private function addIndentationToMessages($messages)
    {
        if (is_array($messages)) {
            array_walk(
                $messages,
                function ($message) {
                    return $this->indentation . $message;
                }
            );
            return $messages;
        } else {
            $messages = $this->indentation . $messages;
            return $messages;
        }
    }