I\'m about to embark on some large Python-based App Engine projects, and I think I should check with Stack Overflow\'s \"wisdom of crowds\" before committing to a unit-testing s
I use GAEUnit for my Google App Engine App and I am quite happy with the speed of the tests. The thing that I like about GAEUnit,and I am sure Webtest does it, is that it creates its own version for stubs of everything for testing leaving your "live" versions alone for testing.
So your datastore that you may be using for development will be left as is when you run your GAETests.