Rhino Mocks AAA Quick Start?

Question

I\'ve been looking around for some decent information on using Rhino Mocks 3.5+ with the AAA syntax. I find a lot of blogs that have a mix of things from the old and new whi

Answer 1

First make sure you know what you mean for each A in AAA. You may know but I'll include my working definitions for completeness of the answer:

• Arrange is where I set up inputs, mocks/stubs, the object with the method under test
• Act is where I call the method under test
• Assert is where I verify things occurred or didn't according to expectation

I like to put comments in my test code to remind me to think about each of those things. An example may help clarify: Suppose I have a service layer class which uses two provider layer classes, one from an "old" system and one from a "new" system; I am testing that the method which copies old things to the new system calls the "CreateThing" method one time for each old thing found.

[Test]
public void Should_create_new_Thing_for_each_old_Thing()
{
  // -----
  // arrange

  // hardcode results from old system provider
  List<Thing> oldThings = new List<Thing> { ... };

  // old system provider
  var oldProvider = MockRepository.GenerateStub<IOldSystemProvider>();
  oldProvider.Stub(m=>m.GetThings()).Return(oldThings);

  // new system provider
  var newProvider = MockRepository.GenerateStub<INewSystemProvider>();

  // service object
  var svc = new MyService(oldProvider, newProvider);

  //-----------
  // act
  var result = svc.CopyThings();

  //------------
  // assert
  oldThings.ForEach(thing => 
                    newProvider.AssertWasCalled(prov => prov.CreateThing(thing)));
}

Answer 2

I assume that you're familiar with official documentation, which is quite good in my opinion. My suggestion is to try to use Rhino, and when you encounter some more specific problem search for solution wither on SO or somewhere else. I don't think that there is a comprehensive cheat sheet for Rhino mocks. I guess you'll have more luck asking "How can I do this and that using Rhino Mocks"

Edit: Well, you don't need to use Record/Playback when targeting AAA. There are three steps involved in AAA:

• Arrange, which stands for setting up the behavior of mocked class, for example

.

IOmicronDll mockWrapper = MockRepository.GenerateMock<IOmicronDll>();
mockWrapper.Expect(wrapper => wrapper.Lock(1, ref errors)).OutRef(string.Empty).Return(true).Repeat.Any();
mockWrapper.Expect(wrapper => wrapper.Exec(1, "sys:cfg?(type)", ref output, ref errors)).OutRef("1,CMC 56,0;", "").Return(true).Repeat.Any();
mockWrapper.Expect(wrapper => wrapper.Exec("1", "sys:cfg?(type)", ref output, ref errors)).OutRef("1,CMC 56,0;", "").Return(true).Repeat.Any();
Microsoft.Practices.Unity.UnityContainer c = new Microsoft.Practices.Unity.UnityContainer();
c.RegisterInstance<IOmicronDll>(mockWrapper);

• Act, which stands for executing the tests

  public Omicron(int deviceID)
  {
      try
      {
          if (g_Omicron == null)
              g_Omicron = Microsoft.Practices.ServiceLocation.ServiceLocator.Current.GetInstance<CMEngineWrapper.IOmicronDll>();
          m_UniqueIdentifier = Guid.NewGuid();
          m_Logger = Microsoft.Practices.ServiceLocation.ServiceLocator.Current.GetInstance<AdvAdmittance.Framework.ILogger>();
          m_ID = deviceID;
          GetConfiguration();
          g_InstancesCount++;
          m_PollThread = new Thread(new ThreadStart(DoPoll));
          m_PollThread.Start();
      }
  

• And Assert, which stands for veryfing the results

.

Assert.AreEqual("CMC 56", omicron.Type);
mockWrapper.AssertWasCalled(wrapper => wrapper.Release(), options => options.Repeat.AtLeastOnce());

Perhaps the above examples aren't the best, but might get you into right direction.

Answer 3

I have written a Rhino Mocks Arrange / Act / Assert (AAA) Syntax Quick Reference. It contains condensed information about this syntax style collected from Ayende's web site and several other blogs.

Answer 4

You'd probably want to start at Ayende's original post on AAA, and than take a look at Ben Hall's nice blog post about AAA. Than you could use all the complete references mentioned in other answers...