PHASE_DONE;
    }

    /** once the phase is PHASE_STARTED (and !initiatedByMe) or PHASE_READY: common methods supported by both sides */
-    get methods() {
-        return this._commonMethods;
+    public get methods(): VerificationMethod[] {
+        return this.commonMethods;
    }

    /** the method picked in the .start event */
-    get chosenMethod() {
+    public get chosenMethod(): VerificationMethod {
        return this._chosenMethod;
    }

-    calculateEventTimeout(event) {
+    public calculateEventTimeout(event: MatrixEvent): number {
        let effectiveExpiresAt = this.channel.getTimestamp(event)
            + TIMEOUT_FROM_EVENT_TS;

-        if (this._requestReceivedAt && !this.initiatedByMe &&
+        if (this.requestReceivedAt && !this.initiatedByMe &&
            this.phase <= PHASE_REQUESTED
        ) {
-            const expiresAtByReceipt = this._requestReceivedAt
+            const expiresAtByReceipt = this.requestReceivedAt
                + TIMEOUT_FROM_EVENT_RECEIPT;
            effectiveExpiresAt = Math.min(effectiveExpiresAt, expiresAtByReceipt);
        }
@@ -183,8 +223,8 @@ export class VerificationRequest extends EventEmitter {
    }

    /** The current remaining amount of ms before the request should be automatically cancelled */
-    get timeout() {
-        const requestEvent = this._getEventByEither(REQUEST_TYPE);
+    public get timeout(): number {
+        const requestEvent = this.getEventByEither(REQUEST_TYPE);
        if (requestEvent) {
            return this.calculateEventTimeout(requestEvent);
        }
@@ -195,41 +235,41 @@ export class VerificationRequest extends EventEmitter {
     * The key verification request event.
     * @returns {MatrixEvent} The request event, or falsey if not found.
     */
-    get requestEvent() {
-        return this._getEventByEither(REQUEST_TYPE);
+    public get requestEvent(): MatrixEvent {
+        return this.getEventByEither(REQUEST_TYPE);
    }

    /** current phase of the request. Some properties might only be defined in a current phase. */
-    get phase() {
+    public get phase(): Phase {
        return this._phase;
    }

    /** The verifier to do the actual verification, once the method has been established. Only defined when the `phase` is PHASE_STARTED. */
-    get verifier() {
+    public get verifier(): VerificationBase<any, any> {
        return this._verifier;
    }

-    get canAccept() {
+    public get canAccept(): boolean {
        return this.phase < PHASE_READY && !this._accepting && !this._declining;
    }

-    get accepting() {
+    public get accepting(): boolean {
        return this._accepting;
    }

-    get declining() {
+    public get declining(): boolean {
        return this._declining;
    }

    /** whether this request has sent it's initial event and needs more events to complete */
-    get pending() {
+    public get pending(): boolean {
        return !this.observeOnly &&
            this._phase !== PHASE_DONE &&
            this._phase !== PHASE_CANCELLED;
    }

    /** Only set after a .ready if the other party can scan a QR code */
-    get qrCodeData() {
+    public get qrCodeData(): QRCodeData {
        return this._qrCodeData;
    }

@@ -239,19 +279,19 @@ export class VerificationRequest extends EventEmitter {
     *  For methods that need to be supported by both ends, use the `methods` property.
     *  @param {string} method the method to check
     *  @param {boolean} force to check even if the phase is not ready or started yet, internal usage
-     *  @return {bool} whether or not the other party said the supported the method */
-    otherPartySupportsMethod(method, force = false) {
+     *  @return {boolean} whether or not the other party said the supported the method */
+    public otherPartySupportsMethod(method: string, force = false): boolean {
        if (!force && !this.ready && !this.started) {
            return false;
        }
-        const theirMethodEvent = this._eventsByThem.get(REQUEST_TYPE) ||
-            this._eventsByThem.get(READY_TYPE);
+        const theirMethodEvent = this.eventsByThem.get(REQUEST_TYPE) ||
+            this.eventsByThem.get(READY_TYPE);
        if (!theirMethodEvent) {
            // if we started straight away with .start event,
            // we are assuming that the other side will support the
            // chosen method, so return true for that.
            if (this.started && this.initiatedByMe) {
-                const myStartEvent = this._eventsByUs.get(START_TYPE);
+                const myStartEvent = this.eventsByUs.get(START_TYPE);
                const content = myStartEvent && myStartEvent.getContent();
                const myStartMethod = content && content.method;
                return method == myStartMethod;
@@ -274,22 +314,22 @@ export class VerificationRequest extends EventEmitter {
     * For InRoomChannel, this is who sent the .request event.
     * For ToDeviceChannel, this is who sent the .start event
     */
-    get initiatedByMe() {
+    public get initiatedByMe(): boolean {
        // event created by us but no remote echo has been received yet
-        const noEventsYet = (this._eventsByUs.size + this._eventsByThem.size) === 0;
+        const noEventsYet = (this.eventsByUs.size + this.eventsByThem.size) === 0;
        if (this._phase === PHASE_UNSENT && noEventsYet) {
            return true;
        }
-        const hasMyRequest = this._eventsByUs.has(REQUEST_TYPE);
-        const hasTheirRequest = this._eventsByThem.has(REQUEST_TYPE);
+        const hasMyRequest = this.eventsByUs.has(REQUEST_TYPE);
+        const hasTheirRequest = this.eventsByThem.has(REQUEST_TYPE);
        if (hasMyRequest && !hasTheirRequest) {
            return true;
        }
        if (!hasMyRequest && hasTheirRequest) {
            return false;
        }
-        const hasMyStart = this._eventsByUs.has(START_TYPE);
-        const hasTheirStart = this._eventsByThem.has(START_TYPE);
+        const hasMyStart = this.eventsByUs.has(START_TYPE);
+        const hasTheirStart = this.eventsByThem.has(START_TYPE);
        if (hasMyStart && !hasTheirStart) {
            return true;
        }
@@ -297,39 +337,39 @@ export class VerificationRequest extends EventEmitter {
    }

    /** The id of the user that initiated the request */
-    get requestingUserId() {
+    public get requestingUserId(): string {
        if (this.initiatedByMe) {
-            return this._client.getUserId();
+            return this.client.getUserId();
        } else {
            return this.otherUserId;
        }
    }

    /** The id of the user that (will) receive(d) the request */
-    get receivingUserId() {
+    public get receivingUserId(): string {
        if (this.initiatedByMe) {
            return this.otherUserId;
        } else {
-            return this._client.getUserId();
+            return this.client.getUserId();
        }
    }

    /** The user id of the other party in this request */
-    get otherUserId() {
+    public get otherUserId(): string {
        return this.channel.userId;
    }

-    get isSelfVerification() {
-        return this._client.getUserId() === this.otherUserId;
+    public get isSelfVerification(): boolean {
+        return this.client.getUserId() === this.otherUserId;
    }

    /**
     * The id of the user that cancelled the request,
     * only defined when phase is PHASE_CANCELLED
     */
-    get cancellingUserId() {
-        const myCancel = this._eventsByUs.get(CANCEL_TYPE);
-        const theirCancel = this._eventsByThem.get(CANCEL_TYPE);
+    public get cancellingUserId(): string {
+        const myCancel = this.eventsByUs.get(CANCEL_TYPE);
+        const theirCancel = this.eventsByThem.get(CANCEL_TYPE);

        if (myCancel && (!theirCancel || myCancel.getId() < theirCancel.getId())) {
            return myCancel.getSender();
@@ -343,12 +383,12 @@ export class VerificationRequest extends EventEmitter {
    /**
     * The cancellation code e.g m.user which is responsible for cancelling this verification
     */
-    get cancellationCode() {
-        const ev = this._getEventByEither(CANCEL_TYPE);
+    public get cancellationCode(): string {
+        const ev = this.getEventByEither(CANCEL_TYPE);
        return ev ? ev.getContent().code : null;
    }

-    get observeOnly() {
+    public get observeOnly(): boolean {
        return this._observeOnly;
    }

