Autobahn WebSockets protocol compliance test suite
I'm nearing the end of my WebSockets implementation for The Server Framework and have been dealing with various protocol compliance issues. Whilst I have decent unit test coverage I haven't, yet, sat down and produced compliance specific unit tests which walk through the various parts of the (ever changing) draft RFC and test each aspect. Looking back, I probably should have taken this approach even though the RFC was fluid. Anyway. One of the people involved in the WebSockets Working Group has a nice set of compliance tests for their implementation and they have made these tests are freely available; so I've been using them! They've really helped nail a few subtle issues in my implementation (and one or two not so subtle issues!).