MC-39878: Invoice for an order that contains only one configurable product is not generated correctly

Author: mastiuhin-olexandr

app/code/Magento/Sales/Model/Order/Invoice.php

@@ -679,6 +679,11 @@ public function register()
     public function isLast()
     {
         foreach ($this->getAllItems() as $item) {
+            $orderItem = $item->getOrderItem();
+            if ($orderItem->isDummy()) {
+                continue;
+            }
+
             if (!$item->isLast()) {
                 return false;
             }

dev/tests/integration/testsuite/Magento/Sales/Model/Order/InvoiceTest.php

@@ -3,20 +3,57 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
+
 namespace Magento\Sales\Model\Order;
 
-class InvoiceTest extends \PHPUnit\Framework\TestCase
+use PHPUnit\Framework\TestCase;
+use Magento\TestFramework\Helper\Bootstrap;
+use Magento\Sales\Model\ResourceModel\Order\Collection as OrderCollection;
+use Magento\Sales\Api\InvoiceManagementInterface;
+use Magento\Sales\Api\OrderRepositoryInterface;
+use Magento\Framework\Api\SearchCriteriaBuilder;
+
+/**
+ * Invoice model test.
+ */
+class InvoiceTest extends TestCase
 {
     /**
-     * @var \Magento\Sales\Model\ResourceModel\Order\Collection
+     * @var \Magento\Framework\ObjectManagerInterface
+     */
+    private $objectManager;
+
+    /**
+     * @var OrderCollection
+     */
+    private $collection;
+
+    /**
+     * @var InvoiceManagementInterface
+     */
+    private $invoiceManagement;
+
+    /**
+     * @var OrderRepositoryInterface
+     */
+    private $orderRepository;
+
+    /**
+     * @var SearchCriteriaBuilder
      */
-    private $_collection;
+    private $searchCriteriaBuilder;
 
+    /**
+     * @inheritDoc
+     */
     protected function setUp(): void
     {
-        $this->_collection = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create(
-            \Magento\Sales\Model\ResourceModel\Order\Collection::class
-        );
+        $this->objectManager = Bootstrap::getObjectManager();
+        $this->collection = $this->objectManager->create(OrderCollection::class);
+        $this->invoiceManagement = $this->objectManager->get(InvoiceManagementInterface::class);
+        $this->orderRepository = $this->objectManager->get(OrderRepositoryInterface::class);
+        $this->searchCriteriaBuilder = $this->objectManager->get(SearchCriteriaBuilder::class);
     }
 
     /**
@@ -27,9 +64,27 @@ public function testOrderTotalItemCount()
         $expectedResult = [['total_item_count' => 1]];
         $actualResult = [];
         /** @var \Magento\Sales\Model\Order $order */
-        foreach ($this->_collection->getItems() as $order) {
+        foreach ($this->collection->getItems() as $order) {
             $actualResult[] = ['total_item_count' => $order->getData('total_item_count')];
         }
         $this->assertEquals($expectedResult, $actualResult);
     }
+
+    /**
+     * Test order with exactly one configurable.
+     *
+     * @return void
+     * @magentoDataFixture Magento/Sales/_files/order_configurable_product.php
+     */
+    public function testLastInvoiceWithConfigurable(): void
+    {
+        $searchCriteria = $this->searchCriteriaBuilder->addFilter('increment_id', '100000001')
+            ->create();
+        $orders = $this->orderRepository->getList($searchCriteria);
+        $orders = $orders->getItems();
+        $order = array_shift($orders);
+        $invoice = $this->invoiceManagement->prepareInvoice($order);
+
+        self::assertEquals($invoice->isLast(), true);
+    }
 }