@@ -359,11 +399,11 @@ export class VerificationRequest extends EventEmitter {
     * verification to when no specific device is specified.
     * @returns {{userId: *, deviceId: *}} The device information
     */
-    get targetDevice() {
+    public get targetDevice(): ITargetDevice {
        const theirFirstEvent =
-            this._eventsByThem.get(REQUEST_TYPE) ||
-            this._eventsByThem.get(READY_TYPE) ||
-            this._eventsByThem.get(START_TYPE);
+            this.eventsByThem.get(REQUEST_TYPE) ||
+            this.eventsByThem.get(READY_TYPE) ||
+            this.eventsByThem.get(START_TYPE);
        const theirFirstContent = theirFirstEvent.getContent();
        const fromDevice = theirFirstContent.from_device;
        return {
@@ -379,21 +419,23 @@ export class VerificationRequest extends EventEmitter {
     * @param {string?} targetDevice.deviceId the id of the device to direct this request to
     * @returns {VerifierBase} the verifier of the given method
     */
-    beginKeyVerification(method, targetDevice = null) {
+    public beginKeyVerification(
+        method: VerificationMethod,
+        targetDevice: ITargetDevice = null,
+    ): VerificationBase<any, any> {
        // need to allow also when unsent in case of to_device
        if (!this.observeOnly && !this._verifier) {
            const validStartPhase =
                this.phase === PHASE_REQUESTED ||
                this.phase === PHASE_READY ||
-                (this.phase === PHASE_UNSENT &&
-                    this.channel.constructor.canCreateRequest(START_TYPE));
+                (this.phase === PHASE_UNSENT && this.channel.canCreateRequest(START_TYPE));
            if (validStartPhase) {
                // when called on a request that was initiated with .request event
                // check the method is supported by both sides
-                if (this._commonMethods.length && !this._commonMethods.includes(method)) {
+                if (this.commonMethods.length && !this.commonMethods.includes(method)) {
                    throw newUnknownMethodError();
                }
-                this._verifier = this._createVerifier(method, null, targetDevice);
+                this._verifier = this.createVerifier(method, null, targetDevice);
                if (!this._verifier) {
                    throw newUnknownMethodError();
                }
@@ -407,9 +449,9 @@ export class VerificationRequest extends EventEmitter {
     * sends the initial .request event.
     * @returns {Promise} resolves when the event has been sent.
     */
-    async sendRequest() {
+    public async sendRequest(): Promise<void> {
        if (!this.observeOnly && this._phase === PHASE_UNSENT) {
-            const methods = [...this._verificationMethods.keys()];
+            const methods = [...this.verificationMethods.keys()];
            await this.channel.send(REQUEST_TYPE, { methods });
        }
    }
@@ -420,14 +462,14 @@ export class VerificationRequest extends EventEmitter {
     * @param {string?} error.code the error code to send the cancellation with
     * @returns {Promise} resolves when the event has been sent.
     */
-    async cancel({ reason = "User declined", code = "m.user" } = {}) {
+    public async cancel({ reason = "User declined", code = "m.user" } = {}): Promise<void> {
        if (!this.observeOnly && this._phase !== PHASE_CANCELLED) {
            this._declining = true;
-            this.emit("change");
+            this.emit(VerificationRequestEvent.Change);
            if (this._verifier) {
                return this._verifier.cancel(errorFactory(code, reason)());
            } else {
-                this._cancellingUserId = this._client.getUserId();
+                this._cancellingUserId = this.client.getUserId();
                await this.channel.send(CANCEL_TYPE, { code, reason });
            }
        }
@@ -437,11 +479,11 @@ export class VerificationRequest extends EventEmitter {
     * Accepts the request, sending a .ready event to the other party
     * @returns {Promise} resolves when the event has been sent.
     */
-    async accept() {
+    public async accept(): Promise<void> {
        if (!this.observeOnly && this.phase === PHASE_REQUESTED && !this.initiatedByMe) {
-            const methods = [...this._verificationMethods.keys()];
+            const methods = [...this.verificationMethods.keys()];
            this._accepting = true;
-            this.emit("change");
+            this.emit(VerificationRequestEvent.Change);
            await this.channel.send(READY_TYPE, { methods });
        }
    }
@@ -453,7 +495,7 @@ export class VerificationRequest extends EventEmitter {
     * @returns {Promise} that resolves once the callback returns true
     * @throws {Error} when the request is cancelled
     */
-    waitFor(fn) {
+    public waitFor(fn: (request: VerificationRequest) => boolean): Promise<VerificationRequest> {
        return new Promise((resolve, reject) => {
            const check = () => {
                let handled = false;
@@ -465,56 +507,56 @@ export class VerificationRequest extends EventEmitter {
                    handled = true;
                }
                if (handled) {
-                    this.off("change", check);
+                    this.off(VerificationRequestEvent.Change, check);
                }
                return handled;
            };
            if (!check()) {
-                this.on("change", check);
+                this.on(VerificationRequestEvent.Change, check);
            }
        });
    }

-    _setPhase(phase, notify = true) {
+    private setPhase(phase: Phase, notify = true): void {
        this._phase = phase;
        if (notify) {
-            this.emit("change");
+            this.emit(VerificationRequestEvent.Change);
        }
    }

-    _getEventByEither(type) {
-        return this._eventsByThem.get(type) || this._eventsByUs.get(type);
+    private getEventByEither(type: string): MatrixEvent {
+        return this.eventsByThem.get(type) || this.eventsByUs.get(type);
    }

-    _getEventBy(type, byThem) {
+    private getEventBy(type: string, byThem = false): MatrixEvent {
        if (byThem) {
-            return this._eventsByThem.get(type);
+            return this.eventsByThem.get(type);
        } else {
-            return this._eventsByUs.get(type);
+            return this.eventsByUs.get(type);
        }
    }

-    _calculatePhaseTransitions() {
-        const transitions = [{ phase: PHASE_UNSENT }];
+    private calculatePhaseTransitions(): ITransition[] {
+        const transitions: ITransition[] = [{ phase: PHASE_UNSENT }];
        const phase = () => transitions[transitions.length - 1].phase;

        // always pass by .request first to be sure channel.userId has been set
-        const hasRequestByThem = this._eventsByThem.has(REQUEST_TYPE);
-        const requestEvent = this._getEventBy(REQUEST_TYPE, hasRequestByThem);
+        const hasRequestByThem = this.eventsByThem.has(REQUEST_TYPE);
+        const requestEvent = this.getEventBy(REQUEST_TYPE, hasRequestByThem);
        if (requestEvent) {
            transitions.push({ phase: PHASE_REQUESTED, event: requestEvent });
        }

        const readyEvent =
-            requestEvent && this._getEventBy(READY_TYPE, !hasRequestByThem);
+            requestEvent && this.getEventBy(READY_TYPE, !hasRequestByThem);
        if (readyEvent && phase() === PHASE_REQUESTED) {
            transitions.push({ phase: PHASE_READY, event: readyEvent });
        }

        let startEvent;
        if (readyEvent || !requestEvent) {
-            const theirStartEvent = this._eventsByThem.get(START_TYPE);
-            const ourStartEvent = this._eventsByUs.get(START_TYPE);
+            const theirStartEvent = this.eventsByThem.get(START_TYPE);
+            const ourStartEvent = this.eventsByUs.get(START_TYPE);
            // any party can send .start after a .ready or unsent
            if (theirStartEvent && ourStartEvent) {
                startEvent = theirStartEvent.getSender() < ourStartEvent.getSender() ?
@@ -523,24 +565,22 @@ export class VerificationRequest extends EventEmitter {
                startEvent = theirStartEvent ? theirStartEvent : ourStartEvent;
            }
        } else {
-            startEvent = this._getEventBy(START_TYPE, !hasRequestByThem);
+            startEvent = this.getEventBy(START_TYPE, !hasRequestByThem);
        }
        if (startEvent) {
-            const fromRequestPhase = phase() === PHASE_REQUESTED &&
-                requestEvent.getSender() !== startEvent.getSender();
-            const fromUnsentPhase = phase() === PHASE_UNSENT &&
-                this.channel.constructor.canCreateRequest(START_TYPE);
+            const fromRequestPhase = phase() === PHASE_REQUESTED && requestEvent.getSender() !== startEvent.getSender();
+            const fromUnsentPhase = phase() === PHASE_UNSENT && this.channel.canCreateRequest(START_TYPE);
            if (fromRequestPhase || phase() === PHASE_READY || fromUnsentPhase) {
                transitions.push({ phase: PHASE_STARTED, event: startEvent });
            }
        }

-        const ourDoneEvent = this._eventsByUs.get(DONE_TYPE);
-        if (this._verifierHasFinished || (ourDoneEvent && phase() === PHASE_STARTED)) {
+        const ourDoneEvent = this.eventsByUs.get(DONE_TYPE);
+        if (this.verifierHasFinished || (ourDoneEvent && phase() === PHASE_STARTED)) {
            transitions.push({ phase: PHASE_DONE });
        }

-        const cancelEvent = this._getEventByEither(CANCEL_TYPE);
+        const cancelEvent = this.getEventByEither(CANCEL_TYPE);
        if ((this._cancelled || cancelEvent) && phase() !== PHASE_DONE) {
            transitions.push({ phase: PHASE_CANCELLED, event: cancelEvent });
            return transitions;
@@ -549,14 +589,16 @@ export class VerificationRequest extends EventEmitter {
        return transitions;
    }

-    _transitionToPhase(transition) {
+    private transitionToPhase(transition: ITransition): void {
        const { phase, event } = transition;
        // get common methods
        if (phase === PHASE_REQUESTED || phase === PHASE_READY) {
-            if (!this._wasSentByOwnDevice(event)) {
-                const content = event.getContent();
-                this._commonMethods =
-                    content.methods.filter(m => this._verificationMethods.has(m));
+            if (!this.wasSentByOwnDevice(event)) {
+                const content = event.getContent<{
+                    methods: string[];
+                }>();
+                this.commonMethods =
+                    content.methods.filter(m => this.verificationMethods.has(m));
            }
        }
        // detect if we're not a party in the request, and we should just observe
@@ -568,8 +610,8 @@ export class VerificationRequest extends EventEmitter {
            ) {
                if (
                    this.channel.receiveStartFromOtherDevices &&
-                    this._wasSentByOwnUser(event) &&
-                    !this._wasSentByOwnDevice(event)
+                    this.wasSentByOwnUser(event) &&
+                    !this.wasSentByOwnDevice(event)
                ) {
                    this._observeOnly = true;
                }
@@ -579,7 +621,7 @@ export class VerificationRequest extends EventEmitter {
        if (phase === PHASE_STARTED) {
            const { method } = event.getContent();
            if (!this._verifier && !this.observeOnly) {
-                this._verifier = this._createVerifier(method, event);
+                this._verifier = this.createVerifier(method, event);
                if (!this._verifier) {
                    this.cancel({
                        code: "m.unknown_method",
@@ -592,19 +634,19 @@ export class VerificationRequest extends EventEmitter {
        }
    }

