Module Development

Functional JavaScript Testing for Drupal 8, 9, and 10

In order to execute functional tests that require JavaScript be executed for the feature to work the tests need to be run in a browser that supports JavaScript. This is accomplished by using the WebDriver API in combination with an application like ChromeDriver or Selenium which can remotely control a browser.

The exact setup for running functional tests is dependent on your development environment. We'll walk through a couple of common examples including using Docker (via DDEV-Local) and stand-alone applications.

In this tutorial we'll:

  • Learn how to install and run ChromeDriver and other necessary tools either in a Docker environment, or locally.
  • Configure the relevant PHPUnit environment variables so they contain values appropriate for our specific environment.
  • Execute Drupal's functional JavaScript tests via the phpunit command.

By the end of this tutorial you should be able to install the applications required to run functional JavaScript tests in a browser, and know how to configure PHPUnit to make use of them.