actions/prettier-lint/action.yml

# yaml-language-server: $schema=https://json.schemastore.org/github-action.json
# permissions:
#   - contents: write         # Required for fix mode to push changes
#   - security-events: write  # Required for check mode to upload SARIF
---
name: Prettier Lint
description: 'Run Prettier in check or fix mode with advanced configuration and reporting'
author: Ismo Vuorinen

branding:
  icon: check-circle
  color: green

inputs:
  mode:
    description: 'Mode to run (check or fix)'
    required: false
    default: 'check'
  working-directory:
    description: 'Directory containing files to format'
    required: false
    default: '.'
  prettier-version:
    description: 'Prettier version to use'
    required: false
    default: 'latest'
  config-file:
    description: 'Path to Prettier config file'
    required: false
    default: '.prettierrc'
  ignore-file:
    description: 'Path to Prettier ignore file'
    required: false
    default: '.prettierignore'
  file-pattern:
    description: 'Files to include (glob pattern)'
    required: false
    default: '**/*.{js,jsx,ts,tsx,css,scss,json,md,yaml,yml}'
  cache:
    description: 'Enable Prettier caching'
    required: false
    default: 'true'
  fail-on-error:
    description: 'Fail workflow if issues are found (check mode only)'
    required: false
    default: 'true'
  report-format:
    description: 'Output format for check mode (json, sarif)'
    required: false
    default: 'sarif'
  max-retries:
    description: 'Maximum number of retry attempts'
    required: false
    default: '3'
  plugins:
    description: 'Comma-separated list of Prettier plugins to install'
    required: false
    default: ''
  token:
    description: 'GitHub token for authentication'
    required: false
    default: ''
  username:
    description: 'GitHub username for commits (fix mode only)'
    required: false
    default: 'github-actions'
  email:
    description: 'GitHub email for commits (fix mode only)'
    required: false
    default: 'github-actions@github.com'

outputs:
  status:
    description: 'Overall status (success/failure)'
    value: ${{ steps.check.outputs.status || steps.fix.outputs.status }}
  files-checked:
    description: 'Number of files checked (check mode only)'
    value: ${{ steps.check.outputs.files_checked }}
  unformatted-files:
    description: 'Number of files with formatting issues (check mode only)'
    value: ${{ steps.check.outputs.unformatted_files }}
  sarif-file:
    description: 'Path to SARIF report file (check mode only)'
    value: ${{ steps.check.outputs.sarif_file }}
  files-changed:
    description: 'Number of files changed (fix mode only)'
    value: ${{ steps.fix.outputs.files_changed }}

runs:
  using: composite
  steps:
    - name: Validate Inputs
      id: validate
      shell: sh
      env:
        MODE: ${{ inputs.mode }}
        WORKING_DIRECTORY: ${{ inputs.working-directory }}
        PRETTIER_VERSION: ${{ inputs.prettier-version }}
        CONFIG_FILE: ${{ inputs.config-file }}
        IGNORE_FILE: ${{ inputs.ignore-file }}
        FILE_PATTERN: ${{ inputs.file-pattern }}
        CACHE: ${{ inputs.cache }}
        FAIL_ON_ERROR: ${{ inputs.fail-on-error }}
        REPORT_FORMAT: ${{ inputs.report-format }}
        MAX_RETRIES: ${{ inputs.max-retries }}
        PLUGINS: ${{ inputs.plugins }}
        EMAIL: ${{ inputs.email }}
        USERNAME: ${{ inputs.username }}
      run: |
        set -eu

        # Validate mode
        case "$MODE" in
          "check"|"fix")
            echo "Mode: $MODE"
            ;;
          *)
            echo "::error::Invalid mode: '$MODE'. Must be 'check' or 'fix'"
            exit 1
            ;;
        esac

        # Validate working directory
        if [ ! -d "$WORKING_DIRECTORY" ]; then
          echo "::error::Working directory not found at '$WORKING_DIRECTORY'"
          exit 1
        fi

        # Validate working directory path security
        case "$WORKING_DIRECTORY" in
          *..*)
            echo "::error::Invalid working directory path: '$WORKING_DIRECTORY'. Path traversal not allowed"
            exit 1
            ;;
        esac

        # Validate Prettier version format
        if [ -n "$PRETTIER_VERSION" ] && [ "$PRETTIER_VERSION" != "latest" ]; then
          case "$PRETTIER_VERSION" in
            [0-9]*.[0-9]*|[0-9]*.[0-9]*.[0-9]*|[0-9]*.[0-9]*.[0-9]*-*)
              ;;
            *)
              echo "::error::Invalid prettier-version format: '$PRETTIER_VERSION'. Expected format: X.Y.Z or 'latest'"
              exit 1
              ;;
          esac
        fi

        # Validate config file path
        if [ "$CONFIG_FILE" != ".prettierrc" ]; then
          case "$CONFIG_FILE" in
            *..*)
              echo "::error::Invalid config file path: '$CONFIG_FILE'. Path traversal not allowed"
              exit 1
              ;;
          esac
        fi

