Setup Mock to return the same object, which I send to it?

Question

I want to test some code:

public ViewModel FillClientCreateViewModel(ViewModel model){
    model.Phone = new Phone { Name = "Test"};

    model.Phone = _entityInitializer.FillViewModel(model.Phone);
}

I also want to setup FillViewModel to return the same object as I give to it.

My test:

     entityInitMock.Setup(x => x.FillViewModel(It.IsAny<PhoneViewModel>())).Returns(It.IsAny<PhoneViewModel>());

 var result = TestedInstance.FillClientCreateViewModel(CreateViewModel);

 result.Phone.Name.ShouldBe("Test");

But in this case my test fell - because result.Phone.Name was cleaned by my mock.

How can I setup mock to just give me the same object which i give to it.

score 18 · Accepted Answer · edited Feb 08 '22 at 19:54

18

entityInitMock.Setup(x => x.FillViewModel(It.IsAny<PhoneViewModel>()))
    .Returns((PhoneViewModel m) => m);

The Moq QuickStart is a great reference for similar questions.

edited Feb 08 '22 at 19:54

Johann

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answered Jan 14 '12 at 02:03

TrueWill

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how do you make that work in ReturnsAsync ? I get "Cannot convert lambda expression to type ___ because it is not a delegate type". – johni Apr 22 '17 at 14:53
@johni See http://stackoverflow.com/questions/31527394/moq-returnsasync-with-parameters and http://stackoverflow.com/questions/21253523/setup-async-task-callback-in-moq-framework – TrueWill Apr 24 '17 at 13:40
Good answer. Such nuances in TDD scenarios are important to cover to get all the nuts and bolts in place for detailed TDD. Thanks. – Tore Aurstad Oct 11 '18 at 09:06

Setup Mock to return the same object, which I send to it?

1 Answers1