pre-commit-checks

name	pre-commit-checks
description	Run and troubleshoot the pre-commit hook quality checks. Use when commits fail, when adding new checks, or when verifying code quality locally.
metadata	{"version":"2.0"}

Pre-Commit Quality Checks

The pre-commit hook uses lint-staged for performance, running checks only on staged files. All must pass for a commit to proceed.

Checks

1. Formatting and Linting (lint-staged)

./node_modules/.bin/lint-staged

Configuration in package.json under "lint-staged":

• JS/TS files: prettier --write → eslint --fix
• Other files: prettier --write

Runs only on staged files for maximum performance.

2. Type Checking (TypeScript)

npx tsc --noEmit

Runs on the full project (fast enough, ensures project-wide type safety). No auto-fix — type errors must be resolved manually.

3. Unit Tests (Vitest)

./node_modules/.bin/vitest related --run $(git diff --name-only --cached)

Runs tests only for files related to staged changes using Vitest's "related" mode.

Guarantee

If pre-commit passes locally, CI must be green. If this guarantee is ever broken, it is a bug in the pipeline and must be fixed immediately.

Key Benefits

• Performance: Only processes staged files for formatting/linting
• Stability: Uses local paths (./node_modules/.bin/) instead of npx to avoid $PATH issues
• Smart testing: Vitest "related" mode runs only tests affected by your changes
• Auto-fix: Prettier and ESLint automatically fix issues when possible

Troubleshooting

• lint-staged fails: Check the output for specific Prettier or ESLint errors. Most issues are auto-fixed; remaining issues need manual correction.
• TypeScript fails: Read the type error carefully. Do not use // @ts-ignore or any to suppress.
• Tests fail: Run npx vitest interactively to debug. The hook only tests files related to your changes.
• Hook not running: Ensure .husky/pre-commit is executable: chmod +x .husky/pre-commit
• lint-staged not found: Run npm install to install dependencies.

Manual Check Commands

To run checks manually before committing:

# Format all files
npm run format

# Lint all files
npm run lint

# Type check
npm run typecheck

# Run full test suite
npm test