git-blame-ignore

CLI that auto-detects bulk-change commits (prettier, lint autofix, mass renames) and manages your .git-blame-ignore-revs file — so git blame stays useful.

🎯 Problem

After running prettier, eslint --fix, or mass renames, git blame becomes useless for affected files — every line shows the formatting commit instead of who actually wrote the code. Git has .git-blame-ignore-revs natively, but:

• Manual SHA hunting — you have to find the commit SHA yourself
• No auto-detection — nobody wants to scan git log for bulk commits
• File management is tedious — add/remove/list entries manually

✨ Features

• Auto-detection - Scans git history for bulk-change commits using smart heuristics
• Interactive management - Easy init wizard to scan and select commits
• Command-line interface - Simple commands for all operations
• GitHub compatible - Works with GitHub's native .git-blame-ignore-revs support
• Validation - Checks that all SHAs are valid commits

🚀 Installation

npm install -g git-blame-ignore

📖 Usage

Interactive Setup

git-blame-ignore init

Scans for bulk-change commits and lets you select which ones to ignore interactively.

Commands

Scan for bulk commits (dry run)

git-blame-ignore scan
# Output:
# 🔍 Found 3 bulk-change commits:
#   1. a1b2c3d [85/100] Run prettier on all files
#      📁 47 files changed, 📝 2,841 lines changed
#      📅 2026-05-20 | Whitespace: 92%

Add a specific commit

git-blame-ignore add a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6q7r8s9t0u

List current entries

git-blame-ignore list
# Output:
# 📋 .git-blame-ignore-revs (3 entries):
#   1. a1b2c3d - Run prettier on all files
#      📅 2026-05-20

Remove an entry

git-blame-ignore remove a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6q7r8s9t0u

Validate entries

git-blame-ignore check
# Output:
# ✅ Valid entries: 3
# ❌ Invalid entries: 0

🔧 How It Works

Detection Algorithm

The tool uses a scoring system to identify bulk-change commits:

• Files changed: 20+ files = +30 points, 50+ files = +50 points
• Message matching: "prettier", "format", "lint", "rename" = +20 points each
• Whitespace ratio: >80% whitespace changes = +20 points
• Lines per file: <5 lines per file = +10 points (indicates formatting)

Commits with a score ≥ 40 are suggested for ignoring.

File Format

Creates and manages .git-blame-ignore-revs in the standard format:

# a1b2c3d4 Run prettier on all files (auto-detected by git-blame-ignore)
a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6q7r8s9t0u

# e4f5g6h7 eslint --fix (auto-detected by git-blame-ignore)
e4f5g6h7i8j9k0l1m2n3o4p5q6r7s8t9u0v1w2x3

🏗️ Development

# Clone and install
git clone https://github.com/sulthonzh/git-blame-ignore.git
cd git-blame-ignore
npm install

# Run in development mode
npm run dev

# Build for production
npm run build

# Run tests
npm test

# Lint code
npm run lint

📄 License

MIT License - see LICENSE file for details.

🔗 Related

• Git blame documentation
• GitHub blame ignore documentation
• git-blame-ignore-revs file format