check_pr_scope.yml

name: Check PR Scope

on:
  pull_request:
    types: [opened, synchronize, reopened, edited]

jobs:
  check_scope:
    runs-on: ubuntu-latest
    outputs: # Define outputs for the job
      outcome: ${{ steps.check_scope_step.outcome }}
    steps:
      - uses: actions/checkout@v3
        with:
          fetch-depth: 0 # Fetch all history for all branches and tags

      - name: Get PR title
        id: pr_title
        run: echo "title=$(jq -r .pull_request.title \"$GITHUB_EVENT_PATH\")" >> $GITHUB_OUTPUT

      - name: Get changed files
        id: changed_files
        run: |
          files=$(git diff --name-only origin/${{ github.base_ref }}...origin/${{ github.head_ref }})
          echo "files<<EOF" >> $GITHUB_OUTPUT
          echo "$files" >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT

      - name: Check PR scope
        id: check_scope_step # Add id to this step
        run: |
          pr_title="${{ steps.pr_title.outputs.title }}"
          changed_files="${{ steps.changed_files.outputs.files }}"

          echo "PR Title: $pr_title"
          echo "Changed Files:"
          echo "$changed_files"

          # Extract scope from PR title (e.g., "fix(scope1,scope2): ...")
          pr_scopes_str=$(echo "$pr_title" | grep -oP '^\w+\(\K[^\)]+' || echo "")
          IFS=',' read -r -a pr_scopes <<< "$pr_scopes_str"
          # Trim whitespace from scopes
          pr_scopes=($(for scope in "${pr_scopes[@]}"; do echo "$scope" | xargs; done))

          if [ ${#pr_scopes[@]} -eq 0 ] && [[ "$pr_scopes_str" != "*" ]]; then
            error_message="PR title does not contain a valid scope. Please use the format 'type(scope): message' or 'type(*): message'."
            echo "::error::$error_message"
            comment_body="**Scope Check Failed!** 🚨\n\n${error_message}\n\nExample: \`feat(my-scope): add new feature\` or \`fix(*): resolve an issue\`."
            echo "comment_body=$comment_body" >> $GITHUB_ENV
            exit 1
          fi
          echo "PR Scopes: ${pr_scopes[@]}"

          # Load scope rules
          if [ ! -f "scope-rules.json" ]; then
            echo "::error::scope-rules.json not found."
            exit 1
          fi
          rules=$(cat scope-rules.json | jq -r '.rules')

          required_scopes=()
          while IFS= read -r file; do
            matched_scope=""
            for i in $(seq 0 $(($(echo "$rules" | jq length) - 1))); do
              pattern=$(echo "$rules" | jq -r ".[$i].pattern")
              scope_template=$(echo "$rules" | jq -r ".[$i].scope")

              if [[ "$file" =~ $pattern ]]; then
                # Handle scope template with capture groups (e.g., $1)
                if [[ "$scope_template" == "\$1" ]]; then
                  # BASH_REMATCH[0] is the full match, BASH_REMATCH[1] is the first capture group
                  matched_scope="${BASH_REMATCH[1]}"
                else
                  matched_scope="$scope_template"
                fi
                break
              fi
            done

            if [ -n "$matched_scope" ]; then
              # Add to required_scopes if not already present
              if [[ ! " ${required_scopes[@]} " =~ " ${matched_scope} " ]]; then
                required_scopes+=("$matched_scope")
              fi
            else
              # If no rule matches, consider it an error or a default scope based on requirements
              # For now, let's assume if a file doesn't match any rule, it's an issue.
              # Or, define a default scope in scope-rules.json like { "pattern": ".*", "scope": "default" }
              echo "::warning::No matching scope rule for file: $file"
            fi
          done <<< "$changed_files"

          echo "Required Scopes based on changed files: ${required_scopes[@]}"

          if [[ " ${pr_scopes[@]} " =~ " * " ]]; then
            echo "Wildcard scope '*' in PR title allows all changes."
            exit 0
          fi

          missing_scopes=()
          for req_scope in "${required_scopes[@]}"; do
            is_covered=false
            for pr_scope in "${pr_scopes[@]}"; do
              if [ "$req_scope" == "$pr_scope" ]; then
                is_covered=true
                break
              fi
            done
            if [ "$is_covered" == false ]; then
              missing_scopes+=("$req_scope")
            fi
          done

          if [ ${#missing_scopes[@]} -gt 0 ]; then
            echo "::error::PR title scopes do not cover all changed files. Missing scopes for: ${missing_scopes[@]}"
            # Prepare message for PR comment
            comment_body="**Scope Check Failed!** 🚨\n\nPR title scopes do not cover all changed files.\n\n"
            comment_body+="Missing required scopes in PR title: \`${missing_scopes[@]}\`\n\n"
            comment_body+="Please update your PR title to include these scopes. For example: \`type(${pr_scopes_str:+${pr_scopes_str},}${missing_scopes[@]}): your message\` or \`type(*): your message\` if a wildcard is appropriate.\n\n"
            comment_body+="<details><summary>Details</summary>\n"
            comment_body+="PR Title Scopes: \`${pr_scopes[@]}\`\n"
            comment_body+="Required Scopes from changed files: \`${required_scopes[@]}\`\n"
            comment_body+="Changed Files:\n"
            comment_body+="\`\`\`\n${changed_files}\n\`\`\`\n"
            comment_body+="</details>"

            echo "comment_body=$comment_body" >> $GITHUB_ENV
            exit 1
          else
            echo "PR title scopes are valid."
          fi
  comment_on_pr:
    if: failure() && needs.check_scope.outputs.outcome == 'failure'
    needs: check_scope
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
      - name: Comment on PR
        uses: actions/github-script@v6
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            const body = `${process.env.comment_body}`;
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: body
            });