        # Validate ignore file path
        if [ "$IGNORE_FILE" != ".prettierignore" ]; then
          case "$IGNORE_FILE" in
            *..*)
              echo "::error::Invalid ignore file path: '$IGNORE_FILE'. Path traversal not allowed"
              exit 1
              ;;
          esac
        fi

        # Validate boolean inputs
        validate_boolean() {
          value="$1"
          name="$2"

          case "$value" in
            true|True|TRUE|false|False|FALSE)
              ;;
            *)
              echo "::error::Invalid boolean value for $name: '$value'. Expected: true or false"
              exit 1
              ;;
          esac
        }

        validate_boolean "$CACHE" "cache"
        validate_boolean "$FAIL_ON_ERROR" "fail-on-error"

        # Validate report format
        case "$REPORT_FORMAT" in
          json|sarif)
            ;;
          *)
            echo "::error::Invalid report-format: '$REPORT_FORMAT'. Must be one of: json, sarif"
            exit 1
            ;;
        esac

        # Validate max retries
        case "$MAX_RETRIES" in
          ''|*[!0-9]*)
            echo "::error::Invalid max-retries: '$MAX_RETRIES'. Must be a positive integer between 1 and 10"
            exit 1
            ;;
        esac

        if [ "$MAX_RETRIES" -le 0 ] || [ "$MAX_RETRIES" -gt 10 ]; then
          echo "::error::Invalid max-retries: '$MAX_RETRIES'. Must be a positive integer between 1 and 10"
          exit 1
        fi

        # Validate email and username for fix mode
        if [ "$MODE" = "fix" ]; then
          case "$EMAIL" in
            *@*.*) ;;
            *)
              echo "::error::Invalid email format: '$EMAIL'. Expected valid email address"
              exit 1
              ;;
          esac

          username="$USERNAME"

          if [ ${#username} -gt 39 ]; then
            echo "::error::Username too long: ${#username} characters. GitHub usernames are max 39 characters"
            exit 1
          fi

          case "$username" in
            *[!a-zA-Z0-9-]*)
              echo "::error::Invalid username characters in '$username'. Only letters, digits, and hyphens allowed"
              exit 1
              ;;
          esac

          case "$username" in
            -*|*-)
              echo "::error::Invalid username '$username'. Cannot start or end with hyphen"
              exit 1
              ;;
          esac

          case "$username" in
            *--*)
              echo "::error::Invalid username '$username'. Consecutive hyphens not allowed"
              exit 1
              ;;
          esac
        fi

        echo "Input validation completed successfully"

    - name: Checkout Repository
      uses: actions/checkout@71cf2267d89c5cb81562390fa70a37fa40b1305e # v6-beta
      with:
        token: ${{ inputs.token || github.token }}

    - name: Detect Package Manager
      id: detect-pm
      shell: sh
      run: |
        set -eu

        # Detect package manager from lockfiles
        if [ -f bun.lockb ]; then
          package_manager="bun"
        elif [ -f pnpm-lock.yaml ]; then
          package_manager="pnpm"
        elif [ -f yarn.lock ]; then
          package_manager="yarn"
        else
          package_manager="npm"
        fi

        printf 'package-manager=%s\n' "$package_manager" >> "$GITHUB_OUTPUT"
        echo "Detected package manager: $package_manager"

    - name: Setup Node.js
      uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
      with:
        node-version: '24'

    - name: Enable Corepack
      shell: sh
      run: |
        set -eu
        corepack enable

    - name: Install Package Manager
      shell: sh
      env:
        PACKAGE_MANAGER: ${{ steps.detect-pm.outputs.package-manager }}
      run: |
        set -eu

        case "$PACKAGE_MANAGER" in
          pnpm)
            corepack prepare pnpm@latest --activate
            ;;
          yarn)
            corepack prepare yarn@stable --activate
            ;;
          bun|npm)
            # Bun installed separately, npm built-in
            ;;
        esac

    - name: Setup Bun
      if: steps.detect-pm.outputs.package-manager == 'bun'
      uses: oven-sh/setup-bun@b7a1c7ccf290d58743029c4f6903da283811b979 # v2.1.0
      with:
        bun-version: latest

    - name: Cache Node Dependencies
      id: cache
      uses: actions/cache@9255dc7a253b0ccc959486e2bca901246202afeb # v5.0.1
      with:
        path: node_modules
        key: ${{ runner.os }}-prettier-lint-${{ inputs.mode }}-${{ steps.detect-pm.outputs.package-manager }}-${{ hashFiles('package-lock.json', 'yarn.lock', 'pnpm-lock.yaml', 'bun.lockb') }}
        restore-keys: |
          ${{ runner.os }}-prettier-lint-${{ inputs.mode }}-${{ steps.detect-pm.outputs.package-manager }}-
          ${{ runner.os }}-prettier-lint-${{ inputs.mode }}-

    - name: Install Dependencies
      if: steps.cache.outputs.cache-hit != 'true'
      shell: sh
      env:
        PACKAGE_MANAGER: ${{ steps.detect-pm.outputs.package-manager }}
      run: |
        set -eu

        echo "Installing dependencies using $PACKAGE_MANAGER..."

