The Phpunit task will run your unit tests.
composer require --dev phpunit/phpunit
The task lives under the
phpunit namespace and has following configurable parameters:
# grumphp.yml parameters: tasks: phpunit: config_file: ~ testsuite: ~ group:  always_execute: false
If your phpunit.xml file is located at an exotic location, you can specify your custom config file location with this option.
This option is set to
null by default.
This means that
phpunit.xml.dist are automatically loaded if one of them exist in the current directory.
If you wish to only run tests from a certain Suite.
If you wish to only run tests from a certain Group.
Always run the whole test suite, even if no PHP files were changed.