Is TypeMock Isolator: WillThrow () expiring across unit test boundaries?

Question

I have two unit tests that use TypeMock Isolator to isolate and fake a method from asp.net SqlMembershipProvider.

In test 1, I have:

Isolate.WhenCalled( () => Membership.CreateUser(...))) .WithExactArguments() .WillThrow(new Exception()); 

In test 2, I have:

  Isolate.WhenCalled( () => Membership.CreateUser(...))) .WithExactArguments() .WillReturn(new MembershipUser(...)); 

When I run each test on its own, they both pass successfully.

When I run both tests, test number 1 starts first and passes and then tests number 2 and fails with the exception caused by test 1.

Why did the WillThrow() command in test 1 bleed for test 2? After all, test 2 explicitly defines a different behavior - WillReturn() ?

Answer 1

If TypeMock's behavior is bleeding between tests, then the first thing to check is cleaning between tests. You can do this explicitly by calling Isolater.CleanUp() or using the preferred approach , which should decorate either the testing methods or the test class itself with the [Isolated] attribute.