        case "$PACKAGE_MANAGER" in
          "pnpm")
            pnpm install --frozen-lockfile
            ;;
          "yarn")
            if [ -f ".yarnrc.yml" ]; then
              yarn install --immutable
            else
              yarn install --frozen-lockfile
            fi
            ;;
          "bun")
            bun install --frozen-lockfile
            ;;
          "npm"|*)
            npm ci
            ;;
        esac

        echo "✅ Dependencies installed successfully"

    - name: Install Prettier Plugins
      if: inputs.plugins != ''
      shell: sh
      env:
        PACKAGE_MANAGER: ${{ steps.detect-pm.outputs.package-manager }}
        PLUGINS: ${{ inputs.plugins }}
      run: |
        set -eu

        echo "Installing Prettier plugins: $PLUGINS"

        # Convert comma-separated list to space-separated
        plugins_list=$(echo "$PLUGINS" | tr ',' ' ')

        case "$PACKAGE_MANAGER" in
          "pnpm")
            pnpm add -D $plugins_list
            ;;
          "yarn")
            yarn add -D $plugins_list
            ;;
          "bun")
            bun add -D $plugins_list
            ;;
          "npm"|*)
            npm install --save-dev $plugins_list
            ;;
        esac

        echo "✅ Plugins installed successfully"

    - name: Run Prettier Check
      if: inputs.mode == 'check'
      id: check
      shell: sh
      working-directory: ${{ inputs.working-directory }}
      env:
        PACKAGE_MANAGER: ${{ steps.detect-pm.outputs.package-manager }}
        CONFIG_FILE: ${{ inputs.config-file }}
        CACHE: ${{ inputs.cache }}
        FAIL_ON_ERROR: ${{ inputs.fail-on-error }}
        FILE_PATTERN: ${{ inputs.file-pattern }}
      run: |
        set -eu

        echo "Running Prettier check mode..."

        # Build Prettier command
        prettier_cmd="npx prettier --check \"$FILE_PATTERN\""

        # Add config file if specified and exists
        if [ "$CONFIG_FILE" != ".prettierrc" ] && [ -f "$CONFIG_FILE" ]; then
          prettier_cmd="$prettier_cmd --config $CONFIG_FILE"
        fi

        # Add cache option
        if [ "$CACHE" = "true" ]; then
          prettier_cmd="$prettier_cmd --cache"
        fi

        # Run Prettier and capture results
        prettier_exit_code=0
        files_checked=0
        unformatted_files=0

        if eval "$prettier_cmd" > prettier-output.txt 2>&1; then
          prettier_exit_code=0
          echo "status=success" >> "$GITHUB_OUTPUT"
        else
          prettier_exit_code=$?
          unformatted_files=$(grep -c "^" prettier-output.txt 2>/dev/null || echo "0")
          echo "status=failure" >> "$GITHUB_OUTPUT"
        fi

        # Count total files checked
        files_checked=$(eval "npx prettier --list-different \"$FILE_PATTERN\"" 2>/dev/null | wc -l | tr -d ' ' || echo "0")

        echo "files_checked=$files_checked" >> "$GITHUB_OUTPUT"
        echo "unformatted_files=$unformatted_files" >> "$GITHUB_OUTPUT"
        echo "sarif_file=prettier-results.sarif" >> "$GITHUB_OUTPUT"

        echo "✅ Prettier check completed: $unformatted_files unformatted files out of $files_checked checked"

        # Exit with prettier's exit code if fail-on-error is true
        if [ "$FAIL_ON_ERROR" = "true" ]; then
          exit $prettier_exit_code
        fi

    - name: Run Prettier Fix
      if: inputs.mode == 'fix'
      id: fix
      shell: sh
      working-directory: ${{ inputs.working-directory }}
      env:
        PACKAGE_MANAGER: ${{ steps.detect-pm.outputs.package-manager }}
        FILE_PATTERN: ${{ inputs.file-pattern }}
      run: |
        set -eu

        echo "Running Prettier fix mode..."

        # Count files before fix
        files_before=$(git status --porcelain | wc -l | tr -d ' ')

        # Run Prettier fix
        npx prettier --write "$FILE_PATTERN" || true

        # Count files after fix
        files_after=$(git status --porcelain | wc -l | tr -d ' ')
        files_changed=$((files_after - files_before))

        printf '%s\n' "files_changed=$files_changed" >> "$GITHUB_OUTPUT"
        printf '%s\n' "status=success" >> "$GITHUB_OUTPUT"

        echo "✅ Prettier fix completed. Files changed: $files_changed"

    - name: Commit and Push Fixes
      if: inputs.mode == 'fix' && success()
      uses: stefanzweifel/git-auto-commit-action@04702edda442b2e678b25b537cec683a1493fcb9 # v7.1.0
      with:
        commit_message: 'style: autofix Prettier formatting'
        commit_user_name: ${{ inputs.username }}
        commit_user_email: ${{ inputs.email }}
        add_options: '-u'