Playwright E2E Testing Skill
progressive_disclosure: entry_point: summary: "Modern E2E testing framework with cross-browser automation and built-in test runner" when_to_use: - "When testing web applications end-to-end" - "When needing cross-browser testing" - "When testing user flows and interactions" - "When needing screenshot/video recording" quick_start: - "npm init playwright@latest" - "Choose TypeScript and test location" - "npx playwright test" - "npx playwright show-report" token_estimate: entry: 75-90 full: 4200-5200
Overview
Playwright is a modern end-to-end testing framework that provides cross-browser automation with a built-in test runner, auto-wait mechanisms, and excellent developer experience.
Key Features
- Auto-wait: Automatically waits for elements to be ready
- Cross-browser: Chromium, Firefox, WebKit support
- Built-in runner: Parallel execution, retries, reporters
- Network control: Mock and intercept network requests
- Debugging: UI mode, trace viewer, inspector
Installation
bash# Initialize new Playwright project npm init playwright@latest # Or add to existing project npm install -D @playwright/test # Install browsers npx playwright install
Configuration
typescript// playwright.config.ts import { defineConfig, devices } from '@playwright/test'; export default defineConfig({ testDir: './tests', fullyParallel: true, forbidOnly: !!process.env.CI, retries: process.env.CI ? 2 : 0, workers: process.env.CI ? 1 : undefined, reporter: 'html', use: { baseURL: 'http://localhost:3000', trace: 'on-first-retry', screenshot: 'only-on-failure', }, projects: [ { name: 'chromium', use: { ...devices['Desktop Chrome'] }, }, { name: 'firefox', use: { ...devices['Desktop Firefox'] }, }, { name: 'webkit', use: { ...devices['Desktop Safari'] }, }, { name: 'Mobile Chrome', use: { ...devices['Pixel 5'] }, }, ], webServer: { command: 'npm run start', url: 'http://localhost:3000', reuseExistingServer: !process.env.CI, }, });
Fundamentals
Basic Test Structure
typescriptimport { test, expect } from '@playwright/test'; test('basic test', async ({ page }) => { await page.goto('https://example.com'); // Wait for element and check visibility const title = page.locator('h1'); await expect(title).toBeVisible(); await expect(title).toHaveText('Example Domain'); // Get page title await expect(page).toHaveTitle(/Example/); }); test.describe('User authentication', () => { test('should login successfully', async ({ page }) => { await page.goto('/login'); await page.fill('[name="username"]', 'testuser'); await page.fill('[name="password"]', 'password123'); await page.click('button[type="submit"]'); await expect(page).toHaveURL('/dashboard'); await expect(page.locator('.welcome-message')).toContainText('Welcome'); }); test('should show error for invalid credentials', async ({ page }) => { await page.goto('/login'); await page.fill('[name="username"]', 'invalid'); await page.fill('[name="password"]', 'wrong'); await page.click('button[type="submit"]'); await expect(page.locator('.error-message')).toBeVisible(); await expect(page.locator('.error-message')).toHaveText('Invalid credentials'); }); });
Test Hooks
typescriptimport { test, expect } from '@playwright/test'; test.describe('Dashboard tests', () => { test.beforeEach(async ({ page }) => { // Run before each test await page.goto('/dashboard'); await page.waitForLoadState('networkidle'); }); test.afterEach(async ({ page }) => { // Cleanup after each test await page.close(); }); test.beforeAll(async ({ browser }) => { // Run once before all tests in describe block console.log('Starting test suite'); }); test.afterAll(async ({ browser }) => { // Run once after all tests console.log('Test suite complete'); }); test('displays user data', async ({ page }) => { await expect(page.locator('.user-name')).toBeVisible(); }); });
Locator Strategies
Best Practice: Role-based Locators
