Mocking a non-virtual instance method across instances

[Asim Imam]

Hi!

Please consider the case when the method I want to test looks like this:

public class Foo {
    public void TestMe(<arg list>)
    {
        [business logic omitted...]

         Helper hlp = new Helper();
         bool wasHelped = hlp.HelpMe(<arg list>);   

        [business logic omitted...]
    }
}

Since the object "hlp" is initialized within the method that's to be tested, as opposed to being instantiated by the test method, will JustMock allow mocking the (non-virtual, non-static) method "Helper.HelpMe" such that the above call to "HelpMe" is re-routed to the mocked implementation? If so, what would be the syntax for doing this?

[Ricky]

Hi Asim,

Thanks again for reaching us.

Yes you can mock the above scenario with JustMock. I am attaching a project that mocks the HelpMe method to return a certain value instead executing it that on the other hand throws exception. Please note that this is a commercial feature and not available in the free edition.

Kind Regards,
Mehfuz
the Telerik team

[Matt Kalai]

Test method does not use created mock.  The dependency is not removed. I believe that you mist injecting mock up into the class under the test. 

[Ricky]

Hi Matt,

Thanks again for the suggestion. However, in JustMock we have a feature called partial mocking and it is also possible to ignore instance for a specific setup.

Therefore, I can easily do :

var helper = new Helper();

Mock.Arrange(() => helper.HelpMe(Arg.AnyInt)).Returns(true).IgnoreInstance();

new Foo().TestMe(10)

Here the TestMe method looks like:

public void TestMe(int arg1)
{
    Helper hlp = new Helper();
    bool wasHelped = hlp.HelpMe(arg1);
}

Therefore, you can easily mock a method without ever passing the dependency.

Kind regards,
Mehfuz
the Telerik team