Testing Overview

Testing Overview

@loewen-digital/fullstack is designed to be testable from the ground up. Every module accepts an in-memory driver, so tests never need a real database, SMTP server, Redis instance, or any external service.

Import

import { createTestStack } from '@loewen-digital/fullstack/testing'

The createTestStack helper

createTestStack creates a fully configured stack with all in-memory drivers pre-wired. Use it as the foundation of your integration tests:

import { describe, it, expect, beforeEach } from 'vitest'
import { createTestStack } from '@loewen-digital/fullstack/testing'

describe('user registration', () => {
  let stack: ReturnType<typeof createTestStack>

  beforeEach(() => {
    stack = createTestStack()
    // Fresh, empty in-memory stack for every test
  })

  it('registers a new user and sends a welcome email', async () => {
    const { auth, mail, db } = stack

    await auth.register({ email: 'alice@example.com', password: 'password123' })

    const user = await db.query.users.findFirst({
      where: (u, { eq }) => eq(u.email, 'alice@example.com'),
    })

    expect(user).toBeDefined()
    expect(user!.email).toBe('alice@example.com')

    mail.assertSent({ to: 'alice@example.com', subject: 'Welcome!' })
  })
})

Using in-memory drivers directly

You don’t need createTestStack — you can configure any module with an in-memory driver:

import { createMail } from '@loewen-digital/fullstack/mail'
import { createCache } from '@loewen-digital/fullstack/cache'

const mail = createMail({ driver: 'memory' })
const cache = createCache({ driver: 'memory' })

Test isolation

Because factory functions create independent instances, each test gets its own isolated module state:

beforeEach(() => {
  // New instance = empty state, no cross-test contamination
  stack = createTestStack()
})

Database helpers

The testing module includes helpers for seeding and clearing the test database:

import { seedDatabase, clearDatabase } from '@loewen-digital/fullstack/testing'

beforeEach(async () => {
  await clearDatabase(stack.db)
  await seedDatabase(stack.db, { users: 5, posts: 10 })
})

What’s in this section

• Fakes — fake implementations for mail, queue, events, and more
• Factories — model factories for generating test data