typescriptimport { test, expect } from '@playwright/test'; test('accessible locators', async ({ page }) => { await page.goto('/form'); // By role (BEST - accessible and stable) await page.getByRole('button', { name: 'Submit' }).click(); await page.getByRole('textbox', { name: 'Email' }).fill('user@example.com'); await page.getByRole('checkbox', { name: 'Subscribe' }).check(); await page.getByRole('link', { name: 'Learn more' }).click(); // By label (good for forms) await page.getByLabel('Password').fill('secret123'); // By placeholder await page.getByPlaceholder('Search...').fill('query'); // By text await page.getByText('Welcome back').click(); await page.getByText(/hello/i).isVisible(); // By test ID (good for dynamic content) await page.getByTestId('user-profile').click(); // By title await page.getByTitle('Close dialog').click(); // By alt text (images) await page.getByAltText('User avatar').click(); });
CSS and XPath Locators
typescripttest('CSS and XPath locators', async ({ page }) => { // CSS selectors await page.locator('button.primary').click(); await page.locator('#user-menu').click(); await page.locator('[data-testid="submit-btn"]').click(); await page.locator('div.card:first-child').click(); // XPath (use sparingly) await page.locator('xpath=//button[contains(text(), "Submit")]').click(); // Chaining locators const form = page.locator('form#login-form'); await form.locator('input[name="email"]').fill('user@example.com'); await form.locator('button[type="submit"]').click(); // Filter locators await page.getByRole('listitem') .filter({ hasText: 'Product 1' }) .getByRole('button', { name: 'Add to cart' }) .click(); });
Page Object Model
Page Class Pattern
typescript// pages/LoginPage.ts import { Page, Locator } from '@playwright/test'; export class LoginPage { readonly page: Page; readonly usernameInput: Locator; readonly passwordInput: Locator; readonly submitButton: Locator; readonly errorMessage: Locator; constructor(page: Page) { this.page = page; this.usernameInput = page.getByLabel('Username'); this.passwordInput = page.getByLabel('Password'); this.submitButton = page.getByRole('button', { name: 'Log in' }); this.errorMessage = page.locator('.error-message'); } async goto() { await this.page.goto('/login'); } async login(username: string, password: string) { await this.usernameInput.fill(username); await this.passwordInput.fill(password); await this.submitButton.click(); } async expectErrorMessage(message: string) { await this.errorMessage.waitFor({ state: 'visible' }); await expect(this.errorMessage).toHaveText(message); } } // pages/DashboardPage.ts export class DashboardPage { readonly page: Page; readonly welcomeMessage: Locator; readonly logoutButton: Locator; constructor(page: Page) { this.page = page; this.welcomeMessage = page.locator('.welcome-message'); this.logoutButton = page.getByRole('button', { name: 'Logout' }); } async waitForLoad() { await this.welcomeMessage.waitFor({ state: 'visible' }); } async logout() { await this.logoutButton.click(); } } // tests/auth.spec.ts import { test, expect } from '@playwright/test'; import { LoginPage } from '../pages/LoginPage'; import { DashboardPage } from '../pages/DashboardPage'; test('successful login flow', async ({ page }) => { const loginPage = new LoginPage(page); const dashboard = new DashboardPage(page); await loginPage.goto(); await loginPage.login('testuser', 'password123'); await dashboard.waitForLoad(); await expect(dashboard.welcomeMessage).toContainText('Welcome'); });
Component Pattern
typescript// components/NavigationComponent.ts import { Page, Locator } from '@playwright/test'; export class NavigationComponent { readonly page: Page; readonly homeLink: Locator; readonly profileLink: Locator; readonly searchInput: Locator; constructor(page: Page) { this.page = page; const nav = page.locator('nav'); this.homeLink = nav.getByRole('link', { name: 'Home' }); this.profileLink = nav.getByRole('link', { name: 'Profile' }); this.searchInput = nav.getByPlaceholder('Search...'); } async navigateToProfile() { await this.profileLink.click(); } async search(query: string) { await this.searchInput.fill(query); await this.searchInput.press('Enter'); } }
