Update merge-main-into-prs.yml

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

.github/workflows/merge-main-into-prs.yml

@@ -1,15 +1,14 @@
-# Ultralytics YOLOv5 🚀, AGPL-3.0 license
+# 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
+  # push:
+  #   branches:
+  #     - ${{ github.event.repository.default_branch }}
 
 jobs:
   Merge:
@@ -22,35 +21,51 @@ jobs:
           fetch-depth: 0
       - uses: actions/setup-python@v5
         with:
-          python-version: "3.11"
-          cache: "pip" # caching pip dependencies
+          python-version: "3.x"
+          cache: "pip"
       - name: Install requirements
         run: |
           pip install pygithub
-      - name: Merge main into PRs
+      - name: Merge default branch 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
+          
+          # Fetch the default branch name
+          default_branch_name = repo.default_branch
+          default_branch = repo.get_branch(default_branch_name)
+          
+          for pr in repo.get_pulls(state='open', sort='created'):
               try:
-                  # 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.")
+                  # Get full names for repositories and branches
+                  base_repo_name = repo.full_name
+                  head_repo_name = pr.head.repo.full_name
+                  base_branch_name = pr.base.ref
+                  head_branch_name = pr.head.ref
+
+                  # Check if PR is behind the default branch
+                  comparison = repo.compare(default_branch.commit.sha, pr.head.sha)
+                  
+                  if comparison.behind_by > 0:
+                      print(f"⚠️ PR #{pr.number} ({head_repo_name}:{head_branch_name} -> {base_repo_name}:{base_branch_name}) is behind {default_branch_name} by {comparison.behind_by} commit(s).")
+                      
+                      # Attempt to update the branch
+                      try:
+                          success = pr.update_branch()
+                          assert success, "Branch update failed"
+                          print(f"✅ Successfully merged '{default_branch_name}' into PR #{pr.number} ({head_repo_name}:{head_branch_name} -> {base_repo_name}:{base_branch_name}).")
+                      except Exception as update_error:
+                          print(f"❌ Could not update PR #{pr.number} ({head_repo_name}:{head_branch_name} -> {base_repo_name}:{base_branch_name}): {update_error}")
+                          print("   This might be due to branch protection rules or insufficient permissions.")
+                  else:
+                      print(f"✅ PR #{pr.number} ({head_repo_name}:{head_branch_name} -> {base_repo_name}:{base_branch_name}) is up to date with {default_branch_name}.")
               except Exception as e:
-                  print(f"Could not merge 'master' into PR #{pr.number} ({pr.head.ref}): {e}")
+                  print(f"❌ Could not process PR #{pr.number}: {e}")
+
         env:
-          GITHUB_TOKEN: ${{ secrets.PERSONAL_ACCESS_TOKEN }}
+          GITHUB_TOKEN: ${{ secrets.PERSONAL_ACCESS_TOKEN || secrets.GITHUB_TOKEN }}
           GITHUB_REPOSITORY: ${{ github.repository }}