claude-copy-to-main.yml

name: Claude Copy PR to Main

on:
  issue_comment:
    types: [created]

jobs:
  copy-to-main:
    name: Copy PR to Main
    if: |
      github.event_name == 'issue_comment' &&
      github.event.issue.pull_request &&
      contains(github.event.comment.body, '/claude copy')
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write
      issues: write
      id-token: write
    env:
      GH_TOKEN: ${{ secrets.PAT }}
      REPO: ${{ github.repository }}
      PR_NUMBER: ${{ github.event.issue.number }}
    steps:
      - name: Check commenter has write access
        env:
          COMMENTER: ${{ github.event.comment.user.login }}
        run: |
          PERMISSION=$(gh api repos/$REPO/collaborators/$COMMENTER/permission --jq .permission)
          if [[ "$PERMISSION" != "admin" && "$PERMISSION" != "write" ]]; then
            gh pr comment $PR_NUMBER --repo $REPO --body "❌ You do not have write access to use \`/claude copy\`."
            exit 1
          fi

      - name: Check PR is merged and targets non-main
        run: |
          PR_JSON=$(gh pr view $PR_NUMBER --repo $REPO --json baseRefName,mergedAt)
          PR_BASE=$(echo "$PR_JSON" | jq -r .baseRefName)
          PR_MERGED=$(echo "$PR_JSON" | jq -r .mergedAt)

          if [ "$PR_BASE" = "main" ]; then
            gh pr comment $PR_NUMBER --repo $REPO --body "❌ This PR already targets \`main\`. \`/claude copy\` only works on PRs targeting non-main branches."
            exit 1
          fi

          if [ "$PR_MERGED" = "null" ] || [ -z "$PR_MERGED" ]; then
            gh pr comment $PR_NUMBER --repo $REPO --body "❌ This PR has not been merged yet. \`/claude copy\` only works on merged PRs."
            exit 1
          fi

      - name: Checkout repository
        uses: actions/checkout@v6
        with:
          fetch-depth: 0
          token: ${{ secrets.PAT }}

      - name: Fetch PR head ref from fork
        run: |
          git fetch origin pull/$PR_NUMBER/head:pr-$PR_NUMBER-head

      - name: Run Claude Copy to Main
        uses: anthropics/claude-code-action@v1
        with:
          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
          trigger_phrase: "/claude copy"
          github_token: ${{ secrets.PAT }}
          prompt: |
            REPO: ${{ env.REPO }}
            PR NUMBER: ${{ env.PR_NUMBER }}

            You are a PR copy assistant. Your job is to apply the final changes from a merged PR onto a new branch based on `main` and create a new PR targeting `main`.

            The PR's commits originated from a fork and have been fetched locally as the branch: pr-${PR_NUMBER}-head

            STEPS:
            1. Get the PR details (title, body, and base branch):
               gh pr view $PR_NUMBER --repo $REPO --json title,body,baseRefName

            2. Configure git for committing (use the svcnvidia-nemo-ci service account since secrets.PAT belongs to it):
               git config user.name "svcnvidia-nemo-ci"
               git config user.email "svcnvidia-nemo-ci@nvidia.com"

            3. Create a new branch from `main`:
               git checkout main
               git pull origin main
               git checkout -b copy-pr-${PR_NUMBER}-to-main

            4. Generate a patch of the PR's final changes and apply it:
               MERGE_BASE=$(git merge-base origin/<baseRefName> pr-${PR_NUMBER}-head)
               git diff $MERGE_BASE pr-${PR_NUMBER}-head | git apply --3way
               (Replace <baseRefName> with the actual base branch name from step 1.)

               If the apply fails due to merge conflicts:
               a. Identify conflicted files: git diff --name-only --diff-filter=U
               b. For each conflicted file, read its contents to see the conflict markers
               c. Resolve the conflicts by favoring the `main` branch side when there is a genuine
                  conflict between the two sides. The goal is to bring the PR's changes into main
                  without overriding what is already on main.
               d. Stage the resolved files: git add <file>

            5. Commit the changes:
               git add -A
               git commit -m "Copy PR #${PR_NUMBER} to main"

            6. Push the new branch:
               git push origin copy-pr-${PR_NUMBER}-to-main

            7. Create a new PR targeting `main`:
               gh pr create --repo $REPO \
                 --base main \
                 --head copy-pr-${PR_NUMBER}-to-main \
                 --title "[Copy to main] <original PR title>" \
                 --body "🤖 **This PR was auto-generated by Claude** via the \`/claude copy\` command.\n\nCherry-picked from #${PR_NUMBER}.\n\n---\n\n<original PR body>"

            8. Comment on the original PR with a link to the newly created PR.

            IMPORTANT:
            - When resolving merge conflicts, favor `main` over the non-main branch. Do not override changes already on main.
            - Do NOT force push.
          claude_args: |
            --allowedTools "Bash(git:*),Bash(gh:*),Read,Edit"
            --model "claude-opus-4-6"