Testing in pipelines: lint, unit, integration and the gate

$ npm install --save-dev eslint@9 @eslint/js@9 globals

// eslint.config.js
import js from '@eslint/js'
import globals from 'globals'

export default [
  js.configs.recommended,
  { languageOptions: { globals: globals.node } },
]

$ npx eslint .
src/bad.js
  3:26  error  'sum' is assigned a value but never used  no-unused-vars
  4:10  error  'totl' is not defined                     no-undef

✖ 2 problems (2 errors, 0 warnings)
$ echo $?
1

$ node --test --experimental-test-coverage --test-coverage-lines=80 'test/*.test.js'
ℹ Error: 69.23% line coverage does not meet threshold of 80%.
ℹ start of coverage report
ℹ  app.js   |  69.23 |    87.50 |  100.00 | 12-19

test('GET /price answers with the total, or 400 for a bad amount', async () => {
  const server = createApp().listen(0)
  const { port } = server.address()
  const ok = await fetch(`http://localhost:${port}/price?amount=100`)
  assert.deepEqual(await ok.json(), { total: 118 })
  const bad = await fetch(`http://localhost:${port}/price?amount=-1`)
  assert.equal(bad.status, 400)
  server.close()
})

$ npm run test:coverage
ℹ pass 4
ℹ fail 0
ℹ  app.js   |  96.15 |    90.91 |  100.00 | 19

// test/integration/api.test.js
import { test, before, after } from 'node:test'
import assert from 'node:assert/strict'
import { spawn } from 'node:child_process'

const PORT = 4567
const base = `http://localhost:${PORT}`
let server

before(async () => {
  server = spawn(process.execPath, ['src/server.js'], { env: { ...process.env, PORT: String(PORT) } })
  for (let i = 0; i < 50; i++) {
    try {
      if ((await fetch(`${base}/health`)).ok) return
    } catch {
      // not listening yet: wait and retry
    }
    await new Promise((r) => setTimeout(r, 100))
  }
  throw new Error('server did not start within 5 seconds')
})

after(() => server.kill())

test('GET /price returns the total with tax', async () => {
  const res = await fetch(`${base}/price?amount=100`)
  assert.equal(res.status, 200)
  assert.deepEqual(await res.json(), { total: 118 })
})

test('unknown paths return 404', async () => {
  assert.equal((await fetch(`${base}/nope`)).status, 404)
})

$ node --test 'test/integration/*.test.js'
✔ GET /price returns the total with tax (310.217185ms)
✔ GET /price rejects a bad amount with 400 (31.433313ms)
✔ unknown paths return 404 (15.854698ms)

$ npm pkg set scripts.test="node --test 'test/*.test.js'" \
    scripts.test:integration="node --test 'test/integration/*.test.js'" \
    scripts.test:coverage="node --test --experimental-test-coverage --test-coverage-lines=80 'test/*.test.js'"

integration:
  needs: [lint, unit]
  runs-on: ubuntu-latest
  services:
    postgres:
      image: postgres:17
      env:
        POSTGRES_PASSWORD: test
      ports: ['5432:5432']
      options: >-
        --health-cmd "pg_isready -U postgres"
        --health-interval 5s
        --health-timeout 5s
        --health-retries 10
  env:
    DATABASE_URL: postgres://postgres:test@localhost:5432/postgres
  steps:
    - uses: actions/checkout@v7
    - uses: actions/setup-node@v7
      with:
        node-version: 22
        cache: npm
    - run: npm ci
    - run: npm run test:integration