reusable-generate-commit-message-v1.yml

##
# A reusable workflow that detects when the `gutenberg.sha` value changes in the `package.json` file.
##
name: Detect hash change (reusable)

on:
  workflow_call:
    inputs:
      previous-hash:
        description: 'The previous commit SHA value.'
        required: true
        type: 'string'
      new-hash:
        description: 'The new commit hash value.'
        required: true
        type: 'string'

# Disable permissions for all available scopes by default.
# Any needed permissions should be configured at the job level.
permissions: {}

jobs:
  # Drafts a commit message containing a detailed list of changes being merged.
  #
  # Performs the following steps:
  # - Downloads the changelog artifact.
  # - Builds a commit message.
  # - Uploads the commit message as an artifact.
  # - Saves the pull request number to a text file.
  # - Uploads the pull request number as an artifact.
  generate-commit-message:
    name: Generate commit message
    runs-on: ubuntu-24.04
    permissions:
      contents: read

    steps:
      - name: Download changelog artifact
        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
        with:
          name: changelog.txt
          skip-decompress: true

      - name: Build commit message
        env:
          BASE_SHA: ${{ inputs.previous-hash }}
          HEAD_SHA: ${{ inputs.new-hash }}
        run: |
          {
            printf 'Editor: Bump pinned hash for the Gutenberg repository.\n\n'
            printf "This updates the pinned hash from the gutenberg from \`%s\` to \`%s\`.\n\n" "$BASE_SHA" "$HEAD_SHA"

            if [ "$HAS_CHANGES" = "false" ]; then
              printf '> [!WARNING]\n'
              printf '> No pull request references were found in the commits between the two hashes. Please verify the hash range is correct.\n\n'
            else
              printf 'The following changes are included:\n\n'
              cat changelog.txt
              printf '\n'
            fi

            printf 'A full list of changes can be found on GitHub: https://github.com/WordPress/gutenberg/compare/%s...%s.\n\n' "$BASE_SHA" "$HEAD_SHA"
            printf 'See #64595, #64393.\n'
          } > commit-message.md

      - name: Upload commit message as an artifact
        uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
        with:
          name: commit-message
          path: commit-message.md

      - name: Save PR number
        run: |
          mkdir -p ./pr-number
          echo "${EVENT_NUMBER}" > ./pr-number/NR
        env:
          EVENT_NUMBER: ${{ github.event.number }}

      # Uploads the PR number as an artifact for the Pull Request Commenting workflow to download and then
      # leave a comment detailing how to test the PR within WordPress Playground.
      - name: Upload PR number as artifact
        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
        with:
          name: pr-number
          path: pr-number/