-    _applyPhaseTransitions() {
-        const transitions = this._calculatePhaseTransitions();
+    private applyPhaseTransitions(): ITransition[] {
+        const transitions = this.calculatePhaseTransitions();
        const existingIdx = transitions.findIndex(t => t.phase === this.phase);
        // trim off phases we already went through, if any
        const newTransitions = transitions.slice(existingIdx + 1);
        // transition to all new phases
        for (const transition of newTransitions) {
-            this._transitionToPhase(transition);
+            this.transitionToPhase(transition);
        }
        return newTransitions;
    }

-    _isWinningStartRace(newEvent) {
+    private isWinningStartRace(newEvent: MatrixEvent): boolean {
        if (newEvent.getType() !== START_TYPE) {
            return false;
        }
@@ -620,13 +662,13 @@ export class VerificationRequest extends EventEmitter {
                const oldContent = oldEvent.getContent();
                oldRaceIdentifier = oldContent && oldContent.from_device;
            } else {
-                oldRaceIdentifier = this._client.getDeviceId();
+                oldRaceIdentifier = this.client.getDeviceId();
            }
        } else {
            if (oldEvent) {
                oldRaceIdentifier = oldEvent.getSender();
            } else {
-                oldRaceIdentifier = this._client.getUserId();
+                oldRaceIdentifier = this.client.getUserId();
            }
        }

@@ -640,13 +682,13 @@ export class VerificationRequest extends EventEmitter {
        return newRaceIdentifier < oldRaceIdentifier;
    }

-    hasEventId(eventId) {
-        for (const event of this._eventsByUs.values()) {
+    public hasEventId(eventId: string): boolean {
+        for (const event of this.eventsByUs.values()) {
            if (event.getId() === eventId) {
                return true;
            }
        }
-        for (const event of this._eventsByThem.values()) {
+        for (const event of this.eventsByThem.values()) {
            if (event.getId() === eventId) {
                return true;
            }
@@ -658,23 +700,29 @@ export class VerificationRequest extends EventEmitter {
     * Changes the state of the request and verifier in response to a key verification event.
     * @param {string} type the "symbolic" event type, as returned by the `getEventType` function on the channel.
     * @param {MatrixEvent} event the event to handle. Don't call getType() on it but use the `type` parameter instead.
-     * @param {bool} isLiveEvent whether this is an even received through sync or not
-     * @param {bool} isRemoteEcho whether this is the remote echo of an event sent by the same device
-     * @param {bool} isSentByUs whether this event is sent by a party that can accept and/or observe the request like one of our peers.
+     * @param {boolean} isLiveEvent whether this is an even received through sync or not
+     * @param {boolean} isRemoteEcho whether this is the remote echo of an event sent by the same device
+     * @param {boolean} isSentByUs whether this event is sent by a party that can accept and/or observe the request like one of our peers.
     *   For InRoomChannel this means any device for the syncing user. For ToDeviceChannel, just the syncing device.
-     * @returns {Promise} a promise that resolves when any requests as an anwser to the passed-in event are sent.
+     * @returns {Promise} a promise that resolves when any requests as an answer to the passed-in event are sent.
     */
-    async handleEvent(type, event, isLiveEvent, isRemoteEcho, isSentByUs) {
+    public async handleEvent(
+        type: string,
+        event: MatrixEvent,
+        isLiveEvent: boolean,
+        isRemoteEcho: boolean,
+        isSentByUs: boolean,
+    ): Promise<void> {
        // if reached phase cancelled or done, ignore anything else that comes
        if (this.done || this.cancelled) {
            return;
        }
        const wasObserveOnly = this._observeOnly;

-        this._adjustObserveOnly(event, isLiveEvent);
+        this.adjustObserveOnly(event, isLiveEvent);

        if (!this.observeOnly && !isRemoteEcho) {
-            if (await this._cancelOnError(type, event)) {
+            if (await this.cancelOnError(type, event)) {
                return;
            }
        }
@@ -685,27 +733,26 @@ export class VerificationRequest extends EventEmitter {
        // added here to prevent verification getting cancelled
        // when the server duplicates an event (https://github.com/matrix-org/synapse/issues/3365)
        const isDuplicateEvent = isSentByUs ?
-            this._eventsByUs.has(type) :
-            this._eventsByThem.has(type);
+            this.eventsByUs.has(type) :
+            this.eventsByThem.has(type);
        if (isDuplicateEvent) {
            return;
        }

        const oldPhase = this.phase;
-        this._addEvent(type, event, isSentByUs);
+        this.addEvent(type, event, isSentByUs);

        // this will create if needed the verifier so needs to happen before calling it
-        const newTransitions = this._applyPhaseTransitions();
+        const newTransitions = this.applyPhaseTransitions();
        try {
            // only pass events from the other side to the verifier,
            // no remote echos of our own events
            if (this._verifier && !this.observeOnly) {
-                const newEventWinsRace = this._isWinningStartRace(event);
+                const newEventWinsRace = this.isWinningStartRace(event);
                if (this._verifier.canSwitchStartEvent(event) && newEventWinsRace) {
                    this._verifier.switchStartEvent(event);
                } else if (!isRemoteEcho) {
-                    if (type === CANCEL_TYPE || (this._verifier.events
-                        && this._verifier.events.includes(type))) {
+                    if (type === CANCEL_TYPE || this._verifier.events?.includes(type)) {
                        this._verifier.handleEvent(event);
                    }
                }
@@ -722,18 +769,18 @@ export class VerificationRequest extends EventEmitter {
                    const shouldGenerateQrCode =
                        this.otherPartySupportsMethod(SCAN_QR_CODE_METHOD, true);
                    if (shouldGenerateQrCode) {
-                        this._qrCodeData = await QRCodeData.create(this, this._client);
+                        this._qrCodeData = await QRCodeData.create(this, this.client);
                    }
                }

                const lastTransition = newTransitions[newTransitions.length - 1];
                const { phase } = lastTransition;

-                this._setupTimeout(phase);
+                this.setupTimeout(phase);
                // set phase as last thing as this emits the "change" event
-                this._setPhase(phase);
+                this.setPhase(phase);
            } else if (this._observeOnly !== wasObserveOnly) {
-                this.emit("change");
+                this.emit(VerificationRequestEvent.Change);
            }
        } finally {
            // log events we processed so we can see from rageshakes what events were added to a request
@@ -748,26 +795,26 @@ export class VerificationRequest extends EventEmitter {
        }
    }

-    _setupTimeout(phase) {
-        const shouldTimeout = !this._timeoutTimer && !this.observeOnly &&
+    private setupTimeout(phase: Phase): void {
+        const shouldTimeout = !this.timeoutTimer && !this.observeOnly &&
            phase === PHASE_REQUESTED;

        if (shouldTimeout) {
-            this._timeoutTimer = setTimeout(this._cancelOnTimeout, this.timeout);
+            this.timeoutTimer = setTimeout(this.cancelOnTimeout, this.timeout);
        }
-        if (this._timeoutTimer) {
+        if (this.timeoutTimer) {
            const shouldClear = phase === PHASE_STARTED ||
                phase === PHASE_READY ||
                phase === PHASE_DONE ||
                phase === PHASE_CANCELLED;
            if (shouldClear) {
-                clearTimeout(this._timeoutTimer);
-                this._timeoutTimer = null;
+                clearTimeout(this.timeoutTimer);
+                this.timeoutTimer = null;
            }
        }
    }

-    _cancelOnTimeout = () => {
+    private cancelOnTimeout = () => {
        try {
            if (this.initiatedByMe) {
                this.cancel({
@@ -785,10 +832,10 @@ export class VerificationRequest extends EventEmitter {
        }
    };

-    async _cancelOnError(type, event) {
+    private async cancelOnError(type: string, event: MatrixEvent): Promise<boolean> {
        if (type === START_TYPE) {
            const method = event.getContent().method;
-            if (!this._verificationMethods.has(method)) {
+            if (!this.verificationMethods.has(method)) {
                await this.cancel(errorFromEvent(newUnknownMethodError()));
                return true;
            }
@@ -811,7 +858,7 @@ export class VerificationRequest extends EventEmitter {
        return false;
    }

-    _adjustObserveOnly(event, isLiveEvent) {
+    private adjustObserveOnly(event: MatrixEvent, isLiveEvent = false): void {
        // don't send out events for historical requests
        if (!isLiveEvent) {
            this._observeOnly = true;
@@ -821,83 +868,80 @@ export class VerificationRequest extends EventEmitter {
        }
    }

-    _addEvent(type, event, isSentByUs) {
+    private addEvent(type: string, event: MatrixEvent, isSentByUs = false): void {
        if (isSentByUs) {
-            this._eventsByUs.set(type, event);
+            this.eventsByUs.set(type, event);
        } else {
-            this._eventsByThem.set(type, event);
+            this.eventsByThem.set(type, event);
        }

        // once we know the userId of the other party (from the .request event)
-        // see if any event by anyone else crept into this._eventsByThem
+        // see if any event by anyone else crept into this.eventsByThem
        if (type === REQUEST_TYPE) {
-            for (const [type, event] of this._eventsByThem.entries()) {
+            for (const [type, event] of this.eventsByThem.entries()) {
                if (event.getSender() !== this.otherUserId) {
-                    this._eventsByThem.delete(type);
+                    this.eventsByThem.delete(type);
                }
            }
            // also remember when we received the request event
-            this._requestReceivedAt = Date.now();
+            this.requestReceivedAt = Date.now();
        }
    }

