Test-Driven Development Skill

The Test-Driven Development (TDD) skill is a coding practice that emphasizes writing tests before writing the actual code. It is used to ensure that code works as expected and to catch bugs early in the development process. This skill is particularly useful when implementing new logic, fixing bugs, or modifying existing functionality. The TDD cycle involves writing a failing test (RED), writing minimal code to pass the test (GREEN), and then refactoring the code (REFACTOR). The skill also covers the Prove-It Pattern for bug fixes, which involves writing a test to reproduce the bug before attempting a fix. The Test Pyramid model is used to structure tests, with a focus on small, fast unit tests and fewer, larger end-to-end tests. Good testing practices, such as testing state over interactions and preferring real implementations over mocks, are also emphasized.