tdd-failing-tests-loop

What problem does it solve?

This guide provides a repeatable red-green-refactor loop to safely overhaul, refactor, or harden a code path using strict failing-tests-first TDD; it ensures contracts, tests, and implementation stay aligned while mitigating risk.

Core Features & Use Cases

• Map the existing contract before touching code to capture durable behavior boundaries.
• Write purposeful red tests that express explicit contract gaps.
• Run the smallest relevant test slice to verify the targeted surface.
• Make the smallest green change that satisfies the new contract.
• Refactor after the contract is green to simplify and consolidate.
• Sync internal docs, prompts, and policy to reflect the new runtime contract.
• Broaden verification to adjacent subsystems and related suites.
• Report the red → green timeline for auditable change.

Quick Start

Apply the red-green-refactor loop to a subsystem by mapping the contract, writing red tests for gaps, executing the smallest green change, and recording the red→green timeline.