There is no bug in Rhino mocks if that’s what you’re thinking. Rhino mocks 3.5 just uses things that VB.Net 9.0 can’t use and that can be frustrating. I wonder what possessed them to do it like that?

So let me tell the story.

I got a service and a repository, the service calls the repo.

Repo interface:

The repo implementation:

The service interface:

The service implementation:

And now we want to test it.

First, we test the service’s findall method. We mock out the repo and see if the repo was called.

This works just fine.

Now I want to see if the update method is also used as it should be, so I write this:

But that gives me an error “Expression does not produce a value.". Mmmm, you can find an explanation for that here. And the solutions is there as well. The solution is, however, a bit clunky, as he says.

So in the end you could do this:

Which solve the problem, more or less.

So, last week Ayende made a new version of Rhino Mocks available, namely version 3.5. He made a post on what is new and shiny, but I would like to look at what the new AAA syntax has in store for us VB.Net users.

And I want to tell you how it used to look and how it looks now.

This is the old version, works with Rhino mocks 3.4.

Ok, so we notice the use of _mocker and DynamicMock to create our Mock objects and then we set our expectations, then we do a replayall and execute the methods under test. When the test is done the verifyall is executed which looks if our expectations are met.

Now we switch to Rhino mocks 3.5 and see that we get an error on Expect saying that the signature is not correct. No worry this is because it is choosing the wrong Expect. It is namely trying to use the extension method there. Just add Rhino.Mocks. before the Expect and all is well again. Look how the imports doesn’t do the same thing.

And now on to the new.

Look at how the _mocker.DynamicMock are replaced by MockRepository.GenerateMock and how the _mocker object has disappeared all together. The Expect.Call’s have been replaced with Object.Stub methods. And the ReplayAll and VerifyAll are now gone. Overall, a bit simpler and more meaningful.

Here is another good article about the use of AAA and Rhino mocks but then in C#.

And it only goes to show that even the smartest and best people don’t get it right the first time .

Ayende asked to add this to his wiki and so I did http://ayende.com/wiki/Rhino+mocks+3.5+and+VB.Net+the+AAA+syntax.ashx

Let’s say we want to test to see if our object really throws that event when we need it to.

So when calling a method SomeSub an event throwme will be raised.

Now we make a little unittest class that looks like this.

Just a few notes. I created an interface just for this test. And interface with a method with the same signature as the event. Then in the Test, I subscribe the event to that method. I didn’t forget to set IgnoreArguments and I called the Method on our object.

If the test goes green, we know that the event is raised when we call the sub. Now it’s just a matter of subscribing to that event.