Improve code coverage for cli package (#13724)

packages/cli/src/utils/events.test.ts

@@ -0,0 +1,32 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect, vi } from 'vitest';
+import { appEvents, AppEvent } from './events.js';
+
+describe('events', () => {
+  it('should allow registering and emitting events', () => {
+    const callback = vi.fn();
+    appEvents.on(AppEvent.OauthDisplayMessage, callback);
+
+    appEvents.emit(AppEvent.OauthDisplayMessage, 'test message');
+
+    expect(callback).toHaveBeenCalledWith('test message');
+
+    appEvents.off(AppEvent.OauthDisplayMessage, callback);
+  });
+
+  it('should work with events without data', () => {
+    const callback = vi.fn();
+    appEvents.on(AppEvent.Flicker, callback);
+
+    appEvents.emit(AppEvent.Flicker);
+
+    expect(callback).toHaveBeenCalled();
+
+    appEvents.off(AppEvent.Flicker, callback);
+  });
+});