happo-playwright

happo-playwright

This library can be used together with Playwright to get Happo screenshots integrated with integration/end-to-end tests.

Installation & setup

First, install the library along with the happo.io and happo-e2e libraries:

npm install --save-dev happo.io happo-e2e happo-playwright

Configure Happo in a .happo.js configuration file. The below config file is a minimal example.

// .happo.js
const { RemoteBrowserTarget } = require('happo.io');

module.exports = {
  targets: {
    chrome: new RemoteBrowserTarget('chrome', {
      viewport: '1024x768',
    }),
  },
};

Spec file setup

Below is an example Playwright spec file. It takes a screenshot of a Hero image on an imaginary page.

// tests/test.spec.js
import { test } from 'happo-playwright';

test('start page', async ({ page, happoScreenshot }) => {
  await page.goto('http://localhost:7676');

  const heroImage = page.locator('.hero-image');

  await happoScreenshot(heroImage, {
    component: 'Hero Image',
    variant: 'default',
  });
});

With Playwright fixtures

If you're using Playwright fixtures, you can mix happo-playwright in with mergeTests.

Here's an example of how to do this:

// tests/test.js
import { test as happoTest } from 'happo-playwright';
import { test as base, mergeTests } from '@playwright/test';

const baseTest = base.extend({
  myFixture: async ({}, use) => {
    await use('my fixture value');
  },
});

export const test = mergeTests(baseTest, happoTest);

Then in your Playwright test file, you can use the test function as usual:

// tests/test.spec.js
import { test } from './test';

test('start page', async ({ page, happoScreenshot }) => {
  await page.goto('http://localhost:7676');

  const heroImage = page.locator('.hero-image');

  await happoScreenshot(heroImage, {
    component: 'Hero Image',
    variant: 'default',
  });
});

Usage

When you run your tests, you need to wrap the command with the happo-e2e script, like this:

npx happo-e2e -- npx playwright test

This will ensure that Happo combines all the screenshots taken into a single job. When the process exits, you'll see a url logged at the end. Use this to inspect your screenshots.