tdd-workflow

The red-green-refactor cycle in test-driven development structures feature work by first writing a failing test (RED), implementing minimal code to pass it (GREEN), and then improving the design without changing behavior (REFACTOR). This ensures repeatable, high-quality outcomes and reduces defects.

To structure unit tests for readability and maintainability, apply the AAA testing pattern. The AAA pattern organizes tests into three distinct phases: Arrange the preconditions, Act on the system under test, and Assert the expected outcomes.

To start writing tests before code in a feature development cycle, follow the test-driven development workflow: write a failing unit test first, implement the minimal code required to make that test pass, and then refactor the implementation while maintaining test confidence.

Yes, test-driven development works for software teams without an existing test suite. The workflow applies directly to new feature development cycles by establishing a rhythm of writing unit tests first, ensuring repeatable high-quality outcomes from the start.

Refactoring may break existing unit tests if the internal design changes without updating test expectations. To maintain confidence during refactors, follow clear rules for writing effective tests and ensure the test suite covers the expected behavior through the AAA pattern.