Add test for RoomNotificationState (#7820)

Regression test for https://github.com/vector-im/element-web/issues/20859

test/stores/notifications/RoomNotificationState-test.ts

@@ -0,0 +1,43 @@
+/*
+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 { Room } from "matrix-js-sdk";
+
+import "../../skinned-sdk";
+import { stubClient } from "../../test-utils";
+import { MatrixClientPeg } from "../../../src/MatrixClientPeg";
+import { RoomNotificationState } from "../../../src/stores/notifications/RoomNotificationState";
+import * as testUtils from "../../test-utils";
+import { NotificationStateEvents } from "../../../src/stores/notifications/NotificationState";
+
+describe("RoomNotificationState", () => {
+    stubClient();
+    const client = MatrixClientPeg.get();
+
+    it("Updates on event decryption", () => {
+        const testRoom = testUtils.mkStubRoom(client, "$aroomid", "Test room");
+
+        const roomNotifState = new RoomNotificationState(testRoom as any as Room);
+        const listener = jest.fn();
+        roomNotifState.addListener(NotificationStateEvents.Update, listener);
+        const testEvent = {
+            getRoomId: () => testRoom.roomId,
+        };
+        testRoom.getUnreadNotificationCount = jest.fn().mockReturnValue(1);
+        client.emit("Event.decrypted", testEvent);
+        expect(listener).toHaveBeenCalled();
+    });
+});