Improve test coverage for cli/src/ui/components (#13598)

packages/cli/src/ui/components/messages/UserMessage.test.tsx

@@ -0,0 +1,40 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { render } from '../../../test-utils/render.js';
+import { UserMessage } from './UserMessage.js';
+import { describe, it, expect, vi } from 'vitest';
+
+// Mock the commandUtils to control isSlashCommand behavior
+vi.mock('../../utils/commandUtils.js', () => ({
+  isSlashCommand: vi.fn((text: string) => text.startsWith('/')),
+}));
+
+describe('UserMessage', () => {
+  it('renders normal user message with correct prefix', () => {
+    const { lastFrame } = render(
+      <UserMessage text="Hello Gemini" width={80} />,
+    );
+    const output = lastFrame();
+
+    expect(output).toMatchSnapshot();
+  });
+
+  it('renders slash command message', () => {
+    const { lastFrame } = render(<UserMessage text="/help" width={80} />);
+    const output = lastFrame();
+
+    expect(output).toMatchSnapshot();
+  });
+
+  it('renders multiline user message', () => {
+    const message = 'Line 1\nLine 2';
+    const { lastFrame } = render(<UserMessage text={message} width={80} />);
+    const output = lastFrame();
+
+    expect(output).toMatchSnapshot();
+  });
+});