public static function setUpBeforeClass()
{
self::$rootDir = __DIR__ . '/../../tmp';
$fs = new Filesystem();
$fs->mkdir(self::$rootDir);
$fs->mkdir(self::$rootDir . '/assets');
$fs->mkdir(self::$rootDir . '/assets/images');
foreach ([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 'a', 'b', 'c', 'd', 'e', 'f'] as $subdir) {
$fs->mkdir(self::$rootDir . '/assets/images/' . $subdir);
}
$fs->mkdir(self::$rootDir . '/system');
$fs->mkdir(self::$rootDir . '/system/tmp');
}