Testing Patterns

Vitest (Unit + Integration)

• Config lives in apps/web/vite.config.ts (no separate vitest.config)
• Run: npm run test from apps/web/
• Run single file: npx vitest run path/to/file.test.ts

vi.mock Gotcha (IMPORTANT)

vi.mock() is hoisted to the top of the file. You CANNOT reference variables declared above it:

// BAD — will be undefined
const mockFn = vi.fn()
vi.mock('./module', () => ({ doThing: mockFn }))

// GOOD — define inline
vi.mock('./module', () => ({ doThing: vi.fn() }))
import { doThing } from './module'
// Now doThing is the mock — use it for assertions

Rules

• Test behavior, not implementation
• Prefer integration tests over unit tests
• Mock external services, not internal functions
• "close timed out" warning after Vitest is a known nitro issue — ignore

Playwright (E2E)

• Config: apps/web/playwright.config.ts
• Tests: apps/web/e2e/
• Run: npm run test:e2e from apps/web/
• Use page.getByRole(), page.getByText() over CSS selectors