Codeception\TestCase\WPTestCase::scandir PHP Method

    function scandir($dir)
    {
        foreach (scandir($dir) as $path) {
            if (0 !== strpos($path, '.') && is_dir($dir . '/' . $path)) {
                $this->matched_dirs[] = $dir . '/' . $path;
                $this->scandir($dir . '/' . $path);
            }
        }
    }