Git Hooks Manager

---
name: git-hooks-manager
description: Setup and manage git hooks for pre-commit, pre-push automation (lint, test, format)
allowed-tools: ["Write", "Read", "Bash"]
version: 1.0.0
author: GLINCKER Team
license: Apache-2.0
keywords: [git, hooks, pre-commit, automation, quality]
---

# Git Hooks Manager

Setup automated git hooks for pre-commit and pre-push workflows. Enforce code quality, run tests, format code, and prevent bad commits from reaching your repository.

## What This Skill Does

- Creates pre-commit hooks (lint, format, test)
- Sets up pre-push hooks (full test suite)
- Installs commit-msg hooks (enforce conventions)
- Configures husky or manual hooks
- Prevents commits with failing checks
- Auto-formats code before commit

## Instructions

### Phase 1: Detect Project Type

```bash
Use Read to check:
- package.json → Node.js (use husky)
- pyproject.toml → Python (use pre-commit)
- .git/hooks → Manual hooks
```

### Phase 2: Node.js Setup (Husky)

**Install husky**:

```bash
npm install --save-dev husky lint-staged
npx husky init
```

**Configure package.json**:

```json
{
  "scripts": {
    "prepare": "husky"
  },
  "lint-staged": {
    "*.{js,jsx,ts,tsx}": [
      "eslint --fix",
      "prettier --write"
    ],
    "*.{json,md,yml}": [
      "prettier --write"
    ]
  }
}
```

**Pre-commit hook (.husky/pre-commit)**:

```bash
#!/bin/sh
. "$(dirname "$0")/_/husky.sh"

echo "🔍 Running pre-commit checks..."

# Run linter
npm run lint || exit 1

# Format code
npx lint-staged || exit 1

# Run tests on staged files
npm test -- --findRelatedTests $(git diff --cached --name-only --diff-filter=ACM | grep -E '\.(js|jsx|ts|tsx)$' | tr '\n' ' ') || exit 1

echo "✅ Pre-commit checks passed!"
```

**Pre-push hook (.husky/pre-push)**:

```bash
#!/bin/sh
. "$(dirname "$0")/_/husky.sh"

echo "🔍 Running pre-push checks..."

# Run full test suite
npm test || exit 1

# Check types (if TypeScript)
npm run type-check || exit 1

# Build check
npm run build || exit 1

echo "✅ Pre-push checks passed!"
```

**Commit-msg hook (.husky/commit-msg)**:

```bash
#!/bin/sh
. "$(dirname "$0")/_/husky.sh"

# Enforce conventional commits
npx --no -- commitlint --edit $1 || exit 1
```

### Phase 3: Python Setup (pre-commit)

**.pre-commit-config.yaml**:

```yaml
repos:
  - repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v4.5.0
    hooks:
      - id: trailing-whitespace
      - id: end-of-file-fixer
      - id: check-yaml
      - id: check-added-large-files
      - id: check-json
      - id: check-merge-conflict
      - id: detect-private-key

  - repo: https://github.com/psf/black
    rev: 23.12.1
    hooks:
      - id: black
        language_version: python3.11

  - repo: https://github.com/pycqa/flake8
    rev: 7.0.0
    hooks:
      - id: flake8
        args: ['--max-line-length=88', '--extend-ignore=E203']

  - repo: https://github.com/pycqa/isort
    rev: 5.13.2
    hooks:
      - id: isort
        args: ['--profile', 'black']

  - repo: https://github.com/pre-commit/mirrors-mypy
    rev: v1.8.0
    hooks:
      - id: mypy
        additional_dependencies: [types-all]

  - repo: local
    hooks:
      - id: pytest
        name: pytest
        entry: pytest
        language: system
        pass_filenames: false
        always_run: true
```

**Install**:

```bash
pip install pre-commit
pre-commit install
pre-commit install --hook-type commit-msg
```

### Phase 4: Manual Hooks

For projects without package managers:

**.git/hooks/pre-commit**:

```bash
#!/bin/sh

echo "🔍 Running pre-commit checks..."

# Check for TODOs
if git diff --cached | grep -i "TODO"; then
    echo "❌ Found TODO comments. Please remove or track them properly."
    exit 1
fi

# Check for console.log
if git diff --cached --name-only | grep -E '\.(js|jsx|ts|tsx)$' | xargs grep -n "console\.log"; then
    echo "❌ Found console.log statements. Please remove them."
    exit 1
fi

# Check for hardcoded secrets
if git diff --cached | grep -E '(password|secret|api_key|apikey)\s*=\s*["\'][^"\']+["\']'; then
    echo "❌ Possible hardcoded secret detected!"
    exit 1
fi

# Check file size
for file in $(git diff --cached --name-only); do
    if [ -f "$file" ]; then
        size=$(wc -c < "$file")
        if [ $size -gt 1048576 ]; then # 1MB
            echo "❌ File $file is too large (>1MB)"
            exit 1
        fi
    fi
done

echo "✅ Pre-commit checks passed!"
```

## Hook Types

### pre-commit
- Linting (ESLint, Flake8, Pylint)
- Formatting (Prettier, Black, rustfmt)
- Type checking (TypeScript, mypy)
- Unit tests on changed files
- Secret detection

### pre-push
- Full test suite
- Build verification
- Coverage check
- Integration tests

### commit-msg
- Conventional Commits enforcement
- Ticket number requirement
- Message length validation

### post-commit
- Notifications
- Log generation
- Cleanup tasks

## Advanced Features

### Skip Hooks (When Needed)

```bash
# Skip pre-commit
git commit -n -m "Emergency fix"

# Skip pre-push
git push --no-verify
```

### Selective Hooks

```yaml
# Only run on specific branches
if [ "$(git branch --show-current)" = "main" ]; then
    echo "Running extra checks on main branch..."
fi
```

### Performance Optimization

```bash
# Cache linter results
if [ ! -f .lint-cache ] || [ "$(git diff --cached | md5sum)" != "$(cat .lint-cache)" ]; then
    npm run lint
    git diff --cached | md5sum > .lint-cache
fi
```

## Tool Requirements

- **Write**: Create hook files
- **Read**: Detect project configuration
- **Bash**: Make hooks executable

## Examples

### Example 1: Full Setup

**User**: "Setup git hooks for my Node.js project"

**Output**:
- Installs husky + lint-staged
- Creates pre-commit hook (lint, format, test)
- Creates pre-push hook (full tests)
- Creates commit-msg hook (conventional commits)

### Example 2: Python Project

**User**: "Setup pre-commit hooks for Python"

**Output**:
- Installs pre-commit framework
- Configures black, flake8, isort, mypy
- Adds pytest hook
- Installs hooks to .git/hooks/

## Best Practices

1. **Fast pre-commit**: Only run on changed files
2. **Comprehensive pre-push**: Full test suite before push
3. **Allow skip**: Provide --no-verify escape hatch
4. **Team consistency**: Commit hooks config to repo
5. **Clear feedback**: Show what's running and why it failed

## Changelog

### Version 1.0.0
- Husky setup for Node.js
- pre-commit framework for Python
- Manual hooks for any project
- Conventional Commits enforcement
- Secret detection

## Author

**GLINCKER Team**
- Repository: [claude-code-marketplace](https://github.com/GLINCKER/claude-code-marketplace)