Mutation Testing

소개

This skill empowers Claude to go beyond simple code coverage by performing mutation testing using Stryker for TypeScript/JavaScript and mutmut for Python. It works by injecting small, intentional faults into your source code—if your tests still pass, they are marked as 'survived,' indicating a gap in your test logic. This is an essential tool for developers building high-reliability systems who need to ensure their test suites actually catch bugs rather than just executing lines of code.

주요 기능

• Guidance on fixing common test smells and boundary condition gaps
• Automated mutation analysis for TypeScript/JS (Stryker) and Python (mutmut)
• 21 GitHub stars
• Support for incremental testing to focus only on changed files
• Detailed HTML report generation and interpretation
• Identification of 'survived' mutants to pinpoint weak assertions

사용 사례

• Setting quality gates in CI/CD pipelines based on mutation scores
• Improving reliability for mission-critical business logic and edge cases
• Auditing existing test suites to find tests that pass even when logic is broken