GitHub - HowToTestFrontend/vitest-browser-mode-starter-react: NextJS and Vitest Browser Mode - starter / demo

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Vitest Browser Mode Starter (React)

A minimal starter kit showing how to use Vitest Browser Mode with React.

From How to Test Frontend - full tutorial coming soon on my blog, and course/lessons very soon!

What is Vitest Browser Mode?

Vitest Browser Mode runs your tests in a real browser environment (via Playwright/WebDriver), giving you access to actual browser APIs and more accurate rendering behavior compared to jsdom.

Videos

Preview of how Vitest Browser mode looks when not in headless mode: (You can see the test results and then play with the rendered component after the test)

vitest-browser-mode-ui-demo.mp4

The main app that we are testing: Very simple app, with a few things to test interaction/hiding content:

the-app-we-are-testing-with-vitest-browser-mode.mp4

Info

I've tried to keep this as bare bones as possible so you can easily copy/paste things into your repo to get it all working!

Note

This is using Next.js to scaffold the main app, but this isn't Next.js specific and can apply to any React application.

Setup guide for running the app

yarn install # install package.json deps

yarn test:browser:install # install playwright browsers

yarn dev # run the next dev server to preview the app we are testing, then open http://localhost:3000

But you are probably here to see the Vitest config/commands!

Run either

  • yarn test for regular (not browser mode) tests
  • yarn test:browser for browser mode tests

How the repo is set up

  • We have regular vitest tests (using React Testing Library) which are *.test.tsx files
  • And Browser Mode tests which are *.browser.tsx (note: NOT *.browser.test.tsx)
  • There are two test files - one using regular Vitest (with React Testing Library), and one with the same functionality tested but using Vitest Browser Mode.

Vitest Browser Mode on CI (Github Actions)

  • check out ./.github/workflows/checks.yml to see how everything is installed and running on GitHub Actions. The tests all run there and pass ok! There are also checks for typechecking, formatting etc.

Want to learn more about Vitest Browser Mode

Check out How To Test Frontend.com or the blog post about Vitest Browser Mode on my site!