Matthew Weir O'Phinney has been working with PHPUnit and the SPL (Standard PHP Library) in PHP for a bit now, and he's discovered a way to integrate the two to automate the testing procedure.

I've actually come to enjoy the PHPUnit2 style of tests. In the end, I find that my tests are much less verbose than the way I was performing them with phpt, and I tend to test for failure rather than success; failure should be the exception to the rule. The myriad of 'assert' methods make this relatively easy (though some operate in unexpected ways -- try testing assertSame() on two objects that contain PDO handles, for instance).

One thing that was missing for me was an easy way to run all tests in a directory, ala 'pear run-tests'. However, I was initially disappointed. The demonstrated way to do this is to manually require each test file and add the class contained therein to the test suite. Basically, I was going to need to touch the file every time I added a test class to the suite. Bleh!

So, he set about working up his own solution - a regular expresion-based, recursive class that would locate the testing files and perform the specified actions. He shares the solution with a good bit of example code included with the post.