Made ldap_filter_params handling more robust

ldapalchemy/model.py

@@ -68,8 +68,8 @@ class ModelQuery:
 		return make_modelobjs(objs, self.model)
 
 	def filter_by(self, **kwargs):
-		filter_params = self.model.ldap_filter_params
-		filter_params += tuple((getattr(self.model, attr).name, value) for attr, value in kwargs.items())
+		filter_params = list(self.model.ldap_filter_params)
+		filter_params += [(getattr(self.model, attr).name, value) for attr, value in kwargs.items()]
 		session = self.model.ldap_mapper.session.ldap_session
 		objs = session.filter(self.model.ldap_search_base, filter_params)
 		return make_modelobjs(objs, self.model)

ldapalchemy/relationship.py

@@ -87,7 +87,7 @@ class BackreferenceSet(MutableSet):
 	def __get(self):
 		if self.__ldap_object.session is None:
 			return set()
-		filter_params = self.__srcmodel.ldap_filter_params + ((self.__name, self.__ldap_object.dn),)
+		filter_params = list(self.__srcmodel.ldap_filter_params) + [(self.__name, self.__ldap_object.dn)]
 		objs = self.__ldap_object.session.filter(self.__srcmodel.ldap_search_base, filter_params)
 		return set(make_modelobjs(objs, self.__srcmodel))