When doing TDD or at least unit testing, it is necessary to know how much of your code is covered by tests and, more importantly, which code isn’t. Since we migrated to NUnit the integrated Visual Studio 2010 code coverage does not do the job anymore for us (although I’ve found several articles on how to enable it, for some reason I couldn’t get it running).
There are two tools that you can use instead – one of them is NCover, which is a great tool but not free. The other one is PartCover, which is a free code coverage tool. I’ve opted to go with the latter. The main problem with PartCover is the almost non-existent documentation. After several hours of trying out different combinations of options I finally got it running and it does it job really good.