User Interactions
Form Interactions
typescripttest('form interactions', async ({ page }) => { await page.goto('/form'); // Text inputs await page.fill('input[name="email"]', 'user@example.com'); await page.type('textarea[name="message"]', 'Hello', { delay: 100 }); // Checkboxes await page.check('input[type="checkbox"][name="subscribe"]'); await page.uncheck('input[type="checkbox"][name="spam"]'); // Radio buttons await page.check('input[type="radio"][value="option1"]'); // Select dropdowns await page.selectOption('select[name="country"]', 'US'); await page.selectOption('select[name="color"]', { label: 'Blue' }); await page.selectOption('select[name="size"]', { value: 'large' }); // Multi-select await page.selectOption('select[multiple]', ['value1', 'value2']); // File uploads await page.setInputFiles('input[type="file"]', 'path/to/file.pdf'); await page.setInputFiles('input[type="file"]', [ 'file1.jpg', 'file2.jpg' ]); // Clear file input await page.setInputFiles('input[type="file"]', []); });
Mouse and Keyboard
typescripttest('mouse and keyboard interactions', async ({ page }) => { // Click variations await page.click('button'); await page.dblclick('button'); // Double click await page.click('button', { button: 'right' }); // Right click await page.click('button', { modifiers: ['Shift'] }); // Shift+click // Hover await page.hover('.tooltip-trigger'); await expect(page.locator('.tooltip')).toBeVisible(); // Drag and drop await page.dragAndDrop('#draggable', '#droppable'); // Keyboard await page.keyboard.press('Enter'); await page.keyboard.press('Control+A'); await page.keyboard.type('Hello World'); await page.keyboard.down('Shift'); await page.keyboard.press('ArrowDown'); await page.keyboard.up('Shift'); // Focus await page.focus('input[name="email"]'); await page.fill('input[name="email"]', 'test@example.com'); });
Waiting Strategies
typescripttest('waiting strategies', async ({ page }) => { // Wait for element await page.waitForSelector('.dynamic-content'); await page.waitForSelector('.modal', { state: 'visible' }); await page.waitForSelector('.loading', { state: 'hidden' }); // Wait for load state await page.waitForLoadState('load'); await page.waitForLoadState('domcontentloaded'); await page.waitForLoadState('networkidle'); // Wait for URL await page.waitForURL('**/dashboard'); await page.waitForURL(/\/product\/\d+/); // Wait for function await page.waitForFunction(() => { return document.querySelectorAll('.item').length > 5; }); // Wait for timeout (avoid if possible) await page.waitForTimeout(1000); // Wait for event await page.waitForEvent('load'); await page.waitForEvent('popup'); });
Assertions
Common Assertions
typescriptimport { test, expect } from '@playwright/test'; test('assertions', async ({ page }) => { await page.goto('/dashboard'); // Visibility await expect(page.locator('.header')).toBeVisible(); await expect(page.locator('.loading')).toBeHidden(); await expect(page.locator('.optional')).not.toBeVisible(); // Text content await expect(page.locator('h1')).toHaveText('Dashboard'); await expect(page.locator('h1')).toContainText('Dash'); await expect(page.locator('.message')).toHaveText(/welcome/i); // Attributes await expect(page.locator('button')).toBeEnabled(); await expect(page.locator('button')).toBeDisabled(); await expect(page.locator('input')).toHaveAttribute('type', 'email'); await expect(page.locator('input')).toHaveValue('test@example.com'); // CSS await expect(page.locator('.button')).toHaveClass('btn-primary'); await expect(page.locator('.button')).toHaveClass(/btn-/); await expect(page.locator('.element')).toHaveCSS('color', 'rgb(255, 0, 0)'); // Count await expect(page.locator('.item')).toHaveCount(5); // URL and title await expect(page).toHaveURL('http://localhost:3000/dashboard'); await expect(page).toHaveURL(/dashboard$/); await expect(page).toHaveTitle('Dashboard - My App'); await expect(page).toHaveTitle(/Dashboard/); // Screenshot comparison await expect(page).toHaveScreenshot('dashboard.png'); await expect(page.locator('.widget')).toHaveScreenshot('widget.png'); });
