Auto fix conflicts

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

• #16290

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Why this happens

Codex creates its branch from a snapshot of main at task start. If main moves forward before Codex finishes (even a README edit or an auto-generated commit), the PR lands with conflicts — even though you never touched those files. It's a race condition between Codex's branch base and the current main.

Workaround that worked for me

I created a GitHub Actions workflow that auto-resolves conflicts by merging main into the Codex branch with -X theirs (keeping Codex's changes):

name: Auto Fix Conflicts

on:
  pull_request:
    types: [opened, synchronize, reopened]
  workflow_dispatch:
    inputs:
      branch:
        description: "Branch to fix"
        required: false
        default: ""

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

    steps:
      - name: Checkout repo
        uses: actions/checkout@v5
        with:
          ref: ${{ github.event.inputs.branch || github.head_ref }}
          token: ${{ secrets.GITHUB_TOKEN }}
          fetch-depth: 0

      - name: Configure git identity
        run: |
          git config user.name "conflict-bot"
          git config user.email "bot@example.com"

      - name: Fetch base branch
        run: git fetch origin main

      - name: Try auto-merge (prefer incoming changes)
        run: git merge -X theirs origin/main || true

      - name: Detect conflicts
        id: conflicts
        run: |
          files=$(git diff --name-only --diff-filter=U)
          echo "files=$files" >> $GITHUB_OUTPUT

      - name: Auto resolve conflicts (fallback)
        if: steps.conflicts.outputs.files != ''
        run: |
          for file in ${{ steps.conflicts.outputs.files }}; do
            echo "Resolving $file"
            git checkout --theirs $file
            git add $file
          done

      - name: Commit & push changes
        run: |
          git add .
          git commit -m "🤖 Auto-resolved merge conflicts" || echo "No changes"
          git push

Key things that tripped me up:

• permissions: contents: write is required or the push silently fails with 403
• git config must come before the merge step, not just before the commit
• Use actions/checkout@v5 to avoid the Node 20 deprecation warning

Would love to see Codex handle this natively — maybe by rebasing its branch on main right before opening the PR.

This feature request hasn't received enough upvotes, so I'm going to close it.