Partial mocking of class with Moq

Question

I want to mock only the GetValue method of the following class, using Moq:

public class MyClass
{
    public virtual void MyMethod()
    {
        int value = GetValue();
        Console.WriteLine("ORIGINAL MyMethod: " + value);
    }

    internal virtual int GetValue()
    {
        Console.WriteLine("ORIGINAL GetValue");
        return 10;
    }
}

I already read a bit how this should work with Moq. The solution that I found online is to use the CallBase property, but that doesn't work for me.

This is my test:

[Test]
public void TestMyClass()
{
     var my = new Mock<MyClass> { CallBase = true };
     my.Setup(mock => mock.GetValue()).Callback(() => Console.WriteLine("MOCKED GetValue")).Returns(999);
     my.Object.MyMethod();
     my.VerifyAll();
 }

I would expect that Moq uses the existing implementation of MyMethod and calls the mocked method, resulting in the following output:

ORIGINAL MyMethod: 999
MOCKED GetValue

but that's what I get :

ORIGINAL GetValue
ORIGINAL MyMethod: 10

and then

Moq.MockVerificationException : The following setups were not matched: MyClass mock => mock.GetValue()

I got the feeling, that I misunderstood something completely. What am I missing here? Any help would be appreciated

possible duplicate of [When mocking a class with Moq, how can I CallBase for just specific methods?](http://stackoverflow.com/questions/2822947/when-mocking-a-class-with-moq-how-can-i-callbase-for-just-specific-methods) — StriplingWarrior, Jun 13 '12 at 15:14
If you make your `GetValue` method `public` instead of `internal` it works. I don't know why maybe this is a limitation of castle dynamic proxy, or is it a bug a Moq, or this is the intended behavior. Anyway if you leave it as internal you cannot put your production code to a different assembly unless you use InternalVisibleTo. — nemesv, Jun 13 '12 at 15:27
possible duplicate of [Verifying a method was called](http://stackoverflow.com/questions/1980108/verifying-a-method-was-called) — nemesv, Jun 13 '12 at 15:30
well, it really does work if I change `GetValue`to `public`. That's a real bummer. I've got a very complex class that uses a private method to write its result to an ascii-file. I only wanted to get rid of that file and check the string directly in my unit test. How am I supposed to do this? — Fabian, Jun 13 '12 at 15:52

score 8 · Accepted Answer · edited May 23 '17 at 12:08

8

OK, I found the answer to this in another question: How to Mock the Internal Method of a class?. So this is a duplicate and can be closed.

Nevertheless, here's the solution: just add this line to the Assembly.config of the project you want to test:

[assembly: InternalsVisibleTo("DynamicProxyGenAssembly2")] // namespace in Moq

edited May 23 '17 at 12:08

Community

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answered Jun 13 '12 at 16:11

Fabian

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To the test's Assembly.config? Or to the class being tested's Assembly.config? – Nick Apr 25 '14 at 21:09
Of the class that's being tested! I edited my answer and clarified that bit. – Fabian Jul 23 '14 at 11:26

score 0 · Answer 2 · answered Jun 13 '12 at 15:17

0

Did you try to specify Verifiable:

my.Setup(mock => mock.GetValue()).Callback(() => Console.WriteLine("MOCKED GetValue")).Returns(999).Verifiable();

answered Jun 13 '12 at 15:17

Felice Pollano

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didn't try it, but it makes no difference – Fabian Jun 13 '12 at 15:46

Partial mocking of class with Moq

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