[PM-17710] Fix NotificationCenterServiceTests race condition failure

BitwardenShared/Core/Platform/Services/NotificationCenterServiceTests.swift

@@ -7,46 +7,70 @@ final class NotificationCenterServiceTests: BitwardenTestCase {
 
     var notificationCenter: NotificationCenter!
     var subject: DefaultNotificationCenterService!
+    var didEnterBackgroundTask: Task<Void, Never>!
+    var didEnterBackgroundPublished: Bool = false
+    var willEnterForegroundTask: Task<Void, Never>!
+    var willEnterBackgroundPublished: Bool = false
 
     // MARK: Setup & Teardown
 
     override func setUp() {
         notificationCenter = NotificationCenter()
         subject = DefaultNotificationCenterService(notificationCenter: notificationCenter)
+
+        didEnterBackgroundTask = Task {
+            for await _ in subject.didEnterBackgroundPublisher() {
+                didEnterBackgroundPublished = true
+            }
+        }
+
+        willEnterForegroundTask = Task {
+            for await _ in subject.willEnterForegroundPublisher() {
+                willEnterBackgroundPublished = true
+            }
+        }
     }
 
     override func tearDown() {
+        didEnterBackgroundPublished = false
+        didEnterBackgroundTask?.cancel()
+        didEnterBackgroundTask = nil
+
+        willEnterBackgroundPublished = false
+        willEnterForegroundTask?.cancel()
+        willEnterForegroundTask = nil
+
         notificationCenter = nil
         subject = nil
     }
 
     // MARK: Tests
 
     /// `didEnterBackgroundPublisher` publishes a notification when the app enters the background.
-    func testDidEnterBackgroundPublisher() async throws {
-        var iterator = subject.didEnterBackgroundPublisher().makeAsyncIterator()
-        Task {
-            notificationCenter.post(
-                name: UIApplication.didEnterBackgroundNotification,
-                object: nil
-            )
+    func test_didEnterBackgroundPublisher() async throws {
+        try await waitForAsync { [weak self] in
+            let task = Task {
+                self?.notificationCenter.post(
+                    name: UIApplication.didEnterBackgroundNotification,
+                    object: nil
+                )
+            }
+            defer { task.cancel() }
+            return self?.didEnterBackgroundPublished == true
         }
-        let result: Void? = await iterator.next()
-
-        XCTAssertNotNil(result)
     }
 
     /// `willEnterForegroundPublisher` publishes a notification when the app will enter the foreground.
-    func testWillEnterForegroundPublisher() async throws {
-        var iterator = subject.willEnterForegroundPublisher().makeAsyncIterator()
-        Task {
-            notificationCenter.post(
-                name: UIApplication.willEnterForegroundNotification,
-                object: nil
-            )
+    func test_willEnterForegroundPublisher() async throws {
+        try await waitForAsync { [weak self] in
+            let task = Task {
+                self?.notificationCenter.post(
+                    name: UIApplication.willEnterForegroundNotification,
+                    object: nil
+                )
+            }
+            defer { task.cancel() }
+            return self?.willEnterBackgroundPublished == true
         }
-        let result: Void? = await iterator.next()
-
-        XCTAssertNotNil(result)
     }
 }