Unit Testing Principles, Practices, and Patterns

Chapter 11. Unit testing anti-patterns

This chapter covers

• Unit testing private methods
• Exposing private state to enable unit testing
• Leaking domain knowledge to tests
• Mocking concrete classes

This chapter is an aggregation of lesser related topics (mostly anti-patterns) that didn’t fit in earlier in the book and are better served on their own. An anti-pattern is a common solution to a recurring problem that looks appropriate on the surface but leads to problems further down the road.

You will learn how to work with time in tests, how to identify and avoid such anti-patterns as unit testing of private methods, code pollution, mocking concrete classes, and more. Most of these topics follow from the first principles described in part 2. Still, ...