There is already a thread on the RhinoMocks group.
GenerateMock creates a dynamic mock. The dynamic mock allows calls that are not specified (=expected). If this happens, it just returns null (or the default value of the return type).
Note: Repeat is a specification of the behaviour (like Stub), not the expectation even if specified in an expectation.
If you want to avoid having more then a certain number of calls, you could write:
[Test]
public void uhh_what()
{
var a = MockRepository.GenerateMock<IPrebuiltNotifier>();
a.Expect(x => x.Notify()).Repeat.Once();
a.Expect(x => x.Notify()).Throw(new InvalidOperationException("gotcha"));
a.Notify();
// this fails
a.Notify();
a.VerifyAllExpectations();
}
Or
[Test]
public void uhh_what()
{
var a = MockRepository.GenerateMock<IPrebuiltNotifier>();
a.Notify();
a.Notify();
// this fails
a.AssertWasCalled(
x => x.Notify(),
o => o.Repeat.Once());
}