Re-add truthy check on room name/avatar/alias events (#5081)

* Re-add truthy check on room name/avatar/alias events

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

* Add regression test

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

---------

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

spec/unit/models/room.spec.ts

@@ -229,4 +229,27 @@ describe("Room", () => {
             expect(room.getAltAliases()).toEqual(["#foo:bar"]);
         });
     });
+
+    describe("calculateRoomName()", () => {
+        it("should ignore empty m.room.name 'name' field", async () => {
+            const mockClient = createMockClient();
+            const room = new Room("!room:example.org", mockClient, CREATOR_USER_ID);
+            const event = new MatrixEvent({
+                type: EventType.RoomName,
+                content: {
+                    name: "",
+                },
+                state_key: "",
+                event_id: "$123",
+                room_id: room.roomId,
+                sender: CREATOR_USER_ID,
+            });
+
+            // Set up the room
+            room.currentState.setStateEvents([event]);
+            room.recalculate();
+
+            expect(room.name).not.toEqual("");
+        });
+    });
 });

src/models/room.ts

@@ -1810,7 +1810,7 @@ export class Room extends ReadReceipt<RoomEmittedEvents, RoomEventHandlerMap> {
      */
     public getMxcAvatarUrl(): string | null {
         const url = this.currentState.getStateEvents(EventType.RoomAvatar, "")?.getContent().url;
-        return typeof url === "string" ? url : null;
+        return url && typeof url === "string" ? url : null;
     }
 
     /**
@@ -1821,7 +1821,7 @@ export class Room extends ReadReceipt<RoomEmittedEvents, RoomEventHandlerMap> {
      */
     public getCanonicalAlias(): string | null {
         const canonicalAlias = this.currentState.getStateEvents(EventType.RoomCanonicalAlias, "")?.getContent().alias;
-        return typeof canonicalAlias === "string" ? canonicalAlias : null;
+        return canonicalAlias && typeof canonicalAlias === "string" ? canonicalAlias : null;
     }
 
     /**
@@ -3638,7 +3638,7 @@ export class Room extends ReadReceipt<RoomEmittedEvents, RoomEventHandlerMap> {
     private calculateRoomName(userId: string, ignoreRoomNameEvent = false): string {
         if (!ignoreRoomNameEvent) {
             const name = this.currentState.getStateEvents(EventType.RoomName, "")?.getContent().name;
-            if (typeof name === "string") {
+            if (name && typeof name === "string") {
                 return this.roomNameGenerator({
                     type: RoomNameType.Actual,
                     name,