protected function scanTags()
    {
        $line = $this->getTrimmedLine();
        if (!isset($line[0]) || '@' !== $line[0]) {
            return null;
        }

        $token = $this->takeToken('Tag');
        $tags = explode('@', mb_substr($line, 1, mb_strlen($line, 'utf8') - 1, 'utf8'));
        $tags = array_map('trim', $tags);
        $token['tags'] = $tags;

        $this->consumeLine();

        return $token;
    }