The RSpec Book {Repost}

You'll get started right away with RSpec 2 and Cucumber by developing a simple game, using Cucumber to express high-level requirements in language your customer understands, and RSpec to express more granular requirements that focus on the behavior of individual objects in the system. You'll learn how to use test doubles (mocks and stubs) to control the environment and focus the RSpec examples on one object at a time, and how to customize RSpec to "speak" in the language of your domain.