Emit UnreadNotification event on notifications reset (#2804)

spec/unit/room.spec.ts

@@ -2723,6 +2723,19 @@ describe("Room", function() {
             expect(room.getThreadUnreadNotificationCount("123", NotificationCountType.Total)).toBe(666);
             expect(room.getThreadUnreadNotificationCount("456", NotificationCountType.Highlight)).toBe(0);
         });
+
+        it("emits event on notifications reset", () => {
+            const cb = jest.fn();
+
+            room.on(RoomEvent.UnreadNotifications, cb);
+
+            room.setThreadUnreadNotificationCount("123", NotificationCountType.Total, 666);
+            room.setThreadUnreadNotificationCount("456", NotificationCountType.Highlight, 123);
+
+            room.resetThreadUnreadNotificationCount();
+
+            expect(cb).toHaveBeenLastCalledWith();
+        });
     });
 
     describe("hasThreadUnreadNotification", () => {

src/models/room.ts

@@ -173,7 +173,7 @@ export type RoomEventHandlerMap = {
         room: Room,
     ) => void;
     [RoomEvent.UnreadNotifications]: (
-        unreadNotifications: NotificationCount,
+        unreadNotifications?: NotificationCount,
         threadId?: string,
     ) => void;
     [RoomEvent.TimelineRefresh]: (room: Room, eventTimelineSet: EventTimelineSet) => void;
@@ -1277,6 +1277,7 @@ export class Room extends ReadReceipt<RoomEmittedEvents, RoomEventHandlerMap> {
         } else {
             this.threadNotifications.clear();
         }
+        this.emit(RoomEvent.UnreadNotifications);
     }
 
     /**