In my experience, the unittest module included with the Python
standard library works just fine. The important part of unittesting
GUI applications is not to start the main loop, but you don't need a
specific tool for that.
Cheers, Frank
In my experience testing that a button actually invokes its event
handler is not worth the effort. In our tests (for Task Coach, an open
source task manager developed in python and wxPython) we simply invoke
the event handler with a dummy event if needed.
See this article:
http://www.objectmentor.com/resources/articles/TheHumbleDialogBox.pdf
Cheers, Frank