How to handle exceptions raised in other threads when unit testing?

Question

When testing with Visual Studio Team Test unhandled exceptions in tests are caught and reported in the results. So I was kind of surprised to see the test hosting process (V

Answer 1

Generally I try to avoid starting threads in unit tests by injecting a thread provider that, during unit tests, doesn't actually provide a thread, but rather executes syncronously.

Of course, with that approach you can't test any kind of potential contention, or two real code paths running in parallel, but there is a good argument to be made that such a test isn't really a unit test.

When you do test two simultaneous threads, then you need a thread provider which catches exceptions at the end of the the thread and reports them as failures.