.Equals() method on the mocks. It just makes for more readable code to be able to ask a collection whether it .Contains() the mock than writing out the iteration myself.But it does bloat my test-cases somewhat. Here's an example setting up a mock of a class with the equality set that returns
true if it's compared to itself:[Test(Description = "Mock of equals on an instance succeeds")]
public void MockingEquals_SameInstance_AreEqual() {
var mocker = new Mock<SomeClass>();
mocker.Setup(x => x.Equals(mocker.Object)).Returns(true);
var mockedObject = mocker.Object;
Assert.That(mockedObject.Equals(mockedObject));
}
That's fine if it's only in one test, but I don't like to repeat that all over my code. My first thought was to make a convenience method which set up the equality for me:
public static Mock<T> ReferenceEquals<T>(Mock<T> mock) where T : class {
mock.Setup(m => m.Equals(mock.Object)).Returns(true);
return mock;
}
Sticking this in some public place now allows me to set up my test from before like this:
[Test(Description = "Mock of equals on an instance succeeds")]
public void MockingEquals_SameInstance_AreEqual() {
var mocker = new Mock<SomeClass>();
ReferenceEquals(mocker);
var mockedObject = mocker.Object;
Assert.That(mockedObject.Equals(mockedObject));
}
That's certainly better. But, we can do better than that, can't we? Let's make it an extension-method, for great success! To use this code the class containing the extension-method must be static.
public static void HasReferenceEquality<T>(this Mock<T> mock) where T : class {
mock.Setup(m => m.Equals(mock.Object)).Returns(true);
}
And with that our test has been transferred to the (in my opinion) much more readable:
[Test(Description = "Mock of equals on an instance succeeds")]
public void MockingEquals_SameInstance_AreEqual() {
var mocker = new Mock<SomeClass>();
mocker.HasReferenceEquality();
var mockedObject = mocker.Object;
Assert.That(mockedObject.Equals(mockedObject));
}
Great success!
