Add empty object_list support to the 'filter_objects_by_access' manager method

apps/acls/models.py

@@ -274,6 +274,14 @@ class AccessEntryManager(models.Manager):
             if actor.is_superuser or actor.is_staff:
                 return object_list
         
+        try:
+            if object_list.count() == 0:
+                return object_list
+        except TypeError:
+            # object_list is not a queryset
+            if len(object_list) == 0:
+                return object_list
+        
         try:
             # Try to process as a QuerySet
             qs = object_list.filter(pk__in=[obj.pk for obj in self.get_allowed_class_objects(permission, actor, object_list[0])])