Pex: How to indicate in a parameterized test that I expect an exception under certain conditions?

I'm just getting started with Pex and running into an issue as described in the title. It seems that any parameterized tests generated by Pex or added by hand will create failing test cases for any inputs that cause an exception to be raised. Is there a way for me to indicate that cert开发者_如何学Cain inputs should raise exceptions, and therefore not cause a specific test to fail?

If you select the failing in test there is an 'Allow Exception' option which tells pex that the exception is correct behaviour.