Invocation on a non-virtual method when object casted to interface is wrong

[kostadinmarinov]

This is a problem only in master. In release v4.2.1312 it's not met.

You have a concrete class which implements an interface.The interface's members are implemented as NON-VIRTUAL in the concrete class. Then you create a mock of the concrete class. If the mock's object is passed as the concrete class, there is no problem to call the method - its concrete implementation is used. However, if you pass the object as the interface, then the method invocation is mocked and doesn't use the concrete implementation.

However, this behavior is unexpected when the original mock was created on the concrete type, it should work based on its interface not as it's used.

The problem is reproducible with the following code:

public class A : IA
{
public void Foo()
{
Debug.WriteLine("Foo() called.");
}
}

public interface IA
{
    void Foo();
}

[TestFixture]
public class TestFixture
{
    [Test]
    public void Test()
    {
        Mock<A> mock = new Mock<A>(MockBehavior.Strict);

        mock.Object.Foo();
        ((IA)mock.Object).Foo();    // throws  Moq.MockException : IX.Foo() invocation failed with mock behavior Strict.
    }
}

[delta-emil]

FYI: This was caused by commit 162a543
However, undoing that change breaks test ShouldBeAbleToCastToImplementedInterface

[stakx]

Fixed in Moq 4.7.58.