In this chapter, you learned quite a lot about TDD, and the following is the summary of the key takeaway points:

• TDD is an Extreme Programming (XP) practice
• TDD is a bottom-up approach that encourages us to start with a test case, hence it is commonly referred to as LowercaseTest-First Development
• You learned how to write test cases using Google Test and Google Mock Frameworks in Linux and Windows
• You also learned how to write an application that follows TDD in Linux and Visual Studio on the Windows platform
• You learned about the Dependency Inversion technique and how to unit test a code by isolating its dependency using the Google Mock Framework
• The Google Test Framework supports Unit Testing, Integration Testing, Regression Testing, Performance Testing, Functional Testing, and so on
• TDD mainly insists on Unit Testing, Integration Testing, and Interaction Testing while complex functional testing must be done with Behavior-Driven Development
• You learned how to refactor code smells into clean code while the unit test cases that you wrote give continuous feedback

You have learned TDD and how to automate Unit Test Cases, Integration Test Cases, and Interaction Test cases in a bottom-up approach. With BDD, you will learn the top-down development approach, writing end-to-end functionalities and test cases and other complex test scenarios that we did not cover while discussing TDD.

In the next chapter, you will learn about Behavior-Driven Development.