Why must I watch a test fail before writing the code?

Watching a test fail proves that the test actually checks the intended behavior and isn't passing by accident. If you don't see it fail, you don't know if it's testing the right thing.

What if my test passes immediately?

If a test passes immediately, you are testing existing behavior or your test is flawed. You must fix the test until it fails correctly for the missing feature before proceeding to the 'Green' phase.

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

The Iron Law states that no production code should be written without a failing test first. If code is written before the test, it must be deleted and the process restarted from the test.

How does this skill handle bug fixes?

It requires writing a failing test that reproduces the bug exactly before any fix is implemented. This ensures the fix is effective and prevents the bug from ever returning.

When is it acceptable to skip TDD?

TDD should always be used for features, bugs, and refactoring. Exceptions are only made for throwaway prototypes, generated code, or configuration files after consulting with a human partner.

Test-Driven Development (TDD)

Name: Test-Driven Development (TDD)
Author: pur3v4d3r

bypur3v4d3r

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보안 및 테스팅

Enforces strict Red-Green-Refactor cycles to ensure all production code is preceded by failing tests.

This skill transforms Claude into a disciplined TDD practitioner, ensuring high code quality by mandating that failing tests be written before any implementation code. It provides a structured framework for the Red-Green-Refactor cycle, helps identify edge cases early, and prevents common rationalizations for skipping tests, resulting in more robust, maintainable, and self-documenting codebases. By strictly following the 'Iron Law'—no production code without a failing test—this skill eliminates technical debt at the source and provides a systematic approach to both feature development and bug fixing.

주요 기능

011 GitHub stars

02Comprehensive bug-fix protocol requiring reproduction through failing tests

03Minimal code implementation focus to prevent over-engineering and YAGNI violations

04Structured Red-Green-Refactor workflow with mandatory verification checkpoints

05Identification and prevention of common TDD rationalizations and anti-patterns

06Strict enforcement of the Iron Law: No production code without a failing test first

사용 사례

01Safely refactoring existing codebases by establishing a 'Green' baseline before modification

02Fixing complex bugs by first isolating and reproducing them via automated tests

03Developing new features with high confidence and minimal regression risk

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add pur3v4d3r/pur3-pkb-codebase test-driven-development

For use in Claude.ai and ChatGPT

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