SimpleTest
Last modified: March 8, 2009 - 03:11
SimpleTest is Drupal's custom testing framework. During the Drupal 7 development cycle SimpleTest has become an integral part of the workflow. It has significantly enhanced the the way core is developed and made it possible to make major API enhancements with confidence.
Drupal 7 HEAD is much more stable than any release we [have] ever had. -chx
Drupal 7 has seen major benefits from embracing the testing framework.