PHPUnit runs all the tests in Drupal 8 and above. Earlier versions of Drupal used the Simpletest module for testing.
PHPUnit in DDEV
Contrib modules: DDEV Drupal Contrib
DDEV Drupal Contrib is a DDEV add-on which makes development on contrib modules easier. That includes but is not limited to running PHPUnit, PHPCS, PHPCBF, and keeping the module repo as the root workspace while having Drupal and its dependencies installed.
