setup-pre-commit

Set Up Pre-Commit Hooks

What This Sets Up

• Husky pre-commit hook
• lint-staged Run Prettier on all staged files

  lint-staged running Prettier on all staged files

• Prettier configuration (if missing)

  Prettier config (if missing)

• The typecheck and test scripts in the pre-commit hook

  typecheck and test scripts in the pre-commit hook

Steps

1. Detect the package manager

Check package-lock.json（npm）、pnpm-lock.yaml（pnpm）、yarn.lock（yarn）、bun.lockb(bun). Use whichever exists. If unsure, default to npm.

Check for package-lock.json (npm), pnpm-lock.yaml (pnpm), yarn.lock (yarn), bun.lockb (bun). Use whichever is present. Default to npm if unclear.

2. Install dependencies

Install as devDependencies:

Install as devDependencies:

husky lint-staged prettier

3. Initialize Husky

npx husky init

This creates the .husky/ directory and adds prepare: "husky"。

This creates .husky/ dir and adds prepare: "husky" to package.json.

4. Create .husky/pre-commit

Write this file (Husky v9+ does not need a shebang):

Write this file (no shebang needed for Husky v9+):

npx lint-staged
npm run typecheck
npm run test

Adapt: Replace npm with the detected package manager. If the repository's package.json does not have typecheck or test scripts, omit the corresponding lines and inform the user.

Adapt: Replace npm with detected package manager. If repo has no typecheck or test script in package.json, omit those lines and tell the user.

5. Create .lintstagedrc

{
  "*": "prettier --ignore-unknown --write"
}

6. Create .prettierrc(if missing)

Only create if there is no Prettier configuration. Use the following defaults:

Only create if no Prettier config exists. Use these defaults:

{
  "useTabs": false,
  "tabWidth": 2,
  "printWidth": 80,
  "singleQuote": false,
  "trailingComma": "es5",
  "semi": true,
  "arrowParens": "always"
}

7. Verify

• .husky/pre-commit exists and is executable

  .husky/pre-commit exists and is executable

• .lintstagedrc exists

  .lintstagedrc exists

• The prepare script in package.json is "husky"

  prepare script in package.json is "husky"

• prettier configuration exists

  prettier config exists

• Run npx lint-staged to verify it works

  Run npx lint-staged to verify it works

8. Commit

Stage all changed/created files and commit with the message:Add pre-commit hooks (husky + lint-staged + prettier)

Stage all changed/created files and commit with message: Add pre-commit hooks (husky + lint-staged + prettier)

This will pass through the new pre-commit hooks — a smoke test to verify everything works.

This will run through the new pre-commit hooks — a good smoke test that everything works.

Notes

• Husky v9+ does not need a shebang added to hook files

  Husky v9+ doesn't need shebangs in hook files

• prettier --ignore-unknown Skip files that Prettier cannot parse (such as images)

  prettier --ignore-unknown skips files Prettier can't parse (images, etc.)

• pre-commit first runs lint-staged (fast, staged files only), then runs the full type check and tests

  The pre-commit runs lint-staged first (fast, staged-only), then full typecheck and tests