I asked a similar question before, and got some good answers, but I think it was too general.
http://stackoverflow.com/questions/559484/examples-of-great-software-design-and-implementation
Does anyone know of any open-source projects that demonstrate really good TDD practices, and SOLID principles? TDD and SOLID are widely publicized, but I've never seen it really done myself, I'd just like to get an idea of what it might look like in a project (large or small)?
FitNesse. This is about 50K lines of java code. It was build with TDD, and has about 90% code coverage (probably higher). There is a strong use of SOLID principles throughout. I'm sure you can find some parts you don't like. I often do. But overall the system is very robust. We have thousands of users, and a very small buglist. We make frequent releases, and the sole QA test is: ant testbuild. If the tests pass, we ship it.
Dimdwarf Application Server - It's been written completely with TDD/BDD and by trying to write as clean code as possible (SOLID, good names etc.). Production code is about 4500 SLOC, test code is about 7300 SLOC, code coverage is over 90% and the largest production classes are about 200 LOC.