-    _createVerifier(method, startEvent = null, targetDevice = null) {
+    private createVerifier(
+        method: VerificationMethod,
+        startEvent: MatrixEvent = null,
+        targetDevice: ITargetDevice = null,
+    ): VerificationBase<any, any> {
        if (!targetDevice) {
            targetDevice = this.targetDevice;
        }
        const { userId, deviceId } = targetDevice;

-        const VerifierCtor = this._verificationMethods.get(method);
+        const VerifierCtor = this.verificationMethods.get(method);
        if (!VerifierCtor) {
            logger.warn("could not find verifier constructor for method", method);
            return;
        }
-        return new VerifierCtor(
-            this.channel,
-            this._client,
-            userId,
-            deviceId,
-            startEvent,
-            this,
-        );
+        return new VerifierCtor(this.channel, this.client, userId, deviceId, startEvent, this);
    }

-    _wasSentByOwnUser(event) {
-        return event.getSender() === this._client.getUserId();
+    private wasSentByOwnUser(event: MatrixEvent): boolean {
+        return event.getSender() === this.client.getUserId();
    }

    // only for .request, .ready or .start
-    _wasSentByOwnDevice(event) {
-        if (!this._wasSentByOwnUser(event)) {
+    private wasSentByOwnDevice(event: MatrixEvent): boolean {
+        if (!this.wasSentByOwnUser(event)) {
            return false;
        }
        const content = event.getContent();
-        if (!content || content.from_device !== this._client.getDeviceId()) {
+        if (!content || content.from_device !== this.client.getDeviceId()) {
            return false;
        }
        return true;
    }

-    onVerifierCancelled() {
+    public onVerifierCancelled(): void {
        this._cancelled = true;
        // move to cancelled phase
-        const newTransitions = this._applyPhaseTransitions();
+        const newTransitions = this.applyPhaseTransitions();
        if (newTransitions.length) {
-            this._setPhase(newTransitions[newTransitions.length - 1].phase);
+            this.setPhase(newTransitions[newTransitions.length - 1].phase);
        }
    }

-    onVerifierFinished() {
+    public onVerifierFinished(): void {
        this.channel.send("m.key.verification.done", {});
-        this._verifierHasFinished = true;
+        this.verifierHasFinished = true;
        // move to .done phase
-        const newTransitions = this._applyPhaseTransitions();
+        const newTransitions = this.applyPhaseTransitions();
        if (newTransitions.length) {
-            this._setPhase(newTransitions[newTransitions.length - 1].phase);
+            this.setPhase(newTransitions[newTransitions.length - 1].phase);
        }
    }

-    getEventFromOtherParty(type) {
-        return this._eventsByThem.get(type);
+    public getEventFromOtherParty(type: string): MatrixEvent {
+        return this.eventsByThem.get(type);
    }
 }
@@ -15,7 +15,7 @@ limitations under the License.
 */

 import { MatrixClient } from "./client";
-import { IEvent, MatrixEvent } from "./models/event";
+import { IEvent, MatrixEvent, MatrixEventEvent } from "./models/event";

 export type EventMapper = (obj: Partial<IEvent>) => MatrixEvent;

@@ -30,10 +30,16 @@ export function eventMapperFor(client: MatrixClient, options: MapperOpts): Event

    function mapper(plainOldJsObject: Partial<IEvent>) {
        const event = new MatrixEvent(plainOldJsObject);
+
+        const room = client.getRoom(event.getRoomId());
+        if (room?.threads.has(event.getId())) {
+            event.setThread(room.threads.get(event.getId()));
+        }
+
        if (event.isEncrypted()) {
            if (!preventReEmit) {
                client.reEmitter.reEmit(event, [
-                    "Event.decrypted",
+                    MatrixEventEvent.Decrypted,
                ]);
            }
            if (decrypt) {
@@ -41,7 +47,10 @@ export function eventMapperFor(client: MatrixClient, options: MapperOpts): Event
            }
        }
        if (!preventReEmit) {
-            client.reEmitter.reEmit(event, ["Event.replaced"]);
+            client.reEmitter.reEmit(event, [
+                MatrixEventEvent.Replaced,
+                MatrixEventEvent.VisibilityChange,
+            ]);
        }
        return event;
    }
@@ -14,6 +14,11 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

+import { RelationType } from "./@types/event";
+import {
+    UNSTABLE_FILTER_RELATED_BY_REL_TYPES,
+    UNSTABLE_FILTER_RELATED_BY_SENDERS,
+} from "./filter";
 import { MatrixEvent } from "./models/event";

 /**
@@ -46,6 +51,8 @@ export interface IFilterComponent {
    not_senders?: string[];
    contains_url?: boolean;
    limit?: number;
+    [UNSTABLE_FILTER_RELATED_BY_SENDERS.name]?: string[];
+    [UNSTABLE_FILTER_RELATED_BY_REL_TYPES.name]?: Array<RelationType | string>;
 }
 /* eslint-enable camelcase */

@@ -61,7 +68,7 @@ export interface IFilterComponent {
 * @param {Object} filterJson the definition of this filter JSON, e.g. { 'contains_url': true }
 */
 export class FilterComponent {
-    constructor(private filterJson: IFilterComponent) {}
+    constructor(private filterJson: IFilterComponent, public readonly userId?: string) {}

    /**
     * Checks with the filter component matches the given event
@@ -69,11 +76,25 @@ export class FilterComponent {
     * @return {boolean} true if the event matches the filter
     */
    public check(event: MatrixEvent): boolean {
+        const bundledRelationships = event.getUnsigned()?.["m.relations"] || {};
+        const relations: Array<string | RelationType> = Object.keys(bundledRelationships);
+        // Relation senders allows in theory a look-up of any senders
+        // however clients can only know about the current user participation status
+        // as sending a whole list of participants could be proven problematic in terms
+        // of performance
+        // This should be improved when bundled relationships solve that problem
+        const relationSenders = [];
+        if (this.userId && bundledRelationships?.[RelationType.Thread]?.current_user_participated) {
+            relationSenders.push(this.userId);
+        }
+
        return this.checkFields(
            event.getRoomId(),
            event.getSender(),
            event.getType(),
            event.getContent() ? event.getContent().url !== undefined : false,
+            relations,
+            relationSenders,
        );
    }

@@ -89,6 +110,8 @@ export class FilterComponent {
            senders: this.filterJson.senders || null,
            not_senders: this.filterJson.not_senders || [],
            contains_url: this.filterJson.contains_url || null,
+            [UNSTABLE_FILTER_RELATED_BY_SENDERS.name]: UNSTABLE_FILTER_RELATED_BY_SENDERS.findIn(this.filterJson),
+            [UNSTABLE_FILTER_RELATED_BY_REL_TYPES.name]: UNSTABLE_FILTER_RELATED_BY_REL_TYPES.findIn(this.filterJson),
        };
    }

@@ -98,9 +121,18 @@ export class FilterComponent {
     * @param {String} sender        the sender of the event being checked
     * @param {String} eventType     the type of the event being checked
     * @param {boolean} containsUrl  whether the event contains a content.url field
+     * @param {boolean} relationTypes  whether has aggregated relation of the given type
+     * @param {boolean} relationSenders whether one of the relation is sent by the user listed
     * @return {boolean} true if the event fields match the filter
     */
-    private checkFields(roomId: string, sender: string, eventType: string, containsUrl: boolean): boolean {
+    private checkFields(
+        roomId: string,
+        sender: string,
+        eventType: string,
+        containsUrl: boolean,
+        relationTypes: Array<RelationType | string>,
+        relationSenders: string[],
+    ): boolean {
        const literalKeys = {
            "rooms": function(v: string): boolean {
                return roomId === v;
@@ -133,15 +165,35 @@ export class FilterComponent {
            return false;
        }

+        const relationTypesFilter = this.filterJson[UNSTABLE_FILTER_RELATED_BY_REL_TYPES.name];
+        if (relationTypesFilter !== undefined) {
+            if (!this.arrayMatchesFilter(relationTypesFilter, relationTypes)) {
+                return false;
+            }
+        }
+
+        const relationSendersFilter = this.filterJson[UNSTABLE_FILTER_RELATED_BY_SENDERS.name];
+        if (relationSendersFilter !== undefined) {
+            if (!this.arrayMatchesFilter(relationSendersFilter, relationSenders)) {
+                return false;
+            }
+        }
+
        return true;
    }

+    private arrayMatchesFilter(filter: any[], values: any[]): boolean {
+        return values.length > 0 && values.every(value => {
+            return filter.includes(value);
+        });
+    }
+
    /**
     * Filters a list of events down to those which match this filter component
     * @param {MatrixEvent[]} events  Events to be checked against the filter component
     * @return {MatrixEvent[]} events which matched the filter component
     */
-    filter(events: MatrixEvent[]): MatrixEvent[] {
+    public filter(events: MatrixEvent[]): MatrixEvent[] {
        return events.filter(this.check, this);
    }

@@ -150,7 +202,7 @@ export class FilterComponent {
     * 10 if none is otherwise specified. Cargo-culted from Synapse.
     * @return {Number} the limit for this filter component.
     */
-    limit(): number {
+    public limit(): number {
        return this.filterJson.limit !== undefined ? this.filterJson.limit : 10;
    }
 }
@@ -18,8 +18,23 @@ limitations under the License.
 * @module filter
 */