Custom Assertions
typescripttest('custom matchers', async ({ page }) => { // Soft assertions (continue test on failure) await expect.soft(page.locator('.title')).toHaveText('Welcome'); await expect.soft(page.locator('.subtitle')).toBeVisible(); // Multiple elements const items = page.locator('.item'); await expect(items).toHaveCount(3); await expect(items.nth(0)).toContainText('First'); await expect(items.nth(1)).toContainText('Second'); // Poll assertions await expect(async () => { const response = await page.request.get('/api/status'); expect(response.ok()).toBeTruthy(); }).toPass({ timeout: 10000, intervals: [1000, 2000, 5000], }); });
Authentication Patterns
Storage State Pattern
typescript// auth.setup.ts - Run once to save auth state import { test as setup } from '@playwright/test'; const authFile = 'playwright/.auth/user.json'; setup('authenticate', async ({ page }) => { await page.goto('/login'); await page.fill('[name="username"]', 'testuser'); await page.fill('[name="password"]', 'password123'); await page.click('button[type="submit"]'); await page.waitForURL('/dashboard'); // Save authentication state await page.context().storageState({ path: authFile }); }); // playwright.config.ts export default defineConfig({ projects: [ { name: 'setup', testMatch: /.*\.setup\.ts/, }, { name: 'chromium', use: { ...devices['Desktop Chrome'], storageState: authFile, }, dependencies: ['setup'], }, ], }); // tests/dashboard.spec.ts - Already authenticated test('view dashboard', async ({ page }) => { await page.goto('/dashboard'); // Already logged in! await expect(page.locator('.user-menu')).toBeVisible(); });
Multiple User Roles
typescript// fixtures/auth.ts import { test as base } from '@playwright/test'; type Fixtures = { adminPage: Page; userPage: Page; }; export const test = base.extend<Fixtures>({ adminPage: async ({ browser }, use) => { const context = await browser.newContext({ storageState: 'playwright/.auth/admin.json', }); const page = await context.newPage(); await use(page); await context.close(); }, userPage: async ({ browser }, use) => { const context = await browser.newContext({ storageState: 'playwright/.auth/user.json', }); const page = await context.newPage(); await use(page); await context.close(); }, }); // tests/permissions.spec.ts import { test } from '../fixtures/auth'; test('admin can access admin panel', async ({ adminPage }) => { await adminPage.goto('/admin'); await expect(adminPage.locator('.admin-panel')).toBeVisible(); }); test('regular user cannot access admin panel', async ({ userPage }) => { await userPage.goto('/admin'); await expect(userPage.locator('.access-denied')).toBeVisible(); });
Network Control
Request Mocking
typescripttest('mock API responses', async ({ page }) => { // Mock API response await page.route('**/api/users', route => { route.fulfill({ status: 200, contentType: 'application/json', body: JSON.stringify({ users: [ { id: 1, name: 'John Doe' }, { id: 2, name: 'Jane Smith' }, ], }), }); }); await page.goto('/users'); await expect(page.locator('.user-list')).toContainText('John Doe'); }); test('mock with conditions', async ({ page }) => { await page.route('**/api/**', route => { const url = route.request().url(); if (url.includes('/users/1')) { route.fulfill({ status: 200, body: JSON.stringify({ id: 1, name: 'Test User' }), }); } else if (url.includes('/users')) { route.fulfill({ status: 200, body: JSON.stringify({ users: [] }), }); } else { route.continue(); } }); }); test('simulate network errors', async ({ page }) => { await page.route('**/api/data', route => { route.abort('failed'); }); await page.goto('/data'); await expect(page.locator('.error-message')).toBeVisible(); });
