🛠️ Fix-it Felix - GitHub Action

Fix-it Felix is a GitHub Action that automatically fixes minor code quality issues (linting, formatting) in pull requests. It's designed to be configurable, safe, and work across multiple repositories in your organization.

✨ Features

• 🔧 Multiple Fixers: Support for ESLint, Prettier, and Markdownlint
• 🎨 Custom Commands: Use your own npm scripts or custom commands
• ⚙️ Configurable: Per-repository configuration via .felixrc.json
• 🤖 Auto-commit: Automatically commits fixes to PR branches
• 🛡️ Safety First: Built-in safeguards against infinite loops
• 🔍 Dry-run Mode: Preview changes without committing
• 🚫 Skip Control: Label-based opt-out mechanism
• 📄 Draft PR Control: Optionally skip draft PRs
• 🍴 Fork Friendly: Handles forked PRs gracefully

🚀 Quick Start

Basic Usage

Create .github/workflows/fix-it-felix.yml in your repository:

name: Fix-it Felix

on:
  pull_request:
    types: [opened, synchronize, reopened]

jobs:
  autofix:
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write

    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          fetch-depth: 0

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      # ⚠️ REQUIRED: Install dependencies before running Felix
      # This ensures your project's exact tool versions and configs are used
      - name: Install dependencies
        run: npm ci

      - name: Run Fix-it Felix
        uses: launchdarkly-labs/fix-it-felix@v1
        with:
          fixers: 'eslint,prettier'
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

📖 Inputs

Input	Description	Required	Default
fixers	Comma-separated list of fixers to run	No	eslint,prettier
commit_message	Commit message for auto-fix commits	No	🤖 Fix-it Felix: Auto-fixed code quality issues
config_path	Path to Felix configuration file	No	.felixrc.json
dry_run	Run in dry-run mode (comment instead of commit)	No	false
skip_label	PR label that skips Felix processing	No	skip-felix
skip_draft_prs	Skip processing draft pull requests	No	false
allowed_bots	Comma-separated list of bot names Felix should run against	No	``
paths	Comma-separated list of paths to run fixers on	No	.

📤 Outputs

Output	Description
fixes_applied	Whether any fixes were applied (true/false)
changed_files	Comma-separated list of files that were modified

🔧 Supported Fixers

ESLint

• Default Command: npx eslint --fix .
• Extensions: .js, .jsx, .ts, .tsx, .vue
• Config: Respects existing ESLint configuration
• Custom Commands: Override with your own npm scripts or commands

Prettier

• Default Command: npx prettier --write
• Extensions: .js, .jsx, .ts, .tsx, .json, .css, .scss, .md, .yml, .yaml
• Config: Respects existing Prettier configuration
• Custom Commands: Override with your own npm scripts or commands

Markdownlint

• Default Command: npx markdownlint-cli2 --fix
• Extensions: .md, .markdown
• Config: Respects existing Markdownlint configuration
• Custom Commands: Override with your own npm scripts or commands

⚙️ Configuration

Basic Setup

Control Felix through action inputs:

- name: Run Fix-it Felix
  uses: launchdarkly-labs/fix-it-felix@v1
  with:
    fixers: 'eslint,prettier' # Which tools to run
    paths: 'src,docs' # Which directories to process
    dry_run: false # Set to true to preview changes

Repository Configuration

For advanced settings, create a .felixrc.json file:

{
  "fixers": ["eslint", "prettier"],
  "paths": ["src", "docs"],
  "ignore": ["node_modules/**", "dist/**"],
  "eslint": {
    "configFile": ".eslintrc.js",
    "extensions": [".js", ".jsx", ".ts", ".tsx"]
  },
  "prettier": {
    "extensions": [".js", ".jsx", ".ts", ".tsx", ".json", ".md"]
  }
}

Custom Commands

Use your own npm scripts instead of built-in commands:

{
  "eslint": {
    "command": ["npm", "run", "lint:fix"],
    "appendPaths": true // Append file paths for performance
  },
  "prettier": {
    "command": ["npm", "run", "format"],
    "appendPaths": false // Run script as-is
  }
}

📚 Full Configuration Guide →

📚 Documentation

• Configuration Guide - Complete configuration reference
• Examples - Workflow examples and sample configs

🛡️ Safety Features

Infinite Loop Protection

• Detects commits made by Felix or other bots
• Skips processing if last commit was automated
• Prevents endless fix-commit cycles
• Exception: Bots listed in allowed_bots will bypass this protection

Fork Handling

• Automatically detects forked PRs
• Skips processing (cannot commit to forks with default token)
• Logs appropriate messages

Draft PR Handling

By default, Felix processes draft PRs just like regular PRs. You can configure Felix to skip draft PRs entirely:

- name: Run Fix-it Felix
  uses: launchdarkly/fix-it-felix-action@v1
  with:
    skip_draft_prs: true

This is useful when you want to:

• Prevent commits on work-in-progress PRs
• Let developers refine their changes before auto-fixing
• Reduce action runs during development

Skip Mechanisms

• Label-based: Add skip-felix label to PR
• Draft PRs: Set skip_draft_prs: true to skip draft PRs
• Configuration: Set fixers: [] in .felixrc.json
• Event-based: Only runs on specific PR events

🔍 Dry-run Mode

Test Felix without committing changes:

- name: Run Fix-it Felix (Dry Run)
  uses: launchdarkly-labs/fix-it-felix@v1
  with:
    fixers: 'eslint,prettier'
    dry_run: true
  env:
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

In dry-run mode, Felix will:

• Run all configured fixers
• Generate a PR comment with proposed changes
• Not commit or push any changes

📝 Examples

See the examples/ directory for workflow examples:

• Basic usage - Simple setup
• Advanced usage - Configuration with dry-run
• Configuration file - Example .felixrc.json

🔧 Development

Prerequisites

• Node.js 20+
• npm

Setup

npm install

Build

npm run build

Test

npm test

Package for Release

npm run package

🤝 Contributing

1. Create a feature branch
2. Make your changes
3. Add tests if applicable
4. Run npm run package to update the distribution
5. Submit a pull request

🎯 Roadmap

• Support for more fixers (stylelint, gofmt, black, etc.)
• Custom fixer support ✅ Completed - Use custom commands
• Monorepo support
• Slack/Discord notifications
• Performance optimizations

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