MC-40070: Create automated test for: "Try to save product with string type qty value"

Author: ysapiga

dev/tests/integration/testsuite/Magento/Catalog/Model/Product/Attribute/Backend/StockTest.php

@@ -0,0 +1,62 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\Catalog\Model\Product\Attribute\Backend;
+
+use Magento\Catalog\Api\Data\ProductInterfaceFactory;
+use Magento\Catalog\Model\Product;
+use Magento\Eav\Model\Config;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Framework\ObjectManagerInterface;
+use Magento\TestFramework\Helper\Bootstrap;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Test class for backend stock attribute model.
+ *
+ * @see \Magento\Catalog\Model\Product\Attribute\Backend\Stock
+ *
+ * @magentoAppArea adminhtml
+ */
+class StockTest extends TestCase
+{
+    /** @var ObjectManagerInterface */
+    private $objectManager;
+
+    /** @var ProductInterfaceFactory */
+    private $productFactory;
+
+    /** @var Stock */
+    private $model;
+
+    /**
+     * @inheritdoc
+     */
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->objectManager = Bootstrap::getObjectManager();
+        $this->productFactory = $this->objectManager->get(ProductInterfaceFactory::class);
+        $this->model = $this->objectManager->get(Stock::class);
+        $this->model->setAttribute(
+            $this->objectManager->get(Config::class)->getAttribute(Product::ENTITY, 'quantity_and_stock_status')
+        );
+    }
+
+    /**
+     * @return void
+     */
+    public function testValidate(): void
+    {
+        $this->expectException(LocalizedException::class);
+        $this->expectErrorMessage((string)__('Please enter a valid number in this field.'));
+        $product = $this->productFactory->create();
+        $product->setQuantityAndStockStatus(['qty' => 'string']);
+        $this->model->validate($product);
+    }
+}