Testee (in common with all of my ExpressionEngine add-ons) is no longer officially supported.
Check out the wiki for installation and usage instructions, and feel free to fork the repo if you'd like to make some changes or improvements (it's distributed under a liberal open source license).
Hopefully this will be everything you need to use this add-on in your projects, but if not please don't email me asking for support; I don't even have ExpressionEngine installed locally any more.
Testee makes unit testing and test-driven development of ExpressionEngine 2 add-ons easy.
Behind the scenes, Testee takes care of all the hard work of replacing ExpressionEngine’s built-in objects with mock objects, allowing you to get on with writing tests safe in the knowledge that you’re not about to destroy your site.
Testee uses the PHP SimpleTest framework to run your tests, and interpret the results. If you know how to write a SimpleTest unit test, you already know how to write a Testee unit test; and if you don’t, SimpleTest is well documented.