Friday, 1 March 2013

System.Spec - Specifications By Example in C#


I am a big fan of TDD and when I first started doing it I was accustomed to using NUnit in C#. Then I started learning Ruby and fell in love in how they were doing TDD/BDD. The gem they use is called RSpec.

For a while I was jealous that we did not have something as cool in C#. There is NSpec, however for me if did not read that well.

So I decided to create System.Spec. We are currently using at the place I work at and we are really enjoying it. As we continue dogfooding this solution we will build more features into it.

An example specification looks like the following:

namespace YourCompany.Specs
    using NSubstitute;
    using System.Spec;

    public class ImportantSpecification : Specification
        protected override void Define()
            Describe("A very cool specification", () => {
                It("should do something that is good", () => {
                    var testInterface = Substitute.For<ITestInterface>();

As you can see there is some C# ceremonies that we need to take into consideration, Ruby allows for a much cleaner syntax. It follows closely the design of Jasmine.

Moving Forward

The following is what I plan doing in the coming weeks/months:

  1. Add a runner for ReSharper
  2. Add a runner for VS 2010
  3. Add a runner for Xamarin Studio (if possible)
  4. Allow reordering of tests.
I urge you to look at the solution and if you have any thoughts or enhancements just yell out.