Does this skill support mocking?

Yes, though it encourages using real code whenever possible. It provides guidance on avoiding testing anti-patterns, such as testing mock behavior instead of real system logic.

Can I use this skill for existing legacy code?

Absolutely. When modifying existing code or fixing bugs in legacy systems, this skill helps you write failing tests for the new behavior or bug reproduction before making any changes.

Why is watching a test fail mandatory?

Watching a test fail (the Red phase) proves that the test is actually checking the intended behavior and that the failure is caused by the missing feature rather than a configuration error or typo.

What is the 'Iron Law' of this TDD skill?

The Iron Law dictates that no production code should be written without a failing test first. If code is written before a test, the skill mandates deleting it and starting over to ensure the test accurately drives the implementation.

Test-Driven Development (TDD)

Name: Test-Driven Development (TDD)
Author: tianyuanztm

bytianyuanztm

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보안 및 테스팅

Enforces a rigorous Red-Green-Refactor workflow to ensure high-quality, verified production code through test-first implementation.

This skill transforms Claude into a disciplined TDD practitioner, strictly adhering to the 'Iron Law' that no production code is written without a preceding failing test. It guides the development process through the mandatory cycles of writing minimal tests, verifying failures, implementing the simplest possible solutions, and refactoring while maintaining green status. By preventing common shortcuts like 'testing after' or manual-only verification, this skill ensures that every line of code is purposeful, documented by tests, and free from regression risks.

주요 기능

01Guidance on writing minimal, behavior-focused test cases

020 GitHub stars

03Prevention of implementation bias by requiring test-first logic

04Strict enforcement of the Red-Green-Refactor development cycle

05Automated verification of test failures to ensure test validity

06Built-in checks to identify and stop common TDD rationalizations

사용 사례

01Reproducing and fixing bugs by establishing failing test cases first

02Safely refactoring complex logic with a continuous safety net

03Building new features with guaranteed behavioral coverage

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add tianyuanztm/myplan test-driven-development

For use in Claude.ai and ChatGPT

Download Skill