Web App Testing
Discover and test everything. Leave no route untested.
1. Deep Audit Approach
Discovery First
| Target | How to Find |
|---|---|
| Routes | Scan app/, pages/, router files |
| API endpoints | Grep for HTTP methods |
| Components | Find component directories |
| Features | Read documentation |
Systematic Testing
- Map - List all routes/APIs
- Scan - Verify they respond
- Test - Cover critical paths
2. Testing Pyramid
/\ E2E (Few)
/ \ Critical user flows
/----\
/ \ Integration (Some)
/--------\ API, data flow
/ \
/------------\ Unit/Component (Many)
Individual pieces
3. E2E Test Principles
What to Test
| Priority | Tests |
|---|---|
| 1 | Happy path user flows |
| 2 | Authentication flows |
| 3 | Critical business actions |
| 4 | Error handling |
Best Practices
| Practice | Why |
|---|---|
| Use data-testid | Stable selectors |
| Wait for elements | Avoid flaky tests |
| Clean state | Independent tests |
| Avoid impl details | Test user behavior |
4. Playwright Configuration
Recommended Settings
| Setting | Recommendation |
|---|---|
| Retries | 2 on CI |
| Trace | on-first-retry |
| Screenshots | on-failure |
| Video | retain-on-failure |
Core Concepts
| Concept | Use |
|---|---|
| Page Object Model | Encapsulate page logic |
| Fixtures | Reusable test setup |
| Assertions | Built-in auto-wait |
| Trace Viewer | Debug failures |
5. Test Organization
File Structure
tests/
├── e2e/ # Full user flows
├── integration/ # API, data
├── component/ # UI units
└── fixtures/ # Shared data
Naming Convention
| Pattern | Example |
|---|---|
| Feature-based | login.spec.ts |
| Descriptive | user-can-checkout.spec.ts |
6. API Testing
Coverage Areas
| Area | Tests |
|---|---|
| Status codes | 200, 400, 404, 500 |
| Response shape | Matches schema |
| Error messages | User-friendly |
| Edge cases | Empty, large, special chars |
7. CI Integration
Pipeline Steps
- Install dependencies
- Install browsers (
npx playwright install) - Run tests
- Upload artifacts (traces, screenshots)
Parallelization
| Strategy | Use |
|---|---|
| Per file | Playwright default |
| Sharding | Large suites |
| Workers | Multiple browsers |
8. Anti-Patterns
| ❌ Don't | ✅ Do |
|---|---|
| Test implementation | Test behavior |
| Hardcode waits | Use auto-wait |
| Skip cleanup | Isolate tests |
| Ignore flaky tests | Fix root cause |
9. Recommended Testing Standards
Required Coverage
| Vertical | Minimum Coverage |
|---|---|
| Auth | 90%+ |
| Payment | 95%+ |
| Core Features | 80%+ |
Test Types Required
- Unit tests (Jest/Vitest)
- Integration tests (Supertest)
- E2E tests (Playwright)
- Visual regression (optional)
Remember: E2E tests are expensive. Use them for critical paths only.