FormatPullRequest.yml

name: "FormatPullRequest"

on:
  workflow_call:
    inputs:
      directory:
        description: "The directory on which ITensorFormatter needs to be run"
        default: "."
        required: false
        type: string
      julia-version:
        description: "Julia version"
        default: "1"
        required: false
        type: string
      trigger:
        description: "Comment trigger phrase for on-demand formatting"
        default: "/format"
        required: false
        type: string

jobs:
  format-pull-request:
    name: "FormatPullRequest"
    runs-on: ubuntu-latest
    if: |
      github.event_name != 'issue_comment' || (
        github.event.issue.pull_request != null &&
        contains(fromJSON('["OWNER", "COLLABORATOR", "MEMBER"]'), github.event.comment.author_association) &&
        contains(github.event.comment.body, inputs.trigger)
      )
    permissions:
      contents: write
      pull-requests: write
    steps:
      - name: "Get PR branch"
        if: github.event_name == 'issue_comment'
        id: pr
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          HEAD_REF=$(gh api repos/${{ github.repository }}/pulls/${{ github.event.issue.number }} --jq '.head.ref')
          echo "head_ref=$HEAD_REF" >> $GITHUB_OUTPUT

      - uses: actions/checkout@v6
        with:
          ref: ${{ steps.pr.outputs.head_ref }}
          token: ${{ secrets.FORMATPULLREQUEST_PAT || secrets.GITHUB_TOKEN }}

      - name: "Setup Julia ${{ inputs.julia-version }}"
        uses: julia-actions/setup-julia@v3
        with:
          version: "${{ inputs.julia-version }}"
          arch: "${{ runner.arch }}"

      - uses: julia-actions/cache@v3

      - name: "Install ITensorFormatter"
        run: |
          julia -e '
            using Pkg
            Pkg.Registry.add("General")
            Pkg.Registry.add(; url = "https://github.com/ITensor/ITensorRegistry")
            Pkg.Apps.add("ITensorFormatter")
          '
          echo "$HOME/.julia/bin" >> $GITHUB_PATH

      - name: "Run ITensorFormatter"
        env:
          DIRECTORY: ${{ inputs.directory }}
        run: |
          itpkgfmt "$DIRECTORY"
        continue-on-error: true

      - name: "Detect formatting changes"
        id: changes
        shell: bash
        run: |
          # Include newly created (untracked) files in the change detection.
          git add -N .
          if ! git diff --quiet; then
            echo "changes=true" >> "$GITHUB_OUTPUT"
          else
            echo "changes=false" >> "$GITHUB_OUTPUT"
          fi

      # Resolve the PAT owner so commit author, PR committer, and reaction
      # attribution all match the identity the token authenticates as.
      # Falls back to github-actions[bot] when FORMATPULLREQUEST_PAT is
      # unset (forks, etc.).
      - name: "Detect token owner"
        id: token-owner
        env:
          GH_TOKEN: ${{ secrets.FORMATPULLREQUEST_PAT || secrets.GITHUB_TOKEN }}
        shell: bash
        run: |
          json=$(gh api user 2>/dev/null || echo '{}')
          login=$(echo "$json" | jq -r '.login // ""')
          id=$(echo "$json" | jq -r '.id // ""')
          if [ -n "$login" ]; then
            name="$login"
            email="${id}+${login}@users.noreply.github.com"
          else
            name="github-actions[bot]"
            email="github-actions[bot]@users.noreply.github.com"
          fi
          echo "name=$name" >> "$GITHUB_OUTPUT"
          echo "email=$email" >> "$GITHUB_OUTPUT"

      # issue_comment mode: commit directly to the PR branch
      - name: "Commit and push changes"
        if: github.event_name == 'issue_comment' && steps.changes.outputs.changes == 'true'
        env:
          GIT_NAME: ${{ steps.token-owner.outputs.name }}
          GIT_EMAIL: ${{ steps.token-owner.outputs.email }}
        run: |
          git config user.name "$GIT_NAME"
          git config user.email "$GIT_EMAIL"
          git add -A
          git commit -m "Format .jl files (ITensorFormatter)"
          git push

      # issue_comment mode: react to the triggering comment
      - name: "React to comment"
        if: github.event_name == 'issue_comment'
        uses: peter-evans/create-or-update-comment@v5
        with:
          token: ${{ secrets.FORMATPULLREQUEST_PAT || secrets.GITHUB_TOKEN }}
          comment-id: ${{ github.event.comment.id }}
          reactions: '+1'

      # schedule/dispatch mode: bump version and open a new PR
      - name: "Bump patch version"
        if: github.event_name != 'issue_comment' && steps.changes.outputs.changes == 'true'
        shell: julia --color=yes {0}
        run: |
          import Pkg
          project_file = "Project.toml"
          project = Pkg.Types.read_project(project_file)
          project.version = Base.nextpatch(project.version)
          Pkg.Types.write_project(project, project_file)

      - name: "Stage changes (including new files)"
        if: github.event_name != 'issue_comment' && steps.changes.outputs.changes == 'true'
        shell: bash
        run: git add -A

      - name: "Create pull request"
        if: github.event_name != 'issue_comment' && steps.changes.outputs.changes == 'true'
        id: cpr
        uses: peter-evans/create-pull-request@v8
        with:
          token: ${{ secrets.FORMATPULLREQUEST_PAT || secrets.GITHUB_TOKEN }}
          commit-message: "Format .jl files (ITensorFormatter)"
          title: "Automatic ITensorFormatter run"
          branch: auto-format-pr
          delete-branch: true
          author: "${{ steps.token-owner.outputs.name }} <${{ steps.token-owner.outputs.email }}>"
          committer: "${{ steps.token-owner.outputs.name }} <${{ steps.token-owner.outputs.email }}>"

      - name: "Check outputs"
        if: github.event_name != 'issue_comment'
        run: |
          echo "Pull Request Number - ${{ steps.cpr.outputs.pull-request-number }}"
          echo "Pull Request URL - ${{ steps.cpr.outputs.pull-request-url }}"