cherry-pick-wp-release.yml

name: Auto Cherry-Pick

on:
    pull_request:
        types: [closed, labeled]
        branches:
            - try/cherry-pick-automation-trunk # To be replaced with "trunk".

jobs:
    cherry-pick:
        runs-on: ubuntu-latest
        if: github.event.pull_request.merged == true
        steps:
            - name: Checkout repository
              uses: actions/checkout@v2
              with:
                  fetch-depth: 0

            - name: Set up Git
              run: |
                  git config --global user.name "Gutenberg Repository Automation"
                  git config --global user.email "gutenberg@wordpress.org"

            - name: Determine if label should trigger cherry-pick
              id: label-check
              run: |
                  LABELS=$(jq -r '.pull_request.labels[].name' "$GITHUB_EVENT_PATH")
                  for LABEL in $LABELS; do
                    if [[ "$LABEL" =~ ^Backport\ to\ WP\ ([0-9]+\.[0-9]+)\ Beta/RC$ ]]; then
                      VERSION=${BASH_REMATCH[1]}
                      echo "::set-output name=cherry_pick::true"
                      echo "::set-output name=version::$VERSION"
                      exit 0
                    fi
                  done
                  echo "::set-output name=cherry_pick::false"

            - name: Cherry-pick the commit
              id: cherry-pick
              if: steps.label-check.outputs.cherry_pick == 'true'
              run: |
                  TARGET_BRANCH="wp/${{ steps.label-check.outputs.version }}"
                  COMMIT_SHA=$(jq -r '.pull_request.merge_commit_sha' "$GITHUB_EVENT_PATH")
                  git checkout $TARGET_BRANCH
                  git cherry-pick $COMMIT_SHA || echo "cherry-pick-failed" > result
                  if [ -f result ] && grep -q "cherry-pick-failed" result; then
                    echo "::set-output name=conflict::true"
                    git cherry-pick --abort
                  else
                    git push origin $TARGET_BRANCH
                    echo "::set-output name=conflict::false"
                  fi

            - name: Remove cherry-pick label
              if: steps.label-check.outputs.cherry_pick == 'true' && steps.cherry-pick.outputs.conflict == 'false'
              uses: actions/github-script@v6
              with:
                  script: |
                      const prNumber = ${{ github.event.pull_request.number }};
                      const label = `Backport to WP ${{ steps.label-check.outputs.version }} Beta/RC`;
                      await github.issues.removeLabel({
                        owner: context.repo.owner,
                        repo: context.repo.repo,
                        issue_number: prNumber,
                        name: label
                      });

            - name: Comment on the PR
              if: steps.label-check.outputs.cherry_pick == 'true' && steps.cherry-pick.outputs.conflict == 'false'
              uses: actions/github-script@v6
              with:
                  script: |
                      const prNumber = ${{ github.event.pull_request.number }};
                      const commitSha = '${{ steps.cherry-pick.outputs.commit_sha }}';
                      const targetBranch = `wp/${{ steps.label-check.outputs.version }}`;
                      await github.issues.createComment({
                        owner: context.repo.owner,
                        repo: context.repo.repo,
                        issue_number: prNumber,
                        body: `I just cherry-picked this PR to the ${targetBranch} branch to get it included in the next release: ${commitSha}`
                      });

            - name: Comment on the PR about conflict
              if: steps.label-check.outputs.cherry_pick == 'true' && steps.cherry-pick.outputs.conflict == 'true'
              uses: actions/github-script@v6
              with:
                  script: |
                      const prNumber = ${{ github.event.pull_request.number }};
                      const targetBranch = `wp/${{ steps.label-check.outputs.version }}`;
                      await github.issues.createComment({
                        owner: context.repo.owner,
                        repo: context.repo.repo,
                        issue_number: prNumber,
                        body: `There was a conflict while trying to cherry-pick the commit to the ${targetBranch} branch. Please resolve the conflict manually and create a PR to the ${targetBranch} branch.`
                      });