code: function attacher (retext, options) {
    return function transformer (cst, file, next) {
      var textlint = new TextLintEngine(options)
      var result = textlint.executeOnText(toString(cst))
  
      if (result) {
        var messages = result[0].messages
  
        for (var index = 0; index < messages.length; index++) {
          var msg = messages[index]
          var msgText = '"' + msg.ruleId + '" ' + msg.message
  
          if (msg.severity === 1) {
            file.warn(msgText, {line: msg.line, column: msg.column})
          } else if (msg.severity === 2) {
            file.fail(msgText, {line: msg.line, column: msg.column})
          }
        }
      }
  
      next()
    }
  }
docs: Attacher.
  
  @param {Retext} retext
  @param {Object} options
  @returns {Function} - `transformer`.