Issues with unit tests

[gps035]

I saw this library the other day, and thought it would be useful for unit testing, but ran into some issues.
I've added a commit with some new tests that should demonstrate the issues.

It seems that whenever the Assert class (from Microsoft.VisualStudio.TestTools.UnitTesting) is used within a PoseContext.Isolate entry point, a InvalidProgramException is thrown with the message Common Language Runtime detected an invalid program.

I'm not sure why that is, but I tried with another assertion library, Shouldly, and this time the assertions work, but the problem is that any exceptions from failed assertions (any exceptions actually), are wrapped in a TargetInvocationException. This means that the failed unit tests have error messages that are not as useful as they could be.

I've added another commit that simply catches that exception and rethrows the inner exception, which solves that particular issue, but I don't know if that is ideal. I'm not very familiar with the project and don't know if the original exception is needed or useful.

Perhaps the best way to deal with this would be to do all asserting outside of the Isolate method.

[tonerdo]

@gps035 Thanks for the intention to contribute. Usually Assert statements shouldn't be isolated, you should instead isolate specific methods and use the result in a pure assert. I will look into the exception thrown when Assert is isolated, thanks for that.