How to clear previous expectations on an object?

Question

I would like to set up a return value

_stubRepository.Stub(Contains(null)).IgnoreArguments().Return(true); 

but then in a specific test, override that expectation to return false.

Something like:

_stubRepository.ClearExpectations();  //<- this does not exist, I'm just making something up _stubRepository.Stub(Contains(null)).IgnoreArguments().Return(false); 

Notice, I do not want the expectation to return false on the second call, I want to override the first expectation.

This would help simplify my testing scenario greatly.

Answer 1

There are three ways:

You can reset the expectations by using BackToRecord

I have to admit that I never really used it because it is awkward.

// clear expectations, an enum defines which _stubRepository.BackToRecord(BackToRecordOptions.All); // go to replay again. _stubRepository.Replay(); 

Edit: Now I use it sometimes, it is actually the cleanest way. There should be an extension method (like Stub) which does it - I think it just got forgotten. I would suggest to write your own.

You can use Repeat.Any()

It 'breaks' the order of the stubbed definition and "overrides" previous definitions. But it's somehow implicit. I use it sometimes because it is easy to write.

_stubRepository.Stub(x => x.Contains(null))   .IgnoreArguments()   .Return(false)   .Repeat.Any(); 

You can create a new mock

Trivial, but explicit and easy to understand. It is only a problem if you want to keep plenty of definitions and only change one call.

_stubRepository = MockRepository.GenerateMock<IRepository>(); _stubRepository.Stub(x => x.Contains(null))   .IgnoreArguments()   .Return(false); 

Answer 2

For these situations, I created a simple RinoMocks extention method to better show the intent of the stub and promote readability.

public static void OverridePrevious<T>(this IMethodOptions<T> options) {     options.Repeat.Any(); } 

So instead of a cryptic call like the following that may require a comment:

[SetUp] public void Setup() {     carStub.Stub(x => x.Model).Return("Model1");     carStub.Stub(x => x.Model).Return("Model2"); }  [Test] public void SomeTest() {     //Arrange     //overrides previous stubs that were setup for the Model property     carStub.Stub(x => x.Model).Return(null).Repeat.Any();      //Act     //Assert } 

You can get a more readable test that better shows the intent of the .Repeat.Any() calls:

carStub.Stub(x => x.Model).Return(null).OverridePrevious();