tdd-workflow

Test-first development enforces writing failure and success tests before implementing minimal route logic. You write unit, integration, and end-to-end tests first, implement the smallest code change to pass them, then refactor once the suite is green.

Coverage discipline during refactoring requires verifying at least 80% coverage and testing edge cases, error paths, and boundary conditions. You validate existing tests remain green and confirm coverage thresholds before modifying code to prevent regressions.

Playwright E2E workflows apply to user journey testing within a test-first approach. You write end-to-end tests alongside unit and integration tests to validate components, APIs, and user journeys before implementing the underlying logic.

Test-first development works for bug fixes and new feature implementation by forcing a workflow that catches regressions early. You start by writing tests that reproduce the bug or define the feature, implement the fix or change, and verify coverage.

Validating edge cases and error paths before refactoring keeps changes safe and catches regressions early. Fast feedback loops confirm boundary conditions are tested, ensuring refactoring does not introduce unexpected behavior into existing logic.