fix: [MINT-4753] add plugin to enrich configurable products with sku info if magento inventory management is disabled (#215)

* fix: [MINT-4753] add plugin to enrich configurable products with sku info if magento inventory management is disabled

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* fix existing unit test failures

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* attemt lint:php fix for CI

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* fix: use correct 'sku' property instead of 'skus' in non-swatch configurable products

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---------

Co-authored-by: magento-bot <[email protected]>

Author: milesmcleod

Plugin/ConfigurableProduct/Block/Product/View/Type/Configurable/AddSkuInfo.php

@@ -0,0 +1,95 @@
+<?php
+/*
+ * Copyright Extend (c) 2025. All rights reserved.
+ * See Extend-COPYING.txt for license details.
+ */
+
+namespace Extend\Integration\Plugin\ConfigurableProduct\Block\Product\View\Type\Configurable;
+
+use Magento\ConfigurableProduct\Block\Product\View\Type\Configurable as ConfigurableBlock;
+use Magento\Framework\Serialize\Serializer\Json;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Plugin to add SKU information to configurable product JSON config
+ *
+ * This plugin ensures that the 'sku' node is present in spConfig regardless of
+ * whether Magento Inventory Management (MSI) modules are enabled. The Extend
+ * integration relies on this data to display warranty offers for configurable products.
+ *
+ * Background:
+ * Magento's InventoryConfigurableProductFrontendUi module provides a similar plugin
+ * (AddAdditionalInfo) that adds SKU data, but only when MSI is enabled. This plugin
+ * provides a fallback to ensure Extend functionality works even when MSI is disabled.
+ */
+class AddSkuInfo
+{
+    /**
+     * @var Json
+     */
+    private $jsonSerializer;
+
+    /**
+     * @var LoggerInterface
+     */
+    private $logger;
+
+    /**
+     * @param Json $jsonSerializer
+     * @param LoggerInterface $logger
+     */
+    public function __construct(
+        Json $jsonSerializer,
+        LoggerInterface $logger
+    ) {
+        $this->jsonSerializer = $jsonSerializer;
+        $this->logger = $logger;
+    }
+
+    /**
+     * Add SKU information to configurable product JSON config
+     *
+     * This plugin runs after getJsonConfig() and adds a 'sku' array mapping
+     * product IDs to SKUs if it's not already present (from MSI).
+     *
+     * @param ConfigurableBlock $subject
+     * @param string $result
+     * @return string
+     */
+    public function afterGetJsonConfig(ConfigurableBlock $subject, string $result): string
+    {
+        try {
+            $jsonConfig = $this->jsonSerializer->unserialize($result);
+
+            // Only add SKU data if it's not already present (avoid duplicate work if MSI is enabled)
+            if (!isset($jsonConfig['sku']) || empty($jsonConfig['sku'])) {
+                $jsonConfig['sku'] = $this->getProductVariationsSku($subject);
+            }
+
+            return $this->jsonSerializer->serialize($jsonConfig);
+        } catch (\Exception $e) {
+            // Log error but return original result to avoid breaking the page
+            $this->logger->error(
+                'Extend Integration: Error adding SKU info to configurable product config',
+                ['exception' => $e->getMessage()]
+            );
+            return $result;
+        }
+    }
+
+    /**
+     * Get SKU for each product variation
+     *
+     * @param ConfigurableBlock $subject
+     * @return array Array mapping product IDs to SKUs
+     */
+    private function getProductVariationsSku(ConfigurableBlock $subject): array
+    {
+        $skus = [];
+        foreach ($subject->getAllowProducts() as $product) {
+            $skus[$product->getId()] = $product->getSku();
+        }
+
+        return $skus;
+    }
+}

Test/Unit/Controller/Minicart/CategoriesTest.php

@@ -9,11 +9,13 @@
 use PHPUnit\Framework\TestCase;
 use Magento\Catalog\Api\Data\CategoryInterface;
 use Magento\Catalog\Api\CategoryRepositoryInterface;
+use Magento\Catalog\Api\ProductRepositoryInterface;
 use Magento\Checkout\Model\Session as CheckoutSession;
 use Magento\Catalog\Model\Product;
 use Magento\Quote\Model\Quote;
 use Magento\Quote\Model\Quote\Item;
 use Magento\Framework\App\Action\Context;
+use Magento\Framework\App\RequestInterface;
 use Magento\Framework\Controller\Result\Json;
 use Magento\Framework\Controller\Result\JsonFactory;
 use Extend\Integration\Controller\Minicart\Categories;
@@ -30,6 +32,11 @@ class CategoriesTest extends TestCase
      */
     protected $categoryRepository;
 
+    /**
+     * @var ProductRepositoryInterface
+     */
+    protected $productRepository;
+
     /**
      * @var JsonFactory
      */
@@ -42,17 +49,26 @@ class CategoriesTest extends TestCase
 
     protected function setUp(): void
     {
-        $context = $this->createStub(Context::class);
+        // Create a mock request that returns null for getParam (simulating no product_ids parameter)
+        $request = $this->createMock(RequestInterface::class);
+        $request->method('getParam')->willReturn(null);
+
+        // Create a mock context that provides the request
+        $context = $this->createMock(Context::class);
+        $context->method('getRequest')->willReturn($request);
+
         $this->resultJsonFactory = $this->createStub(JsonFactory::class);
         $this->checkoutSession = $this->createStub(CheckoutSession::class);
         $this->categoryRepository = $this->createStub(CategoryRepositoryInterface::class);
+        $this->productRepository = $this->createStub(ProductRepositoryInterface::class);
 
         $this->categories = new Categories(
-          $context,
-          $this->resultJsonFactory,
-          $this->checkoutSession,
-          $this->categoryRepository
-      );
+            $context,
+            $this->resultJsonFactory,
+            $this->checkoutSession,
+            $this->categoryRepository,
+            $this->productRepository
+        );
     }
 
     public function testGetCategories()
@@ -123,7 +139,8 @@ public function testGetCategoriesWhereItemHasNoCategories()
         $this->assertEquals([], $this->categories->execute());
     }
 
-    public function testGetCategoriesWhereItemProductDoesNotExist() {
+    public function testGetCategoriesWhereItemProductDoesNotExist()
+    {
         $quoteItemMock = $this->getMockBuilder(Item::class)
           ->disableOriginalConstructor()
           ->onlyMethods(['getProduct'])