merge_on_comment.yml

name: 'Merge a PR on a comment'

on:
  issue_comment:
    types: [created]

jobs:
  is_merge_command:
    if: ${{ github.event.issue.pull_request }}
    runs-on: 'ubuntu-latest'
    outputs:
      is_merge_command: ${{ steps.set_is_merge_command.outputs.is_merge_command }}
    steps:
      - name: Set is_merge_command
        id: set_is_merge_command
        env:
          COMMENT_BODY: ${{ github.event.comment.body }}
        run: |
          ruby -e '
            is_merge_command = ENV["COMMENT_BODY"].match?(%r!\A/merge\s*\z!)
            puts "is_merge_command=#{is_merge_command}"
          ' >> $GITHUB_OUTPUT
  merge:
    needs: is_merge_command
    if: ${{ needs.is_merge_command.outputs.is_merge_command == 'true' }}
    runs-on: 'ubuntu-latest'
    permissions:
      pull-requests: write
      contents: write
    steps:
      - uses: actions/checkout@v4
        with:
          filter: 'blob:none'
          fetch-depth: 0
          ref: main
      - uses: ruby/setup-ruby@v1
        with:
          ruby-version: '3.3'
          bundler-cache: false
      - name: Fetch PR information
        id: pr_info
        env:
          PR_NUMBER: ${{ github.event.issue.number }}
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GH_REPO: ${{ github.repository }}
        run: |
          pr="$(gh api -H "Accept: application/vnd.github+json" -H "X-GitHub-Api-Version: 2022-11-28" /repos/${GH_REPO}/pulls/${PR_NUMBER})"
          author="$(echo "$pr" | jq -r .user.login)"
          head_sha="$(echo "$pr" | jq -r .head.sha)"
          base_sha="$(echo "$pr" | jq -r .base.sha)"

          echo "author=$author" >> $GITHUB_OUTPUT
          echo "head_sha=$head_sha" >> $GITHUB_OUTPUT
          echo "base_sha=$base_sha" >> $GITHUB_OUTPUT
      - name: Changed gems and non gem files
        env:
          BASE_SHA: ${{ steps.pr_info.outputs.base_sha }}
          HEAD_SHA: ${{ steps.pr_info.outputs.head_sha }}
        id: changes
        run: |
          ruby .github/workflows/pr_bot/changed_files.rb
      - name: Merge the PR
        env:
          BASE_SHA: ${{ steps.pr_info.outputs.base_sha }}
          HEAD_SHA: ${{ steps.pr_info.outputs.head_sha }}
          PR_AUTHOR: ${{ steps.pr_info.outputs.author }}
          CHANGED_GEMS: ${{ steps.changes.outputs.gems }}
          CHANGED_NON_GEMS: ${{ steps.changes.outputs.non_gems }}

          COMMENTED_BY: ${{ github.event.comment.user.login }}
          PR_NUMBER: ${{ github.event.issue.number }}
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GH_REPO: ${{ github.repository }}
        run: |
          ruby .github/workflows/pr_bot/check_merge_ability.rb "$CHANGED_GEMS" "$CHANGED_NON_GEMS" "$PR_NUMBER"
          gh pr merge "$PR_NUMBER" --repo "$GH_REPO" --squash --match-head-commit $HEAD_SHA