fast-forward.yml

name: Fast Forward Merge

on:
  issue_comment:
    types: [ created ]

jobs:
  fast_forward_job:
    name: Fast Forward
    if: |
      (github.event.issue.pull_request != '') &&
      github.event.comment.body == '/fast-forward'
    runs-on: ubuntu-latest
    steps:
      - uses: actions-cool/check-user-permission@v2
        id: has_permission
        with:
          require: 'write'

      - name: Comment PR
        uses: thollander/actions-comment-pull-request@v3
        if: steps.has_permission.outputs.require-result != 'true'
        with:
          pr-number: ${{ github.event.issue.number }}
          message: |
            You have no write permission on this repository

      - name: Exit if no write permission
        if: steps.has_permission.outputs.require-result != 'true'
        run: exit 1

      - uses: actions/github-script@v7
        id: current_pr
        with:
          github-token: ${{ secrets.FAST_FORWARD_TOKEN }}
          script: |
            return github.rest.pulls.get({
              pull_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
            })

      - run: echo $prJSON
        env:
          prJSON: ${{ toJSON(fromJSON(steps.current_pr.outputs.result).data) }}

      - name: Comment PR
        uses: thollander/actions-comment-pull-request@v3
        if: fromJSON(steps.current_pr.outputs.result).data.mergeable_state != 'clean'
        with:
          pr-number: ${{ github.event.issue.number }}
          message: |
            The PR mergeable_state needs to be clean, was: ${{ fromJSON(steps.current_pr.outputs.result).data.mergeable_state }}

      - name: Exit if PR mergeable_state is not clean
        if: fromJSON(steps.current_pr.outputs.result).data.mergeable_state != 'clean'
        run: exit 1

      # To use this repository's private action, you must check out the repository
      - name: Checkout
        uses: actions/checkout@v4

      - name: Fast Forward PR
        id: ff-action
        uses: endre-spotlab/fast-forward-js-action@2.1
        with:
          GITHUB_TOKEN: ${{ secrets.FAST_FORWARD_TOKEN }}
          success_message: 'Success! Fast forwarded ***target_base*** to ***source_head***! ```git checkout target_base && git merge source_head --ff-only``` '
          failure_message: 'Failed! Cannot do fast forward!'