I wonder how many others didn't think to scroll down further on the Pex download page, and find this link? Visual Studio 2010 Moles - Isolation Framework for .NET. Moles is available for free, while the full Pex environment requires MSDN.

Once again I've learned the hard way that it pays to read the release notes. After installing Pex v0.91.x, suddenly I was having trouble running my tests in a particular solution. It has been driving me nuts - Visual Studio was throwing "object reference not set to an instance of an object" errors every time I tried to run tests, and the Test View was refusing to load any test names.

Finally, I noticed that I had a few tests that were still instrumented with HostType "pex" instead of "moles". I changed these around, and still got the error. Closed Visual Studio, restarted, and voìla, the tests can run, and Test View is populated again.

Pex and Moles - Release Notes

A few weeks ago I stumbled upon a tool called Pex from the Microsoft Research Labs: "Pex finds interesting input-output values of your methods, which you can save as a small test suite with high code coverage." Not having much time to spend exploring it, I was fortunate to have time to attend a Twin Cities Developers Guild meeting tonight and hear a talk on on how to use the tool, which now has me jump started. First a few highlights of what I learned (without cribbing too much from Jason Bock's presentation), and then sample results from the method in my last post.