In an effort to increase quality of SMW (by reducing the amount of bugs) and facilitating future development (by regression detection) I've been adding unit tests to SMW. Not that many, but at least we now got some coverage. Nischyan has also been added a bunch as part of his GSoC project. And I'm now looking into getting a CI server up running these unit tests and the Selenium tests Benedikt Kämpgen wrote over a year ago.
I encourage everyone concerned with the quality of SMW to contribute their tests in a form that can be used by people working on the software. It's nice if you spot regressions on your site between releases, but it's way better to not have these regressions happen in the first place :)
If anyone has or questions on how to create them, I'd be happy to help you getting them into SMW.
Jeroen De Dauw
Don't panic. Don't be evil.