Summary
This is a long chapter, I admit, but my defense is that it has plenty of examples to cover many real-life DI scenarios. Also, DI automatically encourages good software engineering practices, so we had to include the relevant practices. If you were to develop TDD-style, you would spend around 10% of your coding time doing DI-related tasks, and I hope this chapter did the right job and added to your knowledge.
DI is mainly used with unit tests, so without it, DI may feel less interesting. The next chapter, Getting Started with Unit Testing, will use the WFA application that we refactored here, and hopefully, you will appreciate further this design pattern.