+import {
+    EventType,
+    RelationType,
+} from "./@types/event";
 import { FilterComponent, IFilterComponent } from "./filter-component";
 import { MatrixEvent } from "./models/event";
+import { UnstableValue } from "./NamespacedValue";
+
+export const UNSTABLE_FILTER_RELATED_BY_SENDERS = new UnstableValue(
+    "related_by_senders",
+    "io.element.relation_senders",
+);
+
+export const UNSTABLE_FILTER_RELATED_BY_REL_TYPES = new UnstableValue(
+    "related_by_rel_types",
+    "io.element.relation_types",
+);

 /**
 * @param {Object} obj
@@ -50,6 +65,9 @@ export interface IFilterDefinition {
 export interface IRoomEventFilter extends IFilterComponent {
    lazy_load_members?: boolean;
    include_redundant_members?: boolean;
+    types?: Array<EventType | string>;
+    [UNSTABLE_FILTER_RELATED_BY_REL_TYPES.name]?: Array<RelationType | string>;
+    [UNSTABLE_FILTER_RELATED_BY_SENDERS.name]?: string[];
 }

 interface IStateFilter extends IRoomEventFilter {}
@@ -167,8 +185,8 @@ export class Filter {
            }
        }

-        this.roomFilter = new FilterComponent(roomFilterFields);
-        this.roomTimelineFilter = new FilterComponent(roomFilterJson?.timeline || {});
+        this.roomFilter = new FilterComponent(roomFilterFields, this.userId);
+        this.roomTimelineFilter = new FilterComponent(roomFilterJson?.timeline || {}, this.userId);

        // don't bother porting this from synapse yet:
        // this._room_state_filter =
@@ -1,6 +1,6 @@
 /*
 Copyright 2015, 2016 OpenMarket Ltd
-Copyright 2019 The Matrix.org Foundation C.I.C.
+Copyright 2019 - 2021 The Matrix.org Foundation C.I.C.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -20,14 +20,21 @@ limitations under the License.
 * @module http-api
 */

-import { parse as parseContentType } from "content-type";
-import * as utils from "./utils";
-import { logger } from './logger';
+import { parse as parseContentType, ParsedMediaType } from "content-type";

+import type { IncomingHttpHeaders, IncomingMessage } from "http";
+import type { Request as _Request, CoreOptions } from "request";
 // we use our own implementation of setTimeout, so that if we get suspended in
 // the middle of a /sync, we cancel the sync as soon as we awake, rather than
 // waiting for the delay to elapse.
 import * as callbacks from "./realtime-callbacks";
+import { IUploadOpts } from "./@types/requests";
+import { IAbortablePromise, IUsageLimit } from "./@types/partials";
+import { IDeferred } from "./utils";
+import { Callback } from "./client";
+import * as utils from "./utils";
+import { logger } from './logger';
+import { TypedEventEmitter } from "./models/typed-event-emitter";

 /*
 TODO:
@@ -40,6 +47,11 @@ TODO:
 */
 export const PREFIX_R0 = "/_matrix/client/r0";

+/**
+ * A constant representing the URI path for release v1 of the Client-Server HTTP API.
+ */
+export const PREFIX_V1 = "/_matrix/client/v1";
+
 /**
 * A constant representing the URI path for as-yet unspecified Client-Server HTTP APIs.
 */
@@ -61,10 +73,111 @@ export const PREFIX_IDENTITY_V2 = "/_matrix/identity/v2";
 */
 export const PREFIX_MEDIA_R0 = "/_matrix/media/r0";

+type RequestProps = "method"
+    | "withCredentials"
+    | "json"
+    | "headers"
+    | "qs"
+    | "body"
+    | "qsStringifyOptions"
+    | "useQuerystring"
+    | "timeout";
+
+export interface IHttpOpts {
+    baseUrl: string;
+    idBaseUrl?: string;
+    prefix: string;
+    onlyData: boolean;
+    accessToken?: string;
+    extraParams?: Record<string, string>;
+    localTimeoutMs?: number;
+    useAuthorizationHeader?: boolean;
+    request(opts: Pick<CoreOptions, RequestProps> & {
+        uri: string;
+        method: Method;
+        // eslint-disable-next-line camelcase
+        _matrix_opts: IHttpOpts;
+    }, callback: RequestCallback): IRequest;
+}
+
+interface IRequest extends _Request {
+    onprogress?(e: unknown): void;
+}
+
+interface IRequestOpts<T> {
+    prefix?: string;
+    localTimeoutMs?: number;
+    headers?: Record<string, string>;
+    json?: boolean; // defaults to true
+    qsStringifyOptions?: CoreOptions["qsStringifyOptions"];
+    bodyParser?(body: string): T;
+
+    // Set to true to prevent the request function from emitting
+    // a Session.logged_out event. This is intended for use on
+    // endpoints where M_UNKNOWN_TOKEN is a valid/notable error
+    // response, such as with token refreshes.
+    inhibitLogoutEmit?: boolean;
+}
+
+export interface IUpload {
+    loaded: number;
+    total: number;
+    promise: IAbortablePromise<unknown>;
+}
+
+interface IContentUri {
+    base: string;
+    path: string;
+    params: {
+        // eslint-disable-next-line camelcase
+        access_token: string;
+    };
+}
+
+type ResponseType<T, O extends IRequestOpts<T> | void = void> =
+    O extends { bodyParser: (body: string) => T } ? T :
+    O extends { json: false } ? string :
+    T;
+
+interface IUploadResponse {
+    // eslint-disable-next-line camelcase
+    content_uri: string;
+}
+
+// This type's defaults only work for the Browser
+// in the Browser we default rawResponse = false & onlyContentUri = true
+// in Node we default rawResponse = true & onlyContentUri = false
+export type UploadContentResponseType<O extends IUploadOpts> =
+    O extends undefined ? string :
+    O extends { rawResponse: true } ? string :
+    O extends { onlyContentUri: true } ? string :
+    O extends { rawResponse: false } ? IUploadResponse :
+    O extends { onlyContentUri: false } ? IUploadResponse :
+    string;
+
+export enum Method {
+    Get = "GET",
+    Put = "PUT",
+    Post = "POST",
+    Delete = "DELETE",
+}
+
+export type FileType = Document | XMLHttpRequestBodyInit;
+
+export enum HttpApiEvent {
+    SessionLoggedOut = "Session.logged_out",
+    NoConsent = "no_consent",
+}
+
+export type HttpApiEventHandlerMap = {
+    [HttpApiEvent.SessionLoggedOut]: (err: MatrixError) => void;
+    [HttpApiEvent.NoConsent]: (message: string, consentUri: string) => void;
+};
+
 /**
 * Construct a MatrixHttpApi.
 * @constructor
- * @param {EventEmitter} event_emitter The event emitter to use for emitting events
+ * @param {EventEmitter} eventEmitter The event emitter to use for emitting events
 * @param {Object} opts The options to use for this HTTP API.
 * @param {string} opts.baseUrl Required. The base client-server URL e.g.
 * 'http://localhost:8008'.
@@ -77,7 +190,7 @@ export const PREFIX_MEDIA_R0 = "/_matrix/media/r0";
 * response (e.g. the parsed HTTP body). If false, requests will return an
 * object with the properties <tt>code</tt>, <tt>headers</tt> and <tt>data</tt>.
 *
- * @param {string} opts.accessToken The access_token to send with requests. Can be
+ * @param {string=} opts.accessToken The access_token to send with requests. Can be
 * null to not send an access token.
 * @param {Object=} opts.extraParams Optional. Extra query parameters to send on
 * requests.
@@ -86,39 +199,40 @@ export const PREFIX_MEDIA_R0 = "/_matrix/media/r0";
 * @param {boolean} [opts.useAuthorizationHeader = false] Set to true to use
 * Authorization header instead of query param to send the access token to the server.
 */
-export function MatrixHttpApi(event_emitter, opts) {
-    utils.checkObjectHasKeys(opts, ["baseUrl", "request", "prefix"]);
-    opts.onlyData = opts.onlyData || false;
-    this.event_emitter = event_emitter;
-    this.opts = opts;
-    this.useAuthorizationHeader = Boolean(opts.useAuthorizationHeader);
-    this.uploads = [];
-}
+export class MatrixHttpApi {
+    private uploads: IUpload[] = [];
+
+    constructor(
+        private eventEmitter: TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>,
+        public readonly opts: IHttpOpts,
+    ) {
+        utils.checkObjectHasKeys(opts, ["baseUrl", "request", "prefix"]);
+        opts.onlyData = !!opts.onlyData;
+        opts.useAuthorizationHeader = !!opts.useAuthorizationHeader;
+    }

-MatrixHttpApi.prototype = {
    /**
-     * Sets the baase URL for the identity server
+     * Sets the base URL for the identity server
     * @param {string} url The new base url
     */
-    setIdBaseUrl: function(url) {
+    public setIdBaseUrl(url: string): void {
        this.opts.idBaseUrl = url;
-    },
+    }

    /**
     * Get the content repository url with query parameters.
     * @return {Object} An object with a 'base', 'path' and 'params' for base URL,
     *          path and query parameters respectively.
     */
-    getContentUri: function() {
-        const params = {
-            access_token: this.opts.accessToken,
-        };
+    public getContentUri(): IContentUri {
        return {
            base: this.opts.baseUrl,
            path: "/_matrix/media/r0/upload",
-            params: params,
+            params: {
+                access_token: this.opts.accessToken,
+            },
        };
-    },
+    }

