public function up($to = null)
{
// sorted migration files
$files = $this->files();
if (is_null($to)) {
$to = end(array_keys($files));
}
// run migrations
foreach ($files as $num => $item) {
// upto
if ($num > $to) {
break;
}
// starting from
if ($num < $this->current) {
continue;
}
// run
require $item['path'];
$m = new $item['class']();
$m->up();
}
return $num;
}