The previous chapters present a simple unit test framework and the fundamentals of xUnit. The unit test framework's architecture is important to understand, but not something you have to think about often. Most of your time should be spent writing unit tests, implementing production code to make the tests pass, or refactoring. This chapter includes examples of common patterns used when writing unit tests, as well as related tips on unit test development.
The code examples in this chapter are unit tests of additional virtual library functionality, including looking up books by author and title, looking up multiple books by one author, and removing books from the library. The Library and Book code to implement the new features is given at the end of the chapter.