Testing is using phpunit. See:
http://www.phpunit.de

Install like so (might need sudo):
pear channel-discover pear.phpunit.de
pear install phpunit/PHPUnit

And run from this directory like:
phpunit --configuration tests.xml

This does use the current database set in config.php.  They're generally not 
descructive, but the content stuff is a bit messy.