FIX: null cases & method name

common/Define/Model/DateTime.php

@@ -4,7 +4,7 @@ namespace ProVM\Common\Define\Model;
 use Carbon\Carbon;
 
 trait DateTime {
-  public function date(\DateTime $date_time) {
+  public function dateTime(\DateTime $date_time = null) {
     if ($date_time === null) {
       return Carbon::parse($this->date_time);
     }