In this chapter, we coerced you into following TDD principles when developing your application. We used Cucumber and Gherkin to write our end-to-end test, and used that to drive the implementation of our first endpoint. As part of our refactoring efforts, we've also migrated our API to use the Express framework.
At this point, you should have the TDD process drilled into your brain: Red. Green. Refactor. Begin by writing out test scenarios, implementing any undefined steps, then run the tests and see them fail, and finally, implementing the application code to make them pass. Once the tests have passed, refactor where appropriate. Rinse and repeat.
It's important to remember that TDD is not required to have self-testing code. You can, without following TDD, still write tests after to verify behavior and catch bugs. The emphasis of TDD is that it translates the design of your system into a set of concrete requirements, and uses these requirements to drive your development. Testing is...
