From 3378d18ca82acfd945b74cb9bf8e6f31c0163ef0 Mon Sep 17 00:00:00 2001
From: Julian Sparber <julian@sparber.net>
Date: Tue, 22 Feb 2022 16:49:42 +0100
Subject: [PATCH] store: Add comment why we can ignore unexpected
 TimelineSlices

---
 crates/matrix-sdk-base/src/store/indexeddb_store.rs | 3 +++
 crates/matrix-sdk-base/src/store/memory_store.rs    | 3 +++
 crates/matrix-sdk-base/src/store/sled_store.rs      | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/crates/matrix-sdk-base/src/store/indexeddb_store.rs b/crates/matrix-sdk-base/src/store/indexeddb_store.rs
index 161cd37d3..6dc9ec5e3 100644
--- a/crates/matrix-sdk-base/src/store/indexeddb_store.rs
+++ b/crates/matrix-sdk-base/src/store/indexeddb_store.rs
@@ -525,6 +525,9 @@ impl IndexeddbStore {
                         .transpose()?;
                     if let Some(mut metadata) = metadata {
                         if !timeline.sync && Some(&timeline.start) != metadata.end.as_ref() {
+                            // This should only happen when a developer adds a wrong timeline
+                            // batch to the `StateChanges` or the server returns a wrong response
+                            // to our request.
                             warn!("Drop unexpected timeline batch for {}", room_id);
                             return Ok(());
                         }
diff --git a/crates/matrix-sdk-base/src/store/memory_store.rs b/crates/matrix-sdk-base/src/store/memory_store.rs
index d84b447f2..ef173df72 100644
--- a/crates/matrix-sdk-base/src/store/memory_store.rs
+++ b/crates/matrix-sdk-base/src/store/memory_store.rs
@@ -290,6 +290,9 @@ impl MemoryStore {
                 None
             } else if let Some(mut data) = self.room_timeline.get_mut(room) {
                 if !timeline.sync && Some(&timeline.start) != data.end.as_ref() {
+                    // This should only happen when a developer adds a wrong timeline
+                    // batch to the `StateChanges` or the server returns a wrong response
+                    // to our request.
                     warn!("Drop unexpected timeline batch for {}", room);
                     return Ok(());
                 }
diff --git a/crates/matrix-sdk-base/src/store/sled_store.rs b/crates/matrix-sdk-base/src/store/sled_store.rs
index 1070a1e45..a4aca43bb 100644
--- a/crates/matrix-sdk-base/src/store/sled_store.rs
+++ b/crates/matrix-sdk-base/src/store/sled_store.rs
@@ -1093,6 +1093,9 @@ impl SledStore {
                     .transpose()?;
                 if let Some(mut metadata) = metadata {
                     if !timeline.sync && Some(&timeline.start) != metadata.end.as_ref() {
+                        // This should only happen when a developer adds a wrong timeline
+                        // batch to the `StateChanges` or the server returns a wrong response
+                        // to our request.
                         warn!("Drop unexpected timeline batch for {}", room_id);
                         return Ok(());
                     }