AutoMocker with Setup not working properly

Question

I am trying to use Moq.Automock in one of my projects, which I have not used before. Please see the code below:

[TestFixture]
public class BusinessLayerTests
{
    List<Denomination> expectedDenominations;

    AutoMocker mocker = new AutoMocker();
    UKCurrency Currency;
    IDenominationFactory DenominationFactory;

    [OneTimeSetUp]
    public void Initialize()
    {
        Currency = mocker.CreateInstance<UKCurrency>();
        DenominationFactory = mocker.CreateInstance<DenominationFactory>();        
        mocker.Setup<UKCurrency>(x => x.CurrencyDenominations()).Returns(CurrencyDenominations());
    }

    public System.Collections.Generic.IEnumerable<decimal> CurrencyDenominations()
    {
        yield return 50M;
    }
}

I believe the code above shows that I have created a mock object called: Currency. I believe the line starting: mocker.Setup should ensure that the local method called: CurrencyDenominations is called. However, this does not happen. The method called: CurrencyDenominations in UKCurrency is called.

What am I doing wrong?

Answer 1

You need to get the underlying mock and apply the setup on that.

[OneTimeSetUp]
public void Initialize() {
    Currency = mocker.CreateInstance<UKCurrency>();
    DenominationFactory = mocker.CreateInstance<DenominationFactory>();
    var currencyMock = mocker.GetMock<UKCurrency>();
    currencyMock.Setup(_ => _.CurrencyDenominations()).Returns(CurrencyDenominations());
}

provided UKCurrency.CurrencyDenominations is virtual and able to be overridden.