Test Runner Skill

Smart test execution automatically detects changed files in your git repository and runs only related tests, reducing execution time by 85-92% compared to full suite runs. This mode is ideal for active development when you need instant feedback on your recent changes.

Five modes optimize different workflows: Smart Mode runs tests for changed files, Full Mode validates the entire suite, Coverage Mode reports code coverage metrics, Watch Mode enables continuous testing during development, and Failed Only re-runs only previously failed tests.

Yes, the Skill requires a conventional file-to-test mapping, such as src/services/X.ts mapping to src/services/__tests__/X.test.ts. Your project must have a configured test runner and use git for change detection to work properly.

You need a git-based JavaScript or TypeScript project with an npm environment, Node.js installed, and a configured test runner. The Skill detects changed files through git and executes tests using your existing test suite tooling.

Use Full Mode before commits or pull requests to validate the entire test suite, ensuring no regressions in untouched code. Smart Mode is best for active development iteration when you need rapid feedback on specific changes.

Yes, Coverage Mode runs tests and produces detailed code coverage reports, making it ideal before releases. This helps ensure code quality standards are met across your modified and related test files.