Request Interception
typescripttest('intercept and modify requests', async ({ page }) => { // Modify request headers await page.route('**/api/**', route => { const headers = route.request().headers(); route.continue({ headers: { ...headers, 'X-Custom-Header': 'test-value', }, }); }); // Modify POST data await page.route('**/api/submit', route => { const postData = route.request().postDataJSON(); route.continue({ postData: JSON.stringify({ ...postData, timestamp: Date.now(), }), }); }); }); test('wait for API response', async ({ page }) => { // Wait for specific request const responsePromise = page.waitForResponse('**/api/users'); await page.click('button#load-users'); const response = await responsePromise; expect(response.status()).toBe(200); const data = await response.json(); expect(data.users).toHaveLength(10); });
Test Organization
Custom Fixtures
typescript// fixtures/todos.ts import { test as base } from '@playwright/test'; type TodoFixtures = { todoPage: TodoPage; createTodo: (title: string) => Promise<void>; }; export const test = base.extend<TodoFixtures>({ todoPage: async ({ page }, use) => { const todoPage = new TodoPage(page); await todoPage.goto(); await use(todoPage); }, createTodo: async ({ page }, use) => { const create = async (title: string) => { await page.fill('.new-todo', title); await page.press('.new-todo', 'Enter'); }; await use(create); }, }); // tests/todos.spec.ts import { test } from '../fixtures/todos'; test('can create new todo', async ({ todoPage, createTodo }) => { await createTodo('Buy groceries'); await expect(todoPage.todoItems).toHaveCount(1); await expect(todoPage.todoItems).toHaveText('Buy groceries'); });
Test Tags and Filtering
typescripttest('smoke test', { tag: '@smoke' }, async ({ page }) => { await page.goto('/'); await expect(page).toHaveTitle('Home'); }); test('regression test', { tag: ['@regression', '@critical'] }, async ({ page }) => { // Complex test }); // Run: npx playwright test --grep @smoke // Run: npx playwright test --grep-invert @slow
Visual Testing
Screenshot Comparison
typescripttest('visual regression', async ({ page }) => { await page.goto('/dashboard'); // Full page screenshot await expect(page).toHaveScreenshot('dashboard.png', { maxDiffPixels: 100, }); // Element screenshot await expect(page.locator('.widget')).toHaveScreenshot('widget.png'); // Full page with scroll await expect(page).toHaveScreenshot('full-page.png', { fullPage: true, }); // Mask dynamic elements await expect(page).toHaveScreenshot('masked.png', { mask: [page.locator('.timestamp'), page.locator('.avatar')], }); // Custom threshold await expect(page).toHaveScreenshot('comparison.png', { maxDiffPixelRatio: 0.05, // 5% difference allowed }); });
Video and Trace
typescript// playwright.config.ts export default defineConfig({ use: { video: 'retain-on-failure', trace: 'on-first-retry', screenshot: 'only-on-failure', }, }); // Programmatic video test('record video', async ({ page }) => { await page.goto('/'); // Test actions... // Video saved automatically to test-results/ }); // View trace: npx playwright show-trace trace.zip
Parallel Execution
Test Sharding
typescript// playwright.config.ts export default defineConfig({ fullyParallel: true, workers: process.env.CI ? 4 : undefined, }); // Run shards in CI // npx playwright test --shard=1/4 // npx playwright test --shard=2/4 // npx playwright test --shard=3/4 // npx playwright test --shard=4/4
Serial Tests
typescripttest.describe.configure({ mode: 'serial' }); test.describe('order matters', () => { let orderId: string; test('create order', async ({ page }) => { // Create order orderId = await createOrder(page); }); test('verify order', async ({ page }) => { // Use orderId from previous test await verifyOrder(page, orderId); }); });
CI/CD Integration
GitHub Actions
