Question

Extension methods are not good for testing (that’s described here: Mocking Extension Methods with Moq, http://www.clariusconsulting.net/blogs/kzu/archive/2009/12/22/Howtomockextensionmethods.aspx).

But probably there are some solutions for mocking of Unity methods? In my case I have the following function:

public class MyManager
{
    public MyManager(IUnityContainer container) : base(container) { }

    public IResult DoJob(IData data)
    {
        IMyLog log = MyContainer.Resolve<IMyLog>();

        ... use log.Id ...

        MyContainer.Resolve<...>();//usage for other purposes...
    }

I want to be sure that ‘DoJob’ method will always get ‘IMyLog’ object from container, but not from other sources… how could I test that?

My original idea was to change ‘DoJob’ method implementation and use:

IMyLog log = UnityContainer.Resolve(typeof(IMyLog)) as IMyLog;

But ‘Resolve(Type t, …)’ is also an extension method…

Any thoughts are welcome.

P.S. Please note, that ‘my log’ object is created far-away from MyManager.DoJob…

Answer 1

Guess, I found most appropriate solution for test: It is not necessary to mock unity container and check if ‘log’ object was taken from it. I will just make a mock for ‘Log’ object, register its object instance in the container and check in test if this log object is really used.

This will do what is required.

        Mock<IMyLog> mockLog = new Mock<IMyLog>();
        mockLog.Setup(mock=>mock.Id).Returns(TestLogId);

        IUnityContainer container = new UnityContainer();
        container
            .RegisterInstance(mockCommandExecutionLog.Object)
            ...
            ;

        ...

        mockLog.Verify(
            mock => mock.Id,
            Times.Once(),
            "It seems like 'Log' object is not used"
            );

Thanks.