Last updated April 2, 2021

When running tests with PHPUnit we need to specify a phpunit.xml file that contains the configuration that we want to use. Often times (and in much of the existing documentation) the recommendation is to copy the core/phpunit.xml.dist file to core/phpunit.xml and make your changes there. And this works fine, until something like a composer install or composer update ends up deleting your modified file. Instead, you should copy the file to a different location in your project and commit it to your version control repository.

In this tutorial we'll:

  • Learn how to move, and modify, the phpunit.xml.dist file provided by Drupal core
  • Understand the benefits of doing so
  • Demonstrate how to run phpunit with an alternative configuration file

By the end of this tutorial you should be able to commit your phpunit.xml configuration file to your project's Git repository and ensure it doesn't get accidentally deleted.