yaml# .github/workflows/playwright.yml name: Playwright Tests on: push: branches: [main, master] pull_request: branches: [main, master] jobs: test: timeout-minutes: 60 runs-on: ubuntu-latest steps: - uses: actions/checkout@v4 - uses: actions/setup-node@v4 with: node-version: 20 - name: Install dependencies run: npm ci - name: Install Playwright Browsers run: npx playwright install --with-deps - name: Run Playwright tests run: npx playwright test - uses: actions/upload-artifact@v4 if: always() with: name: playwright-report path: playwright-report/ retention-days: 30
Docker
dockerfileFROM mcr.microsoft.com/playwright:v1.40.0-jammy WORKDIR /app COPY package*.json ./ RUN npm ci COPY . . CMD ["npx", "playwright", "test"]
Debugging
UI Mode
bash# Interactive debugging npx playwright test --ui # Debug specific test npx playwright test --debug login.spec.ts # Step through test npx playwright test --headed --slow-mo=1000
Trace Viewer
typescript// Generate trace test('with trace', async ({ page }) => { await page.context().tracing.start({ screenshots: true, snapshots: true }); // Test actions await page.goto('/'); await page.context().tracing.stop({ path: 'trace.zip' }); }); // View: npx playwright show-trace trace.zip
Console Logs
typescripttest('capture console', async ({ page }) => { page.on('console', msg => console.log(`Browser: ${msg.text()}`)); page.on('pageerror', error => console.error(`Error: ${error.message}`)); await page.goto('/'); });
Best Practices
1. Use Stable Locators
typescript// ✅ Good - Role-based, stable await page.getByRole('button', { name: 'Submit' }).click(); await page.getByLabel('Email').fill('test@example.com'); // ❌ Bad - Fragile, implementation-dependent await page.click('button.btn-primary.submit-btn'); await page.fill('div > form > input:nth-child(3)');
2. Leverage Auto-Waiting
typescript// ✅ Good - Auto-waits await page.click('button'); await expect(page.locator('.result')).toBeVisible(); // ❌ Bad - Manual waits await page.waitForTimeout(2000); await page.click('button');
3. Use Page Object Model
typescript// ✅ Good - Reusable, maintainable const loginPage = new LoginPage(page); await loginPage.login('user', 'pass'); // ❌ Bad - Duplicated selectors await page.fill('[name="username"]', 'user'); await page.fill('[name="password"]', 'pass');
4. Parallel-Safe Tests
typescript// ✅ Good - Isolated test('user signup', async ({ page }) => { const uniqueEmail = `user-${Date.now()}@test.com`; await signUp(page, uniqueEmail); }); // ❌ Bad - Shared state test('user signup', async ({ page }) => { await signUp(page, 'test@test.com'); // Conflicts in parallel });
5. Handle Flakiness
typescript// ✅ Good - Wait for network idle await page.goto('/', { waitUntil: 'networkidle' }); await expect(page.locator('.data')).toBeVisible(); // Configure retries test.describe(() => { test.use({ retries: 2 }); test('flaky test', async ({ page }) => { // Test with auto-retry }); });
Common Patterns
Multi-Page Scenarios
typescripttest('popup handling', async ({ page, context }) => { // Listen for new page const popupPromise = context.waitForEvent('page'); await page.click('a[target="_blank"]'); const popup = await popupPromise; await popup.waitForLoadState(); await expect(popup).toHaveTitle('New Window'); await popup.close(); });
Conditional Logic
typescripttest('handle optional elements', async ({ page }) => { await page.goto('/'); // Close modal if present const modal = page.locator('.modal'); if (await modal.isVisible()) { await page.click('.modal .close-button'); } // Or use count const cookieBanner = page.locator('.cookie-banner'); if ((await cookieBanner.count()) > 0) { await page.click('.accept-cookies'); } });
Data-Driven Tests
typescriptconst testCases = [ { input: 'hello', expected: 'HELLO' }, { input: 'World', expected: 'WORLD' }, { input: '123', expected: '123' }, ]; for (const { input, expected } of testCases) { test(`transforms "${input}" to "${expected}"`, async ({ page }) => { await page.goto('/transform'); await page.fill('input', input); await page.click('button'); await expect(page.locator('.result')).toHaveText(expected); }); }
