@mozilla/jest-environment-puppeteer

jest-environment-puppeteer

Run your tests using Jest & Puppeteer 🎪✨

npm install jest-environment-puppeteer puppeteer

Usage

Update your Jest configuration:

{
  "globalSetup": "jest-environment-puppeteer/setup",
  "globalTeardown": "jest-environment-puppeteer/teardown",
  "testEnvironment": "jest-environment-puppeteer"
}

Use Puppeteer in your tests:

describe('Google', () => {
  beforeAll(async () => {
    await page.goto('https://google.com')
  })

  it('should display "google" text on page', async () => {
    const text = await page.evaluate(() => document.body.textContent)
    expect(text).toContain('google')
  })
})

API

global.browser

Give access to the Puppeteer Browser.

it('should open a new page', async () => {
  const page = await browser.newPage()
  await page.goto('https://google.com')
})

global.page

Give access to a Puppeteer Page opened at start (you will use it most of time).

it('should fill an input', async () => {
  await page.type('#myinput', 'Hello')
})

global.context

Give access to a browser context that is instantiated when the browser is launched. You can control whether each test has its own isolated browser context using the browserContext option in your jest-puppeteer.config.js.

global.jestPuppeteer.debug()

Put test in debug mode.

• Jest is suspended (no timeout)
• A debugger instruction to Chromium, if Puppeteer has been launched with { devtools: true } it will stop

it('should put test in debug mode', async () => {
  await jestPuppeteer.debug()
})

global.jestPuppeteer.resetPage()

Reset global.page

beforeEach(async () => {
  await jestPuppeteer.resetPage()
})

global.jestPuppeteer.resetBrowser()

Reset global.browser, global.context, and global.page

beforeEach(async () => {
  await jestPuppeteer.resetBrowser()
})

jest-puppeteer.config.js

You can specify a jest-puppeteer.config.js at the root of the project or define a custom path using JEST_PUPPETEER_CONFIG environment variable. It should export a config object or a Promise for a config object.

• launch <[object]> All Puppeteer launch options can be specified in config. Since it is JavaScript, you can use all stuff you need, including environment.
• connect <[object]> All Puppeteer connect options can be specified in config. This is an alternative to launch config, allowing you to connect to an already running instance of Chrome.
• browserContext <[string]>. By default, the browser context (cookies, localStorage, etc) is shared between all tests. The following options are available for browserContext:
  • default Each test starts a tab, so all tests share the same context.
  • incognito Each tests starts an incognito window, so all tests have a separate, isolated context. Useful when running tests that could interfere with one another. (Example: testing multiple users on the same app at once with login, transactions, etc.)
• exitOnPageError <[boolean]> Exits page on any global error message thrown. Defaults to true.
• server <[Object]> Server options allowed by jest-dev-server

Example 1

// jest-puppeteer.config.js
module.exports = {
  launch: {
    dumpio: true,
    headless: process.env.HEADLESS !== 'false',
  },
  server: {
    command: 'node server.js',
    port: 4444,
    launchTimeout: 10000,
    debug: true,
  },
}

Example 2

This example uses an already running instance of Chrome by passing the active web socket endpoint to connect. This is useful, for example, when you want to connect to Chrome running in the cloud.

// jest-puppeteer.config.js
const fetch = require('node-fetch')
const dockerHost = 'http://localhost:9222'

async function getConfig() {
  const response = await fetch(`${dockerHost}/json/version`)
  const browserWSEndpoint = (await response.json()).webSocketDebuggerUrl
  return {
    connect: {
      browserWSEndpoint,
    },
    server: {
      command: 'node server.js',
      port: 3000,
      launchTimeout: 10000,
      debug: true,
    },
  }
}

module.exports = getConfig()

Inspiration

Thanks to Fumihiro Xue for his great Jest example.

License

MIT