.github/workflows/easy-cp.yml

# Copyright 2023 The Flutter Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

name: Cherry-pick Labeled PR to Release Branch

on:
  pull_request:
    branches: master
    types: [labeled]

permissions: write-all

jobs:
  cherrypick_to_release:
    name: cherrypick_to_release
    runs-on: ubuntu-latest
    if: |
      (github.event.label.name == format('cp{0} beta', ':') || github.event.label.name == format('cp{0} stable', ':')) &&
      (github.event.pull_request.merged == true)
    steps:
      - name: Get Release Channel
        run: |
          echo "CHANNEL=$(echo ${{ github.event.label.name }} | cut -d ':' -f 2 | xargs)" >> $GITHUB_ENV
      - name: Get Release Candidate Branch
        run: |
          RELEASE_BRANCH=$(curl https://raw.githubusercontent.com/flutter/flutter/$CHANNEL/bin/internal/release-candidate-branch.version)
          echo "RELEASE_BRANCH=$(echo $RELEASE_BRANCH | tr -d '\n')" >> $GITHUB_ENV
      - name: Get Cherry Pick PR
        run: |
          echo "COMMIT_SHA=$(echo ${{ github.event.pull_request.merge_commit_sha }})" >> $GITHUB_ENV
      - name: Checkout Flutter Repo
        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11
        with:
          repository: flutter/flutter
          token: ${{ github.token }}
          path: flutter
          ref: master
          # Checkout all history commits on master branch, so that the cp commit is a known object
          fetch-depth: 0
      # use same name when checking out branch, since the marketplace action does a hard reset.
      - name: Attempt CP
        id: attempt-cp
        working-directory: ./flutter
        run: |
          git config user.name "GitHub Actions Bot"
          git config user.email "<>"
          git fetch origin $RELEASE_BRANCH
          git fetch origin master
          git checkout -b $RELEASE_BRANCH --track origin/$RELEASE_BRANCH
          git cherry-pick $COMMIT_SHA
      # TODO(xilaizhang): remove this step once the template is available on release branches.
      - name: Get CP Template
        run: |
          curl -o PULL_REQUEST_CP_TEMPLATE.md https://raw.githubusercontent.com/flutter/flutter/master/.github/PR_TEMPLATE/PULL_REQUEST_CP_TEMPLATE.md
      - name: Create PR on CP success
        if: ${{ steps.attempt-cp.conclusion == 'success' }}
        uses: peter-evans/create-pull-request@153407881ec5c347639a548ade7d8ad1d6740e38
        with:
          base: ${{ env.RELEASE_BRANCH }}
          branch: cp-${{ env.CHANNEL }}-${{ env.COMMIT_SHA }}
          path: flutter
          token: ${{ secrets.FLUTTERACTIONSBOT_CP_TOKEN }}
          labels: |
            cp: review
          title: '[${{ env.CHANNEL }}-cherrypick] cherrypicks commit ${{ env.COMMIT_SHA }} from PR ${{ github.event.pull_request.title }}'
          body-path: PULL_REQUEST_CP_TEMPLATE.md
      - name: Leave Comment on CP failure
        if: ${{ failure() && steps.attempt-cp.conclusion == 'failure' }}
        run: |
          FAILURE_MSG="Failed to create CP due to merge conflicts.<br>"
          FAILURE_MSG+="You will need to create the PR manually. See [the cherrypick wiki](https://github.com/flutter/flutter/wiki/Flutter-Cherrypick-Process) for more info."
          gh pr comment ${{ github.event.pull_request.number }} -R flutter/flutter -b "${FAILURE_MSG}"
        env:
          GITHUB_TOKEN: ${{ secrets.FLUTTERMIRRORINGBOT_TOKEN }}