ENGCOM-2128: Wishlist update item issue #16372

Author: VladimirZaets

app/code/Magento/Wishlist/Model/Wishlist.php

@@ -3,6 +3,7 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+
 namespace Magento\Wishlist\Model;
 
 use Magento\Catalog\Api\ProductRepositoryInterface;
@@ -215,9 +216,11 @@ public function loadByCustomerId($customerId, $create = false)
     public function getName()
     {
         $name = $this->_getData('name');
-        if (!strlen($name)) {
+
+        if ($name === null || !strlen($name)) {
             return $this->_wishlistData->getDefaultWishlistName();
         }
+
         return $name;
     }
 
@@ -637,6 +640,7 @@ public function updateItem($itemId, $buyRequest, $params = null)
         $item = null;
         if ($itemId instanceof Item) {
             $item = $itemId;
+            $itemId = $item->getId();
         } else {
             $item = $this->getItem((int)$itemId);
         }