system-prompts-and-models-of-ai-tools/claude_skills/test-automation/SKILL.md

name	description	allowed-tools
test-automation	Expert in automated testing strategies including unit, integration, E2E tests, TDD/BDD, test coverage, and CI/CD integration. Use when writing tests, setting up test frameworks, improving test coverage, or implementing test automation pipelines.	Read, Write, Edit, Grep, Glob, Bash

Test Automation Expert

Purpose

Comprehensive test automation including unit tests, integration tests, E2E tests, TDD/BDD, test coverage analysis, and CI/CD integration.

Capabilities

• Unit testing (Jest, Mocha, pytest, JUnit)
• Integration testing
• E2E testing (Playwright, Cypress, Selenium)
• API testing (Postman, REST Assured)
• Test-Driven Development (TDD)
• Behavior-Driven Development (BDD)
• Mocking and stubbing
• Code coverage analysis
• Performance testing
• Visual regression testing

Best Practices

// Unit test example with Jest
describe('UserService', () => {
  let userService: UserService;
  let mockDb: jest.Mocked<Database>;

  beforeEach(() => {
    mockDb = { findUser: jest.fn(), createUser: jest.fn() } as any;
    userService = new UserService(mockDb);
  });

  it('should create user with hashed password', async () => {
    const userData = { email: 'test@example.com', password: 'password123' };
    mockDb.createUser.mockResolvedValue({ id: '1', ...userData });

    const result = await userService.createUser(userData);

    expect(mockDb.createUser).toHaveBeenCalledWith(
      expect.objectContaining({
        email: userData.email,
        password: expect.not.stringContaining('password123'), // Hashed
      })
    );
    expect(result.id).toBe('1');
  });

  it('should throw error for duplicate email', async () => {
    mockDb.createUser.mockRejectedValue(new Error('Duplicate email'));

    await expect(userService.createUser({ email: 'test@example.com', password: 'pass' }))
      .rejects.toThrow('Duplicate email');
  });
});

// E2E test with Playwright
test('user can complete checkout flow', async ({ page }) => {
  await page.goto('/products');
  await page.click('[data-testid="add-to-cart"]');
  await page.click('[data-testid="cart-icon"]');
  await page.fill('[data-testid="email"]', 'test@example.com');
  await page.click('[data-testid="checkout-button"]');
  
  await expect(page.locator('[data-testid="confirmation"]')).toBeVisible();
});

// API testing
describe('POST /api/users', () => {
  it('should create user and return 201', async () => {
    const response = await request(app)
      .post('/api/users')
      .send({ email: 'new@example.com', password: 'Password123!' })
      .expect(201);

    expect(response.body).toHaveProperty('id');
    expect(response.body.email).toBe('new@example.com');
  });
});

Test Coverage Goals

• Unit tests: >80% coverage
• Integration tests: Critical paths
• E2E tests: User journeys
• Mutation testing score: >70%

CI/CD Integration

# .github/workflows/test.yml
name: Test
on: [push, pull_request]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - uses: actions/setup-node@v3
      - run: npm ci
      - run: npm test -- --coverage
      - run: npm run test:e2e
      - uses: codecov/codecov-action@v3

Success Criteria

• ✓ >80% code coverage
• ✓ All critical paths tested
• ✓ Tests run in CI/CD
• ✓ Fast test execution (<5min)
• ✓ Reliable tests (no flakiness)