Refactoring

Remember that the TDD process can be summed up with the phrase "Red. Green. Refactor". Here, we've written failing tests (red) and we've written some code to make them pass (green); therefore, the next step is to refactor, which, as a reminder, means restructuring and improving the quality of our implementation without changing its external behavior. This can mean the following:

• Reducing duplicated code (keeping things DRY)
• Improving readability
• Making our code more modular
• Reducing cyclomatic complexity, probably by breaking larger functions into smaller ones

Refactoring should be done for our entire code base, which includes both the test code and our application code. Here, however, our application code is already quite neat and there are no obvious areas we can improve on at this time. Therefore, we can focus on improving our test code.