Pagekit\Installer\SelfUpdater::isWritable PHP Метод

    protected function isWritable($fileList, $path)
    {
        $notWritable = [];
        if (!file_exists($path)) {
            throw new \RuntimeException(sprintf('"%s" not writable', $path));
        }
        foreach ($fileList as $file) {
            $file = $path . '/' . $file;
            while (!file_exists($file)) {
                $file = dirname($file);
            }
            if (!is_writable($file)) {
                $notWritable[] = $file;
            }
        }
        return $notWritable ?: true;
    }