Question

My following straight forward test doesn’t pass (Though I feel it should). Either I am missing something or is not clear of Property.value constraint. please help me in understanding concept of property.value constraint.

public interface ISomeInterface
{
     void SomeMethod(string x, string y);
}

public class SomeClassTest
{

[Test]

public void SomeMethodTest()
    {

        MockRepository mocks = new MockRepository();
        ISomeInterface mockservice = mocks.StrictMock<ISomeInterface>();
        using (mocks.Record())
        {
            mockservice.SomeMethod("xValue", "yValue");
            LastCall.Constraints(Property.Value("x", "xValue"),
                                 Property.Value("y", "yValue"));
        }
        mockservice.SomeMethod("xValue", "yValue");
        mocks.Verify(mockservice);
    }
}

Exception raised:

Rhino.Mocks.Exceptions.ExpectationViolationException : ISomeInterface.SomeMethod(“xValue”, “yValue”); Expected #0, Actual #1.
ISomeInterface.SomeMethod(property ‘x’ equal to xValue, property ‘y’ equal to yValue); Expected #1, Actual #0.

Answer 1

This sample class illustrates the options for asserting methods were called with appropriate properties:

public class UsesThing
{
   private IMyThing _thing;

   public UsesThing(IMyThing thing)
   {
      _thing = thing;
   }

   public void DoTheThing(int myparm)
   {
      _thing.DoWork(myparm, Helper.GetParmString(myparm));
   }

   public void DoAnotherThing(int myparm)
   {
       AnotherThing thing2 = new AnotherThing();
       thing2.MyProperty = myparm + 2;
       _thing.DoMoreWork(thing2)
    }
}

Using simple values for assertions may work for methods like the DoTheThing method which uses value types:

[Test]
public void TestDoTheThing()
{
    IMyThing thing = MockRepository.GenerateMock<IMyThing>();
    UsesThing user = new UsesThing(thing);

    user.DoTheThing(1);

    thing.AssertWasCalled(t => t.DoWork(1, "one");
}

However, if you need to create an object in your method and pass it as a parameter like in the DoAnotherThing method, this approach will not work since you will not have a reference to the object. You have to check the property values of the unknown object, like this:

[Test]
public void TestDoAnotherThing()
{
    IMyThing thing = MockRepository.GenerateMock<IMyThing>();
    UsesThing user = new UsesThing(thing);

    user.DoAnotherThing(1);

    thing.AssertWasCalled(t => t.DoMoreWork(null), t => t.IgnoreArguments().Constraints(Property.Value("MyProperty", 3))));        
}

The new Rhino syntax would look like the following, but I am crashing VS 2008 when I use it:

thing.AssertWasCalled(t => t.DoMoreWork(Arg<AnotherThing>.Matches(Property.Value("MyProperty", 3))));