public function checkOutNew($name, $parent = null, $upstream = null, $dir = null, $mustRun = false)
    {
        $args = ['checkout', '-b', $name];
        if ($parent !== null) {
            $args[] = $parent;
        } elseif ($upstream !== null) {
            $args[] = '--track';
            $args[] = $upstream;
        }

        return (bool) $this->execute($args, $dir, $mustRun, false);
    }