    /**
     * Upload content to the homeserver
@@ -160,14 +274,17 @@ MatrixHttpApi.prototype = {
     *    determined by this.opts.onlyData, opts.rawResponse, and
     *    opts.onlyContentUri.  Rejects with an error (usually a MatrixError).
     */
-    uploadContent: function(file, opts) {
+    public uploadContent<O extends IUploadOpts>(
+        file: FileType,
+        opts?: O,
+    ): IAbortablePromise<UploadContentResponseType<O>> {
        if (utils.isFunction(opts)) {
-            // opts used to be callback
+            // opts used to be callback, backwards compatibility
            opts = {
-                callback: opts,
-            };
-        } else if (opts === undefined) {
-            opts = {};
+                callback: opts as unknown as IUploadOpts["callback"],
+            } as O;
+        } else if (!opts) {
+            opts = {} as O;
        }

        // default opts.includeFilename to true (ignoring falsey values)
@@ -175,8 +292,8 @@ MatrixHttpApi.prototype = {

        // if the file doesn't have a mime type, use a default since
        // the HS errors if we don't supply one.
-        const contentType = opts.type || file.type || 'application/octet-stream';
-        const fileName = opts.name || file.name;
+        const contentType = opts.type || (file as File).type || 'application/octet-stream';
+        const fileName = opts.name || (file as File).name;

        // We used to recommend setting file.stream to the thing to upload on
        // Node.js. As of 2019-06-11, this is still in widespread use in various
@@ -185,13 +302,14 @@ MatrixHttpApi.prototype = {
        // the browser now define a `stream` method, which leads to trouble
        // here, so we also check the type of `stream`.
        let body = file;
-        if (body.stream && typeof body.stream !== "function") {
+        const bodyStream = (body as File | Blob).stream; // this type is wrong but for legacy reasons is good enough
+        if (bodyStream && typeof bodyStream !== "function") {
            logger.warn(
                "Using `file.stream` as the content to upload. Future " +
                "versions of the js-sdk will change this to expect `file` to " +
                "be the content directly.",
            );
-            body = body.stream;
+            body = bodyStream;
        }

        // backwards-compatibility hacks where we used to do different things
@@ -234,8 +352,8 @@ MatrixHttpApi.prototype = {
        // (browser-request doesn't support progress either, which is also kind
        // of important here)

-        const upload = { loaded: 0, total: 0 };
-        let promise;
+        const upload = { loaded: 0, total: 0 } as IUpload;
+        let promise: IAbortablePromise<UploadContentResponseType<O>>;

        // XMLHttpRequest doesn't parse JSON for us. request normally does, but
        // we're setting opts.json=false so that it doesn't JSON-encode the
@@ -243,7 +361,7 @@ MatrixHttpApi.prototype = {
        // way, we have to JSON-parse the response ourselves.
        let bodyParser = null;
        if (!rawResponse) {
-            bodyParser = function(rawBody) {
+            bodyParser = function(rawBody: string) {
                let body = JSON.parse(rawBody);
                if (onlyContentUri) {
                    body = body.content_uri;
@@ -256,25 +374,23 @@ MatrixHttpApi.prototype = {
        }

        if (global.XMLHttpRequest) {
-            const defer = utils.defer();
+            const defer = utils.defer<UploadContentResponseType<O>>();
            const xhr = new global.XMLHttpRequest();
-            upload.xhr = xhr;
            const cb = requestCallback(defer, opts.callback, this.opts.onlyData);

-            const timeout_fn = function() {
+            const timeoutFn = function() {
                xhr.abort();
                cb(new Error('Timeout'));
            };

-            // set an initial timeout of 30s; we'll advance it each time we get
-            // a progress notification
-            xhr.timeout_timer = callbacks.setTimeout(timeout_fn, 30000);
+            // set an initial timeout of 30s; we'll advance it each time we get a progress notification
+            let timeoutTimer = callbacks.setTimeout(timeoutFn, 30000);

            xhr.onreadystatechange = function() {
-                let resp;
+                let resp: string;
                switch (xhr.readyState) {
                    case global.XMLHttpRequest.DONE:
-                        callbacks.clearTimeout(xhr.timeout_timer);
+                        callbacks.clearTimeout(timeoutTimer);
                        try {
                            if (xhr.status === 0) {
                                throw new AbortError();
@@ -296,10 +412,10 @@ MatrixHttpApi.prototype = {
                }
            };
            xhr.upload.addEventListener("progress", function(ev) {
-                callbacks.clearTimeout(xhr.timeout_timer);
+                callbacks.clearTimeout(timeoutTimer);
                upload.loaded = ev.loaded;
                upload.total = ev.total;
-                xhr.timeout_timer = callbacks.setTimeout(timeout_fn, 30000);
+                timeoutTimer = callbacks.setTimeout(timeoutFn, 30000);
                if (opts.progressHandler) {
                    opts.progressHandler({
                        loaded: ev.loaded,
@@ -315,9 +431,8 @@ MatrixHttpApi.prototype = {
                queryArgs.push("filename=" + encodeURIComponent(fileName));
            }

-            if (!this.useAuthorizationHeader) {
-                queryArgs.push("access_token="
-                    + encodeURIComponent(this.opts.accessToken));
+            if (!this.opts.useAuthorizationHeader) {
+                queryArgs.push("access_token=" + encodeURIComponent(this.opts.accessToken));
            }

            if (queryArgs.length > 0) {
@@ -325,73 +440,79 @@ MatrixHttpApi.prototype = {
            }

            xhr.open("POST", url);
-            if (this.useAuthorizationHeader) {
+            if (this.opts.useAuthorizationHeader) {
                xhr.setRequestHeader("Authorization", "Bearer " + this.opts.accessToken);
            }
            xhr.setRequestHeader("Content-Type", contentType);
            xhr.send(body);
-            promise = defer.promise;
+            promise = defer.promise as IAbortablePromise<UploadContentResponseType<O>>;

-            // dirty hack (as per _request) to allow the upload to be cancelled.
+            // dirty hack (as per doRequest) to allow the upload to be cancelled.
            promise.abort = xhr.abort.bind(xhr);
        } else {
-            const queryParams = {};
+            const queryParams: Record<string, string> = {};

            if (includeFilename && fileName) {
                queryParams.filename = fileName;
            }

+            const headers: Record<string, string> = { "Content-Type": contentType };
+
+            // authedRequest uses `request` which is no longer maintained.
+            // `request` has a bug where if the body is zero bytes then you get an error: `Argument error, options.body`.
+            // See https://github.com/request/request/issues/920
+            // if body looks like a byte array and empty then set the Content-Length explicitly as a workaround:
+            if ((body as unknown as ArrayLike<number>).length === 0) {
+                headers["Content-Length"] = "0";
+            }
+
            promise = this.authedRequest(
-                opts.callback, "POST", "/upload", queryParams, body, {
+                opts.callback, Method.Post, "/upload", queryParams, body, {
                    prefix: "/_matrix/media/r0",
-                    headers: { "Content-Type": contentType },
+                    headers,
                    json: false,
-                    bodyParser: bodyParser,
+                    bodyParser,
                },
            );
        }

-        const self = this;
-
        // remove the upload from the list on completion
-        const promise0 = promise.finally(function() {
-            for (let i = 0; i < self.uploads.length; ++i) {
-                if (self.uploads[i] === upload) {
-                    self.uploads.splice(i, 1);
+        upload.promise = promise.finally(() => {
+            for (let i = 0; i < this.uploads.length; ++i) {
+                if (this.uploads[i] === upload) {
+                    this.uploads.splice(i, 1);
                    return;
                }
            }
-        });
+        }) as IAbortablePromise<UploadContentResponseType<O>>;

        // copy our dirty abort() method to the new promise
-        promise0.abort = promise.abort;
-
-        upload.promise = promise0;
+        upload.promise.abort = promise.abort;
        this.uploads.push(upload);

-        return promise0;
-    },
+        return upload.promise as IAbortablePromise<UploadContentResponseType<O>>;
+    }

-    cancelUpload: function(promise) {
+    public cancelUpload(promise: IAbortablePromise<unknown>): boolean {
        if (promise.abort) {
            promise.abort();
            return true;
        }
        return false;
-    },
+    }

-    getCurrentUploads: function() {
+    public getCurrentUploads(): IUpload[] {
        return this.uploads;
-    },
+    }

-    idServerRequest: function(
-        callback,
-        method,
-        path,
-        params,
-        prefix,
-        accessToken,
-    ) {
+    public idServerRequest<T>(
+        callback: Callback<T>,
+        method: Method,
+        path: string,
+        params: Record<string, string | string[]>,
+        prefix: string,
+        accessToken: string,
+    ): Promise<T> {
        if (!this.opts.idBaseUrl) {
            throw new Error("No identity server base URL set");
        }
@@ -406,28 +527,27 @@ MatrixHttpApi.prototype = {

        const opts = {
            uri: fullUri,
-            method: method,
+            method,
            withCredentials: false,
            json: true, // we want a JSON response if we can
            _matrix_opts: this.opts,
            headers: {},
-        };
-        if (method === 'GET') {
+        } as Parameters<IHttpOpts["request"]>[0];
+
+        if (method === Method.Get) {
            opts.qs = params;
        } else if (typeof params === "object") {
            opts.json = params;
        }
+
        if (accessToken) {
            opts.headers['Authorization'] = `Bearer ${accessToken}`;
        }

