Testing

Testing patterns using Vitest for backend and Playwright E2E for frontend.

Overview

Backend: Vitest with blackbox testing
Packages: Vitest unit tests (core, react, sentry); CI runs packages-test when packages change
Frontend: Playwright E2E only (no separate unit/integration suites)
E2E: Playwright setup — see E2E Testing

Backend Testing

Setup

// apps/api/src/routes/users.test.ts
import { describe, it, expect } from 'vitest'
import { createApp } from '../app'

describe('GET /users/:id', () => {
  it('returns user when found', async () => {
    const app = await createApp()
    const response = await app.inject({
      method: 'GET',
      url: '/users/123',
    })
    
    expect(response.statusCode).toBe(200)
    expect(response.json()).toMatchObject({
      id: '123',
      email: 'user@example.com',
    })
  })
})

Best Practices

Use blackbox testing (test via HTTP)
Test contracts, not implementation
Use test database (PGLite for embedded Postgres)
Clean up after tests
PGLite linear execution: Vitest runs with fileParallelism: false, maxWorkers: 1, and sequence.concurrent: false to avoid PGLite/WASM instability with parallel workers

Test Utilities

Import from @test/utils/auth-helper.js:

getOrCreateSession(app, email) — Cached JWT by email; reduces magic-link requests when tests share users
createAuthenticatedUser(app) — Returns { token, email } using the session pool
insertTestPasskey(app, jwt) — Inserts a passkey for the authenticated user, returns passkey id (for delete/ownership tests)
getApiKeyToken(app, email) — Creates an API key for the user and returns the raw key
clearSessionPool() — Clears the session cache (called in account.spec.ts afterAll)

Frontend Testing

Frontend apps use Playwright E2E only — no unit or integration test suites. See Frontend Testing and E2E Testing.

E2E Example

// apps/web/e2e/magic-link-auth.spec.ts
import { expect, test } from '@playwright/test'
import { authHelpers } from './auth-helpers'

test('should complete magic link flow', async ({ page }) => {
  await page.goto('/auth/login')
  const response = await authHelpers.sendMagicLink(page)
  expect(response.ok()).toBe(true)
  const token = await authHelpers.extractToken(page)
  if (!token) throw new Error('Failed to extract token')
  await authHelpers.verifyMagicLink(page, token)
  await page.goto('/')
  await expect(page.getByRole('heading', { name: /dashboard/i })).toBeVisible()
})

Frontend Testing - Complete guide for testing React and Next.js applications with real APIs
E2E Testing - Playwright E2E for Next.js and Fastify
API Development - Fastify testing patterns with Vitest and blackbox testing

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