test-driven-development

Test-driven development improves software quality by enforcing a workflow where you write a failing test before implementation, which reduces debugging time and catches regressions early in the development cycle.

To apply red-green-refactor, you first write a failing test defining the desired behavior, implement the minimal code required to pass that test, and then refactor the codebase for clarity without breaking functionality.

The core rule of test-driven development is the iron law that no production code is written without first starting from a failing test, ensuring every feature has guaranteed test coverage and safer changes.

Yes, test-driven development is highly effective for safe refactoring because it provides automated feedback through existing tests, ensuring that structural changes do not alter or break current software behavior.

You should not rely on test-driven development when writing exploratory code or throwaway scripts, as the strict requirement to create failing tests before implementation adds unnecessary overhead to non-production code.

The best way to keep tests focused during test-driven development is to write tests that target single behaviors and adhere to the red-green-refactor workflow, maximizing reliability and preventing test bloat.