Test runner for web applications.
👉 Headless browsers with Puppeteer, Playwright, or Selenium.
🚧 Reports logs, 404s, and errors from the browser.
🔍 Debug opens a real browser window with devtools.
📦 Mock es modules using Import Maps.
🔧 Exposes browser properties like viewport size and dark mode.
⏱ Runs tests in parallel and isolation.
👀 Interactive watch mode.
🏃 Fast development by rerunning only changed tests.
🚀 Powered by esbuild and rollup plugins
See our website for full documentation.
Install the web test runner:
npm i --save-dev @web/test-runner
Do a single test run:
web-test-runner test/**/*.test.js --node-resolve
wtr test/**/*.test.js --node-resolve
Run in watch mode, reloading on file changes:
web-test-runner test/**/*.test.js --node-resolve --watch
wtr test/**/*.test.js --node-resolve --watch
Run with code coverage profiling (this is slower):
web-test-runner test/**/*.test.js --node-resolve --coverage
wtr test/**/*.test.js --node-resolve --coverage
Transform JS to a compatible syntax based on user agent:
web-test-runner test/**/*.test.js --node-resolve --esbuild-target auto
wtr test/**/*.test.js --node-resolve --esbuild-target auto
Check out this step by step guide to get started.
Check out the example projects for a fully integrated setup.
See our website for full documentation.