Playwright Best Practices

Playwright Best Practices

This skill provides comprehensive guidance for all aspects of Playwright test development, from writing new tests to debugging and maintaining existing test suites.

Activity-Based Reference Guide

Consult these references based on what you're doing:

Writing New Tests

When to use: Creating new test files, writing test cases, implementing test scenarios

Activity	Reference Files
Writing E2E tests	test-suite-structure.md, locators.md, assertions-waiting.md
Writing component tests	component-testing.md, test-suite-structure.md
Writing API tests	api-testing.md, test-suite-structure.md
Writing GraphQL tests	graphql-testing.md, api-testing.md
Writing visual regression tests	visual-regression.md, canvas-webgl.md
Structuring test code with POM	page-object-model.md, test-suite-structure.md
Setting up test data/fixtures	fixtures-hooks.md, test-data.md
Handling authentication	authentication.md, authentication-flows.md
Testing date/time features	clock-mocking.md
Testing file upload/download	file-operations.md, file-upload-download.md
Testing forms/validation	forms-validation.md
Testing drag and drop	drag-drop.md
Testing accessibility	accessibility.md
Testing security (XSS, CSRF)	security-testing.md
Using test annotations	annotations.md
Using test tags	test-tags.md
Testing iframes	iframes.md
Testing canvas/WebGL	canvas-webgl.md
Internationalization (i18n)	i18n.md
Testing Electron apps	electron.md
Testing browser extensions	browser-extensions.md

Mobile & Responsive Testing

When to use: Testing mobile devices, touch interactions, responsive layouts

Activity	Reference Files
Device emulation	mobile-testing.md
Touch gestures (swipe, tap)	mobile-testing.md
Viewport/breakpoint testing	mobile-testing.md
Mobile-specific UI	mobile-testing.md, locators.md

Real-Time & Browser APIs

When to use: Testing WebSockets, geolocation, permissions, multi-tab flows

Activity	Reference Files
WebSocket/real-time testing	websockets.md
Geolocation mocking	browser-apis.md
Permission handling	browser-apis.md
Clipboard testing	browser-apis.md
Camera/microphone mocking	browser-apis.md
Multi-tab/popup flows	multi-context.md
OAuth popup handling	third-party.md, multi-context.md

Debugging & Troubleshooting

When to use: Test failures, element not found, timeouts, unexpected behavior

Activity	Reference Files
Debugging test failures	debugging.md, assertions-waiting.md
Fixing flaky tests	flaky-tests.md, debugging.md, assertions-waiting.md
Debugging flaky parallel runs	flaky-tests.md, performance.md, fixtures-hooks.md
Ensuring test isolation / avoiding state leak	flaky-tests.md, fixtures-hooks.md, performance.md
Fixing selector issues	locators.md, debugging.md
Investigating timeout issues	assertions-waiting.md, debugging.md
Using trace viewer	debugging.md
Debugging race conditions	flaky-tests.md, debugging.md, assertions-waiting.md
Debugging console/JS errors	console-errors.md, debugging.md

Error & Edge Case Testing

When to use: Testing error states, offline mode, network failures, validation

Activity	Reference Files
Error boundary testing	error-testing.md
Network failure simulation	error-testing.md, network-advanced.md
Offline mode testing	error-testing.md, service-workers.md
Service worker testing	service-workers.md
Loading state testing	error-testing.md
Form validation testing	error-testing.md

Multi-User & Collaboration Testing

When to use: Testing features involving multiple users, roles, or real-time collaboration

Activity	Reference Files
Multiple users in one test	multi-user.md
Real-time collaboration	multi-user.md, websockets.md
Role-based access testing	multi-user.md
Concurrent action testing	multi-user.md

Architecture Decisions

When to use: Choosing test patterns, deciding between approaches, planning test architecture

Activity	Reference Files
POM vs fixtures decision	pom-vs-fixtures.md
Test type selection	test-architecture.md
Mock vs real services	when-to-mock.md
Test suite structure	test-suite-structure.md

Framework-Specific Testing

When to use: Testing React, Angular, Vue, or Next.js applications

Activity	Reference Files
Testing React apps	react.md
Testing Angular apps	angular.md
Testing Vue/Nuxt apps	vue.md
Testing Next.js apps	nextjs.md

Refactoring & Maintenance

When to use: Improving existing tests, code review, reducing duplication

Activity	Reference Files
Refactoring to Page Object Model	page-object-model.md, test-suite-structure.md
Improving test organization	test-suite-structure.md, page-object-model.md
Extracting common setup/teardown	fixtures-hooks.md
Replacing brittle selectors	locators.md
Removing explicit waits	assertions-waiting.md
Creating test data factories	test-data.md
Configuration setup	configuration.md

Infrastructure & Configuration

When to use: Setting up projects, configuring CI/CD, optimizing performance

Activity	Reference Files
Configuring Playwright project	configuration.md, projects-dependencies.md
Setting up CI/CD pipelines	ci-cd.md, github-actions.md
GitHub Actions setup	github-actions.md
GitLab CI setup	gitlab.md
Other CI providers	other-providers.md
Docker/container setup	docker.md
Global setup & teardown	global-setup.md
Project dependencies	projects-dependencies.md
Optimizing test performance	performance.md, test-suite-structure.md
Configuring parallel execution	parallel-sharding.md, performance.md
Isolating test data between workers	fixtures-hooks.md, performance.md
Test coverage	test-coverage.md
Test reporting/artifacts	reporting.md

Advanced Patterns

When to use: Complex scenarios, API mocking, network interception

Activity	Reference Files
Mocking API responses	test-suite-structure.md, network-advanced.md
Network interception	network-advanced.md, assertions-waiting.md
GraphQL mocking	network-advanced.md
HAR recording/playback	network-advanced.md
Custom fixtures	fixtures-hooks.md
Advanced waiting strategies	assertions-waiting.md
OAuth/SSO mocking	third-party.md, multi-context.md
Payment gateway mocking	third-party.md
Email/SMS verification mocking	third-party.md
Failing on console errors	console-errors.md
Security testing (XSS, CSRF)	security-testing.md
Performance budgets & Web Vitals	performance-testing.md
Lighthouse integration	performance-testing.md
Test annotations (skip, fixme)	annotations.md
Test tags (@smoke, @fast)	test-tags.md
Test steps for reporting	annotations.md

Quick Decision Tree

What are you doing?
│
├─ Writing a new test?
│  ├─ E2E test → core/test-suite-structure.md, core/locators.md, core/assertions-waiting.md
│  ├─ Component test → testing-patterns/component-testing.md
│  ├─ API test → testing-patterns/api-testing.md, core/test-suite-structure.md
│  ├─ GraphQL test → testing-patterns/graphql-testing.md
│  ├─ Visual regression → testing-patterns/visual-regression.md
│  ├─ Visual/canvas test → testing-patterns/canvas-webgl.md, core/test-suite-structure.md
│  ├─ Accessibility test → testing-patterns/accessibility.md
│  ├─ Mobile/responsive test → advanced/mobile-testing.md
│  ├─ i18n/locale test → testing-patterns/i18n.md
│  ├─ Electron app test → testing-patterns/electron.md
│  ├─ Browser extension test → test