fix access array offset which doesn't exist and check if returned val…

…ue is null

This check is used since default array is empty if user folder was not found

Signed-off-by: Jan Messer <[email protected]>

lib/FilesHooks.php

@@ -396,7 +396,10 @@ protected function fileMoving($oldPath, $newPath) {
 		}
 		$accessList = $this->getUserPathsFromPath($parentPath, $parentOwner);
 		$affectedUsers = $accessList['users'];
-		$oldUsers = $this->oldAccessList['users'];
+		$oldUsers = [];
+		if (isset($this->oldAccessList['users'])) {
+			$oldUsers = $this->oldAccessList['users'];
+		}
 
 		// file can be shared using GroupFolders, including ACL check
 		if ($this->config->getSystemValueBool('activity_use_cached_mountpoints', false)) {
@@ -416,7 +419,10 @@ protected function fileMoving($oldPath, $newPath) {
 		$moveUsers = array_intersect($beforeUsers, $afterUsers);
 		$this->generateMoveActivities($moveUsers, $oldUsers, $affectedUsers, $fileId, $oldFileName, $parentId, $fileName);
 
-		$beforeRemotes = $this->oldAccessList['remotes'];
+		$beforeRemotes = [];
+		if (isset($this->oldAccessList['users'])) {
+			$beforeRemotes = $this->oldAccessList['remotes'];
+		}
 		$afterRemotes = $accessList['remotes'];
 
 		$addRemotes = $deleteRemotes = $moveRemotes = [];