protected function globFiles(
        /*# string */ $group,
        /*# string */ $environment
    )/*# : array */ {
        $files = [];
        $group = '' === $group ? '*' : $group;
        foreach ($this->getSearchDirs($environment) as $dir) {
            $file  = $dir . $group . '.' . $this->file_type;
            $files = array_merge($files, glob($file));
        }
        return $files;
    }