When it comes to unit testing, Visual Studio has always been tightly tied to the MSTest framework. The inclusion of a unit test framework inside Visual Studio has been excellent. It has encouraged developers to improve their quality by writing tests to prove code functions as expected. On the flip side, many developers regard MSTest as an inferior unit test framework when compared to NUnit, XUnit, MbUnit, and other frameworks. The problem stems from the fact that MSTest does so much more than unit testing and as a result suffers from poor speed and bloat. Additionally, its assertion methods are fragmented across multiple classes and it has a cumbersome approach to data-driven tests and expected exceptions. MSTest has also been tied to the release cycle of Visual Studio, so updates have been very slow and it lags behind when compared to the other test frameworks.

Microsoft is ending the tight coupling between Visual Studio and MSTest by making the unit test framework...