@web/test-runner is our recommended test runner for Snowpack projects. Read more about why we recommend @web/test-runner in our Snowpack Testing Guide.

To use @web/test-runner in your project, follow the instructions here and make sure that you add the Snowpack plugin to your config file:

// web-test-runner.config.js
module.exports = {
  plugins: [require('@snowpack/web-test-runner-plugin')()],
};

See an example setup in one of our Create Snowpack App starter templates.