+               //Get the unique roles list by id
+               return array_unique(array_reduce(
+                       //Cast groups as array
+                       $this->groups->toArray(),
+                       //Reduce to an array of id => group tuples
+                       function ($array, $group) {
+                               $array[$group->getId()] = $group->getRole();
+                               return $array;
+                       },
+                       //Init with empty array
+                       //XXX: on registration, add each group present in rapsys_user.default.group array to user
+                       //XXX: see vendor/rapsys/userbundle/Controller/DefaultController.php +450
+                       []
+               ));