Can I write the production code first and the test later?

No. The core principle of this skill is that production code must only be written after a test has been observed to fail. Writing tests after implementation is biased and proves less about the code's correctness.

Is TDD slower than traditional coding?

While it may feel slower initially, TDD significantly reduces time spent on debugging and prevents regressions. This leads to a faster and more stable development lifecycle overall.

How does this skill handle bug fixes?

For bugs, the skill mandates writing a failing test that reproduces the specific issue before any fix is implemented. This confirms the bug exists and proves the fix works once the test turns green.

What should I do if my test passes immediately?

If a test passes immediately, you are testing existing behavior or the test is written incorrectly. You must modify the test to ensure it fails because the feature is missing, not due to a typo or syntax error.

Test-Driven Development (TDD)

Name: Test-Driven Development (TDD)
Author: lastdays03

bylastdays03

0•

セキュリティとテスト

Enforces a strict Red-Green-Refactor workflow to ensure high-quality, verified code implementation for features and bug fixes.

This skill provides Claude with a rigorous framework for Test-Driven Development, preventing the creation of production code without a prior failing test. It guides users through the core TDD cycle—writing a minimal failing test, implementing just enough code to pass, and refactoring for clarity—while strictly forbidding 'test-after' workflows. By standardizing the Red-Green-Refactor process, it helps maintain high test coverage, reduces technical debt, and ensures that every piece of logic is systematically verified from the moment of inception.

主な機能

01Integrates debugging workflows to reproduce bugs with failing tests first

02Provides standardized verification checklists for new features and bug fixes

03Guides developers through the complete Red-Green-Refactor development cycle

04Enforces the 'Iron Law' of no production code without a failing test first

050 GitHub stars

06Identifies and corrects common TDD rationalizations and anti-patterns

ユースケース

01Safely refactoring existing logic while maintaining functional parity

02Reproducing and fixing software bugs through test-first methodologies

03Implementing new features with high confidence and systematic verification

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add lastdays03/flask_template test-driven-development

For use in Claude.ai and ChatGPT

Download Skill