-        const defer = utils.defer();
-        this.opts.request(
-            opts,
-            requestCallback(defer, callback, this.opts.onlyData),
-        );
+        const defer = utils.defer<T>();
+        this.opts.request(opts, requestCallback(defer, callback, this.opts.onlyData));
        return defer.promise;
-    },
+    }

    /**
     * Perform an authorised request to the homeserver.
@@ -448,7 +568,7 @@ MatrixHttpApi.prototype = {
     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
     * timing out the request. If not specified, there is no timeout.
     *
-     * @param {sting=} opts.prefix The full prefix to use e.g.
+     * @param {string=} opts.prefix The full prefix to use e.g.
     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
     *
     * @param {Object=} opts.headers map of additional request headers
@@ -460,56 +580,52 @@ MatrixHttpApi.prototype = {
     * @return {module:http-api.MatrixError} Rejects with an error if a problem
     * occurred. This includes network problems and Matrix-specific error JSON.
     */
-    authedRequest: function(callback, method, path, queryParams, data, opts) {
-        if (!queryParams) {
-            queryParams = {};
-        }
-        if (this.useAuthorizationHeader) {
-            if (isFinite(opts)) {
+    public authedRequest<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
+        callback: Callback<T>,
+        method: Method,
+        path: string,
+        queryParams?: Record<string, string | string[]>,
+        data?: CoreOptions["body"],
+        opts?: O | number, // number is legacy
+    ): IAbortablePromise<ResponseType<T, O>> {
+        if (!queryParams) queryParams = {};
+        let requestOpts = (opts || {}) as O;
+
+        if (this.opts.useAuthorizationHeader) {
+            if (isFinite(opts as number)) {
                // opts used to be localTimeoutMs
-                opts = {
-                    localTimeoutMs: opts,
-                };
+                requestOpts = {
+                    localTimeoutMs: opts as number,
+                } as O;
            }
-            if (!opts) {
-                opts = {};
+
+            if (!requestOpts.headers) {
+                requestOpts.headers = {};
            }
-            if (!opts.headers) {
-                opts.headers = {};
-            }
-            if (!opts.headers.Authorization) {
-                opts.headers.Authorization = "Bearer " + this.opts.accessToken;
+            if (!requestOpts.headers.Authorization) {
+                requestOpts.headers.Authorization = "Bearer " + this.opts.accessToken;
            }
            if (queryParams.access_token) {
                delete queryParams.access_token;
            }
-        } else {
-            if (!queryParams.access_token) {
-                queryParams.access_token = this.opts.accessToken;
-            }
+        } else if (!queryParams.access_token) {
+            queryParams.access_token = this.opts.accessToken;
        }

-        const requestPromise = this.request(
-            callback, method, path, queryParams, data, opts,
-        );
+        const requestPromise = this.request<T, O>(callback, method, path, queryParams, data, requestOpts);

-        const self = this;
-        requestPromise.catch(function(err) {
-            if (err.errcode == 'M_UNKNOWN_TOKEN') {
-                self.event_emitter.emit("Session.logged_out", err);
+        requestPromise.catch((err: MatrixError) => {
+            if (err.errcode == 'M_UNKNOWN_TOKEN' && !requestOpts?.inhibitLogoutEmit) {
+                this.eventEmitter.emit(HttpApiEvent.SessionLoggedOut, err);
            } else if (err.errcode == 'M_CONSENT_NOT_GIVEN') {
-                self.event_emitter.emit(
-                    "no_consent",
-                    err.message,
-                    err.data.consent_uri,
-                );
+                this.eventEmitter.emit(HttpApiEvent.NoConsent, err.message, err.data.consent_uri);
            }
        });

        // return the original promise, otherwise tests break due to it having to
        // go around the event loop one more time to process the result of the request
        return requestPromise;
-    },
+    }

    /**
     * Perform a request to the homeserver without any credentials.
@@ -529,7 +645,7 @@ MatrixHttpApi.prototype = {
     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
     * timing out the request. If not specified, there is no timeout.
     *
-     * @param {sting=} opts.prefix The full prefix to use e.g.
+     * @param {string=} opts.prefix The full prefix to use e.g.
     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
     *
     * @param {Object=} opts.headers map of additional request headers
@@ -541,15 +657,19 @@ MatrixHttpApi.prototype = {
     * @return {module:http-api.MatrixError} Rejects with an error if a problem
     * occurred. This includes network problems and Matrix-specific error JSON.
     */
-    request: function(callback, method, path, queryParams, data, opts) {
-        opts = opts || {};
-        const prefix = opts.prefix !== undefined ? opts.prefix : this.opts.prefix;
+    public request<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
+        callback: Callback<T>,
+        method: Method,
+        path: string,
+        queryParams?: CoreOptions["qs"],
+        data?: CoreOptions["body"],
+        opts?: O,
+    ): IAbortablePromise<ResponseType<T, O>> {
+        const prefix = opts?.prefix ?? this.opts.prefix;
        const fullUri = this.opts.baseUrl + prefix + path;

-        return this.requestOtherUrl(
-            callback, method, fullUri, queryParams, data, opts,
-        );
-    },
+        return this.requestOtherUrl<T, O>(callback, method, fullUri, queryParams, data, opts);
+    }

    /**
     * Perform a request to an arbitrary URL.
@@ -568,7 +688,7 @@ MatrixHttpApi.prototype = {
     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
     * timing out the request. If not specified, there is no timeout.
     *
-     * @param {sting=} opts.prefix The full prefix to use e.g.
+     * @param {string=} opts.prefix The full prefix to use e.g.
     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
     *
     * @param {Object=} opts.headers map of additional request headers
@@ -580,21 +700,24 @@ MatrixHttpApi.prototype = {
     * @return {module:http-api.MatrixError} Rejects with an error if a problem
     * occurred. This includes network problems and Matrix-specific error JSON.
     */
-    requestOtherUrl: function(callback, method, uri, queryParams, data,
-                              opts) {
-        if (opts === undefined || opts === null) {
-            opts = {};
-        } else if (isFinite(opts)) {
+    public requestOtherUrl<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
+        callback: Callback<T>,
+        method: Method,
+        uri: string,
+        queryParams?: CoreOptions["qs"],
+        data?: CoreOptions["body"],
+        opts?: O | number, // number is legacy
+    ): IAbortablePromise<ResponseType<T, O>> {
+        let requestOpts = (opts || {}) as O;
+        if (isFinite(opts as number)) {
            // opts used to be localTimeoutMs
-            opts = {
-                localTimeoutMs: opts,
-            };
+            requestOpts = {
+                localTimeoutMs: opts as number,
+            } as O;
        }

-        return this._request(
-            callback, method, uri, queryParams, data, opts,
-        );
-    },
+        return this.doRequest<T, O>(callback, method, uri, queryParams, data, requestOpts);
+    }

    /**
     * Form and return a homeserver request URL based on the given path
@@ -607,13 +730,13 @@ MatrixHttpApi.prototype = {
     * "/_matrix/client/v2_alpha".
     * @return {string} URL
     */
-    getUrl: function(path, queryParams, prefix) {
+    public getUrl(path: string, queryParams: CoreOptions["qs"], prefix: string): string {
        let queryString = "";
        if (queryParams) {
            queryString = "?" + utils.encodeParams(queryParams);
        }
        return this.opts.baseUrl + prefix + path + queryString;
-    },
+    }

    /**
     * @private
@@ -640,25 +763,32 @@ MatrixHttpApi.prototype = {
     * @return {Promise} a promise which resolves to either the
     * response object (if this.opts.onlyData is truthy), or the parsed
     * body. Rejects
+     *
+     * Generic T is the callback/promise resolve type
+     * Generic O should be inferred
     */
-    _request: function(callback, method, uri, queryParams, data, opts) {
+    private doRequest<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
+        callback: Callback<T>,
+        method: Method,
+        uri: string,
+        queryParams?: Record<string, string>,
+        data?: CoreOptions["body"],
+        opts?: O,
+    ): IAbortablePromise<ResponseType<T, O>> {
        if (callback !== undefined && !utils.isFunction(callback)) {
-            throw Error(
-                "Expected callback to be a function but got " + typeof callback,
-            );
+            throw Error("Expected callback to be a function but got " + typeof callback);
        }
-        opts = opts || {};

-        const self = this;
        if (this.opts.extraParams) {
            queryParams = {
-              ...queryParams,
-              ...this.opts.extraParams,
+                ...(queryParams || {}),
+                ...this.opts.extraParams,
            };
        }

-        const headers = utils.extend({}, opts.headers || {});
-        const json = opts.json === undefined ? true : opts.json;
+        const headers = Object.assign({}, opts.headers || {});
+        if (!opts) opts = {} as O;
+        const json = opts.json ?? true;
        let bodyParser = opts.bodyParser;

        // we handle the json encoding/decoding here, because request and
@@ -677,17 +807,17 @@ MatrixHttpApi.prototype = {
            }

            if (bodyParser === undefined) {
-                bodyParser = function(rawBody) {
+                bodyParser = function(rawBody: string) {
                    return JSON.parse(rawBody);
                };
            }
        }

-        const defer = utils.defer();
+        const defer = utils.defer<T>();

