moq setup not returning expected value

Question

i am using Nunit and Autofac's Moq to setup a test

    [TestFixture]
public class SomeTests
{

    [OneTimeSetUp]
    public void Initialize()
    {

    }
    [Test]
    public void SalaryCheck()
    {                              
        using (var mock = AutoMock.GetLoose())
        {
            // Arrange
            mock.Mock<ICommonServices>().Setup(x => x.AddTwoNumbers(1,2)).Returns(5);
            var sut = mock.Create<SomeManager>(); 
            // Act
            int actul = sut.CalculateSalary(1);


            var expected = 5;


            // Assert
            Assert.AreEqual(expected, actul);

        }
    }
}

CalculateSalary function looks like this

  public int CalculateSalary(int hours)
    {
        var addres = _commonService.AddTwoNumbers(5,3);
        if (addres == 5)
        {
            return addres * hours;
        }
        else
        { 
            return  100;
        }
    }

i want AddTwoNumbers function which is a external dependency, to return 5 no matter what. thats why i am setting it up after mocking it. But when i debug this test it looks like it goes inside the calsulate salary function but returns a "0" for AddTwoNumbers function. which is kind of a default or a null value.

it does not return me 5 i.e. what i set it up to return.

Answer 1

You need to use It.IsAny<int>() i.e.

mock.Mock<ICommonServices>().Setup(x => x.AddTwoNumbers(It.IsAny<int>(),It.IsAny<int>())).Returns(5);

Answer 2

When mocking a method that returns an abstraction, make sure that the type in your call to It.IsAny< YourType >() actually matches the type of the param of the method you are mocking.

Given a method that takes an IEnumerable as a param:

interface IQueueItemRepository {
  IQueueItem GetFirstNotIn(IEnumerable<Guid> guids)
}

In the example below, the .Setup will only ever be invoked when .GetFirstNotIn is called with a Collection as param.

Mock<IQueueItemRepository> queueMock = new Mock<IQueueItemRepository>();

queueMock
    .Setup(x => x.GetFirstNotIn(It.IsAny<Collection<Guid>>()))
    .Returns(new QueueItem());

In other words, if the code you are testing never calls .GetFirstNotIn with a Collection, your .Setup will never be invoked. It may be called numerously throughout your code with an IEnumerable as param, but those calls do not match the .Setup.

So be sure to match your param types to your .Setup types:

Mock<IQueueItemRepository> queueMock = new Mock<IQueueItemRepository>();

queueMock
    .Setup(x => x.GetFirstNotIn(It.IsAny<IEnumerable<Guid>>()))
    .Returns(new QueueItem());