Merge remote-tracking branch 'origin/AC-13311' into spartans_pr_27102025

Author: glo60612

app/code/Magento/Catalog/Model/ProductLink/Repository.php

@@ -139,7 +139,7 @@ public function save(\Magento\Catalog\Api\Data\ProductLinkInterface $entity)
                 . 'Please ensure the parent product SKU is provided and try again.'
             ));
         }
-        if (!$entity->getLinkedProductSku()) {
+        if ($entity->getLinkedProductSku() === null || $entity->getLinkedProductSku() === '') {
             throw new CouldNotSaveException(__('The linked product SKU is invalid. Verify the data and try again.'));
         }
         $linkedProduct = $this->productRepository->get($entity->getLinkedProductSku());

app/code/Magento/Catalog/Test/Unit/Model/ProductLink/RepositoryTest.php

@@ -298,4 +298,16 @@ public function testDeleteWithNoSuchEntityException()
 
         $this->model->delete($entityMock);
     }
+
+    public function testSaveWithNullLinkedProductSku()
+    {
+        $this->expectException('Magento\Framework\Exception\CouldNotSaveException');
+        $this->expectExceptionMessage('The linked product SKU is invalid. Verify the data and try again.');
+
+        $entityMock = $this->createMock(\Magento\Catalog\Model\ProductLink\Link::class);
+        $entityMock->expects($this->any())->method('getSku')->willReturn('sku1');
+        $entityMock->expects($this->any())->method('getLinkedProductSku')->willReturn(null);
+
+        $this->model->save($entityMock);
+    }
 }

dev/tests/integration/testsuite/Magento/Catalog/Model/ProductLink/RepositorySaveTest.php

@@ -0,0 +1,59 @@
+<?php
+/**
+ * Copyright 2025 Adobe
+ * All Rights Reserved.
+ */
+declare(strict_types=1);
+
+namespace Magento\Catalog\Model\ProductLink;
+
+use Magento\Catalog\Api\ProductLinkRepositoryInterface;
+use Magento\Catalog\Model\ProductLink\Link;
+use Magento\Framework\Exception\CouldNotSaveException;
+use Magento\TestFramework\Helper\Bootstrap;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @magentoAppIsolation enabled
+ */
+class RepositorySaveTest extends TestCase
+{
+    /**
+     * @var ProductLinkRepositoryInterface
+     */
+    private $repository;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        $this->repository = Bootstrap::getObjectManager()->get(ProductLinkRepositoryInterface::class);
+    }
+
+    public function testSaveWithNullLinkedProductSku(): void
+    {
+        $this->expectException(CouldNotSaveException::class);
+        $this->expectExceptionMessage('The linked product SKU is invalid. Verify the data and try again.');
+
+        $objectManager = Bootstrap::getObjectManager();
+        /** @var Link $link */
+        $link = $objectManager->create(Link::class);
+        $link->setSku('sku1');
+        $link->setLinkedProductSku(null);
+
+        $this->repository->save($link);
+    }
+
+    public function testSaveWithEmptyLinkedProductSku(): void
+    {
+        $this->expectException(CouldNotSaveException::class);
+        $this->expectExceptionMessage('The linked product SKU is invalid. Verify the data and try again.');
+
+        $objectManager = Bootstrap::getObjectManager();
+        /** @var Link $link */
+        $link = $objectManager->create(Link::class);
+        $link->setSku('sku1');
+        $link->setLinkedProductSku('');
+
+        $this->repository->save($link);
+    }
+}