Fluent Rhino Mocks

I was recently introduced to the fluent interface that the Rhino Mocks library exposes. I wasn’t sure that it was as easy to read as the Record/Playback syntax I was use to using. I persisted with the ‘new’ syntax to see if I could see any benefit of using the fluent interface.

I now find that using the fluent interface helps on a number of fronts.

• Eliminates many potential mistakes buy using method chaining.
• Helps me keep to one Expectation or Assert per test.
• Makes my code more like an English sentence and therefore easier to read.
• Means that my code is smaller.
• Allows me to use ExpectingInSameOrder – although I haven’t found a really good use for this yet.

I have to say I wasn’t instantly sold on the syntax but the more I used it the more I like it.

Here is a simple example of a refactored test using the fluent interface.

Original

[Test]
public void Should_leverage_the_repository_to_retrieve_all_games()
{
    using (mockery.Record())
    {
        Expect.Call(repository.Find(null)).Return(new List<Game>()).IgnoreArguments();
    }

    using (mockery.Playback())
    {
        service.GetGames();
    }
}

New

[Test]
public void Should_leverage_the_repository_to_retrieve_all_games()
{
    With.Mocks(mockery)
        .Expecting(() => Expect.Call(repository.Find(null)).Return(new List<Game>()).IgnoreArguments())
        .Verify(() => service.GetGames());
}

A whole 50% smaller!

~ by Tim on 30 October 2008.