merge-main-into-prs.yml

# Ultralytics YOLO 🚀, AGPL-3.0 license
# Automatically merges repository 'main' branch into all open PRs to keep them up-to-date
# Action runs on updates to main branch so when one PR merges to main all others update

name: Merge main into PRs

on:
  workflow_dispatch:
  push:
    branches:
      - main
      - master
  
jobs:
  Merge:
    if: github.repository == 'ultralytics/yolov5'
    runs-on: ubuntu-latest
    steps:
    - name: Checkout repository
      uses: actions/checkout@v4
      with:
        fetch-depth: 0
    - uses: actions/setup-python@v5
      with:
        python-version: "3.11"
        cache: "pip" # caching pip dependencies
    - name: Install requirements
      run: |
        pip install pygithub
    - name: Merge main into PRs
      shell: python
      run: |
        from github import Github
        import os
        
        # Authenticate with the GitHub Token
        g = Github(os.getenv('GITHUB_TOKEN'))
        
        # Get the repository dynamically
        repo = g.get_repo(os.getenv('GITHUB_REPOSITORY'))
        
        # List all open pull requests
        open_pulls = repo.get_pulls(state='open', sort='created')
        
        for pr in open_pulls:
            # Compare PR head with main to see if it's behind
            try:
                comparison = repo.compare(pr.base.ref, pr.head.ref)  # Ensure correct order of base and head
                if comparison.behind_by > 0:
                    # Merge main into the PR branch
                    success = pr.update_branch()
                    assert success, "Branch update failed"
                    print(f"Merged 'master' into PR #{pr.number} ({pr.head.ref}) successfully.")
            except Exception as e:
                print(f"Could not merge 'master' into PR #{pr.number} ({pr.head.ref}): {e}")
      env:
        GITHUB_TOKEN: ${{ secrets.PERSONAL_ACCESS_TOKEN }}
        GITHUB_REPOSITORY: ${{ github.repository }}