Don’t get me wrong there is nothing wrong with NUnit and it may or may not be superior to MSTest. I am currently a user of MSTest in my personal projects and the jury is still out if I will use it at work. I just never found a truly compelling reason to use one over the other. MSTest comes well integrated in Visual Studio out the box and had the least amount of pain in terms of setup and getting a test project going. With the release of VS 2012, the playing field has been leveled a bit more as I can run an NUnit test through the Test Explorer, just like an MSTest/VSTest. This is accomplished by adding a simple NuGet package to the test project, NUnit Test Adapter for VS2012 and VS2013.
Anyway, another compelling reason to choose one over the other that I keep bumping into is being able to run tests in parallel. MSTest has the ability to run tests in parallel, but the implementation doesn’t sound solid by some of the posts I have been reading. VSTest, the VS 2012+ default test engine, does not run tests in parallel. NUnit does not support parallel either although the community has been waiting on the next version that is supposed to have this feature…if it ever is released.
Actually, the reason for this post is I was doing a little reading up on PNUnit. It is supposed to run NUnit tests in parallel. Not sure how good the project is, but their website started discussing the need to run their tests across Windows and Linux. Ah..ha! there you go. If you need to run cross platform tests you may lean towards NUnit and with PNUnit providing parallelization you may lean a little bit more.
I guess I am going to toy around more with NUnit VS2012 integration to see if I can somehow get as comfortable a workflow as I do running NUnit tests in VS2013. I will also toy around with PNUnit as this would have an immediate impact on my decision for automation engine at work.