-        let timeoutId;
+        let timeoutId: number;
        let timedOut = false;
-        let req;
+        let req: IRequest;
        const localTimeoutMs = opts.localTimeoutMs || this.opts.localTimeoutMs;

        const resetTimeout = () => {
@@ -697,9 +827,7 @@ MatrixHttpApi.prototype = {
                }
                timeoutId = callbacks.setTimeout(function() {
                    timedOut = true;
-                    if (req && req.abort) {
-                        req.abort();
-                    }
+                    req?.abort?.();
                    defer.reject(new MatrixError({
                        error: "Locally timed out waiting for a response",
                        errcode: "ORG.MATRIX.JSSDK_TIMEOUT",
@@ -710,7 +838,7 @@ MatrixHttpApi.prototype = {
        };
        resetTimeout();

-        const reqPromise = defer.promise;
+        const reqPromise = defer.promise as IAbortablePromise<ResponseType<T, O>>;

        try {
            req = this.opts.request(
@@ -727,7 +855,7 @@ MatrixHttpApi.prototype = {
                    headers: headers || {},
                    _matrix_opts: this.opts,
                },
-                function(err, response, body) {
+                (err, response, body) => {
                    if (localTimeoutMs) {
                        callbacks.clearTimeout(timeoutId);
                        if (timedOut) {
@@ -735,16 +863,13 @@ MatrixHttpApi.prototype = {
                        }
                    }

-                    const handlerFn = requestCallback(
-                        defer, callback, self.opts.onlyData,
-                        bodyParser,
-                    );
+                    const handlerFn = requestCallback(defer, callback, this.opts.onlyData, bodyParser);
                    handlerFn(err, response, body);
                },
            );
            if (req) {
                // This will only work in a browser, where opts.request is the
-                // `browser-request` import. Currently `request` does not support progress
+                // `browser-request` import. Currently, `request` does not support progress
                // updates - see https://github.com/request/request/pull/2346.
                // `browser-request` returns an XHRHttpRequest which exposes `onprogress`
                if ('onprogress' in req) {
@@ -757,7 +882,9 @@ MatrixHttpApi.prototype = {

                // FIXME: This is EVIL, but I can't think of a better way to expose
                // abort() operations on underlying HTTP requests :(
-                if (req.abort) reqPromise.abort = req.abort.bind(req);
+                if (req.abort) {
+                    reqPromise.abort = req.abort.bind(req);
+                }
            }
        } catch (ex) {
            defer.reject(ex);
@@ -766,8 +893,21 @@ MatrixHttpApi.prototype = {
            }
        }
        return reqPromise;
-    },
-};
+    }
+}
+
+type RequestCallback = (err?: Error, response?: XMLHttpRequest | IncomingMessage, body?: string) => void;
+
+// if using onlyData=false then wrap your expected data type in this generic
+export interface IResponse<T> {
+    code: number;
+    data: T;
+    headers?: IncomingHttpHeaders;
+}
+
+function getStatusCode(response: XMLHttpRequest | IncomingMessage): number {
+    return (response as XMLHttpRequest).status || (response as IncomingMessage).statusCode;
+}

 /*
 * Returns a callback that can be invoked by an HTTP request on completion,
@@ -783,17 +923,17 @@ MatrixHttpApi.prototype = {
 * response, otherwise the result object (with `code` and `data` fields)
 *
 */
-const requestCallback = function(
-    defer, userDefinedCallback, onlyData,
-    bodyParser,
-) {
-    userDefinedCallback = userDefinedCallback || function() {};
-
-    return function(err, response, body) {
+function requestCallback<T>(
+    defer: IDeferred<T>,
+    userDefinedCallback?: Callback<T>,
+    onlyData = false,
+    bodyParser?: (body: string) => T,
+): RequestCallback {
+    return function(err: Error, response: XMLHttpRequest | IncomingMessage, body: string): void {
        if (err) {
            // the unit tests use matrix-mock-request, which throw the string "aborted" when aborting a request.
            // See https://github.com/matrix-org/matrix-mock-request/blob/3276d0263a561b5b8326b47bae720578a2c7473a/src/index.js#L48
-            const aborted = err.name === "AbortError" || err === "aborted";
+            const aborted = err.name === "AbortError" || (err as any as string) === "aborted";
            if (!aborted && !(err instanceof MatrixError)) {
                // browser-request just throws normal Error objects,
                // not `TypeError`s like fetch does. So just assume any
@@ -801,13 +941,15 @@ const requestCallback = function(
                err = new ConnectionError("request failed", err);
            }
        }
+
+        let data: T | string = body;
+
        if (!err) {
            try {
-                const httpStatus = response.status || response.statusCode; // XMLHttpRequest vs http.IncomingMessage
-                if (httpStatus >= 400) {
+                if (getStatusCode(response) >= 400) {
                    err = parseErrorResponse(response, body);
                } else if (bodyParser) {
-                    body = bodyParser(body);
+                    data = bodyParser(body);
                }
            } catch (e) {
                err = new Error(`Error parsing server response: ${e}`);
@@ -816,21 +958,26 @@ const requestCallback = function(

        if (err) {
            defer.reject(err);
-            userDefinedCallback(err);
+            userDefinedCallback?.(err);
+        } else if (onlyData) {
+            defer.resolve(data as T);
+            userDefinedCallback?.(null, data as T);
        } else {
-            const res = {
-                code: response.status || response.statusCode, // XMLHttpRequest vs http.IncomingMessage
+            const res: IResponse<T> = {
+                code: getStatusCode(response),

                // XXX: why do we bother with this? it doesn't work for
                // XMLHttpRequest, so clearly we don't use it.
-                headers: response.headers,
-                data: body,
+                headers: (response as IncomingMessage).headers,
+                data: data as T,
            };
-            defer.resolve(onlyData ? body : res);
-            userDefinedCallback(null, onlyData ? body : res);
+            // XXX: the variations in caller-expected types here are horrible,
+            // typescript doesn't do conditional types based on runtime values
+            defer.resolve(res as any as T);
+            userDefinedCallback?.(null, res as any as T);
        }
    };
-};
+}

 /**
 * Attempt to turn an HTTP error response into a Javascript Error.
@@ -842,8 +989,8 @@ const requestCallback = function(
 * @param {String} body raw body of the response
 * @returns {Error}
 */
-function parseErrorResponse(response, body) {
-    const httpStatus = response.status || response.statusCode; // XMLHttpRequest vs http.IncomingMessage
+function parseErrorResponse(response: XMLHttpRequest | IncomingMessage, body?: string) {
+    const httpStatus = getStatusCode(response);
    const contentType = getResponseContentType(response);

    let err;
@@ -872,14 +1019,14 @@ function parseErrorResponse(response, body) {
 * @param {XMLHttpRequest|http.IncomingMessage} response response object
 * @returns {{type: String, parameters: Object}?} parsed content-type header, or null if not found
 */
-function getResponseContentType(response) {
+function getResponseContentType(response: XMLHttpRequest | IncomingMessage): ParsedMediaType {
    let contentType;
-    if (response.getResponseHeader) {
+    if ((response as XMLHttpRequest).getResponseHeader) {
        // XMLHttpRequest provides getResponseHeader
-        contentType = response.getResponseHeader("Content-Type");
-    } else if (response.headers) {
+        contentType = (response as XMLHttpRequest).getResponseHeader("Content-Type");
+    } else if ((response as IncomingMessage).headers) {
        // request provides http.IncomingMessage which has a message.headers map
-        contentType = response.headers['content-type'] || null;
+        contentType = (response as IncomingMessage).headers['content-type'] || null;
    }

    if (!contentType) {
@@ -893,6 +1040,12 @@ function getResponseContentType(response) {
    }
 }

+interface IErrorJson extends Partial<IUsageLimit> {
+    [key: string]: any; // extensible
+    errcode?: string;
+    error?: string;
+}
+
 /**
 * Construct a Matrix error. This is a JavaScript Error with additional
 * information specific to the standard Matrix error response.
@@ -905,8 +1058,11 @@ function getResponseContentType(response) {
 * @prop {integer} httpStatus The numeric HTTP status code given
 */
 export class MatrixError extends Error {
-    constructor(errorJson) {
-        errorJson = errorJson || {};
+    public readonly errcode: string;
+    public readonly data: IErrorJson;
+    public httpStatus?: number; // set by http-api
+
+    constructor(errorJson: IErrorJson = {}) {
        super(`MatrixError: ${errorJson.errcode}`);
        this.errcode = errorJson.errcode;
        this.name = errorJson.errcode || "Unknown error code";
@@ -923,18 +1079,13 @@ export class MatrixError extends Error {
 * @constructor
 */
 export class ConnectionError extends Error {
-    constructor(message, cause = undefined) {
+    constructor(message: string, private readonly cause: Error = undefined) {
        super(message + (cause ? `: ${cause.message}` : ""));
-        this._cause = cause;
    }

    get name() {
        return "ConnectionError";
    }
-
-    get cause() {
-        return this._cause;
-    }
 }

 export class AbortError extends Error {
@@ -954,7 +1105,7 @@ export class AbortError extends Error {
 * @return {any} the result of the network operation
 * @throws {ConnectionError} If after maxAttempts the callback still throws ConnectionError
 */
-export async function retryNetworkOperation(maxAttempts, callback) {
+export async function retryNetworkOperation<T>(maxAttempts: number, callback: () => T): Promise<T> {
    let attempts = 0;
    let lastConnectionError = null;
    while (attempts < maxAttempts) {
--- a/Show More
+++ b/Show More