From b51d60dbdfcfd6fad5fabe540f04365886d35c58 Mon Sep 17 00:00:00 2001
From: Matthias Schmidt <gravatronics@live.com>
Date: Wed, 4 Mar 2015 20:00:10 +0100
Subject: [PATCH] Improve UserGroupAssignmentHandler::checkUsers()

---
 .../UserGroupAssignmentHandler.class.php           | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/wcfsetup/install/files/lib/system/user/group/assignment/UserGroupAssignmentHandler.class.php b/wcfsetup/install/files/lib/system/user/group/assignment/UserGroupAssignmentHandler.class.php
index e57889a0c1..e1754463f0 100644
--- a/wcfsetup/install/files/lib/system/user/group/assignment/UserGroupAssignmentHandler.class.php
+++ b/wcfsetup/install/files/lib/system/user/group/assignment/UserGroupAssignmentHandler.class.php
@@ -64,12 +64,14 @@ class UserGroupAssignmentHandler extends SingletonFactory {
 				}
 			}
 			
-			$userAction = new UserAction(array($user), 'addToGroups', array(
-				'addDefaultGroups' => false,
-				'deleteOldGroups' => false,
-				'groups' => $newGroupIDs
-			));
-			$userAction->executeAction();
+			if (!empty($newGroupIDs)) {
+				$userAction = new UserAction(array($user), 'addToGroups', array(
+					'addDefaultGroups' => false,
+					'deleteOldGroups' => false,
+					'groups' => $newGroupIDs
+				));
+				$userAction->executeAction();
+			}
 		}
 	}
 	
-- 
2.20.1