MC-32175: [Page builder] Category page returns 500 error

Author: nikita-shcherbatykh

app/code/Magento/Catalog/Block/Product/View.php

@@ -323,9 +323,9 @@ public function getQuantityValidators()
      */
     public function getIdentities()
     {
-        $identities = $this->getProduct()->getIdentities();
+        $product = $this->getProduct();
 
-        return $identities;
+        return $product ? $product->getIdentities() : [];
     }
 
     /**

app/code/Magento/Review/Block/Product/View.php

@@ -82,13 +82,20 @@ public function __construct(
      */
     protected function _toHtml()
     {
-        $this->getProduct()->setShortDescription(null);
+        $product = $this->getProduct();
+
+        if (!$product) {
+            return '';
+        }
+
+        $product->setShortDescription(null);
 
         return parent::_toHtml();
     }
 
     /**
      * Replace review summary html with more detailed review summary
+     *
      * Reviews collection count will be jerked here
      *
      * @param \Magento\Catalog\Model\Product $product

app/code/Magento/Review/Block/Product/View/ListView.php

@@ -55,7 +55,10 @@ protected function _prepareLayout()
      */
     protected function _beforeToHtml()
     {
-        $this->getReviewsCollection()->load()->addRateVotes();
+        if ($this->getProductId()) {
+            $this->getReviewsCollection()->load()->addRateVotes();
+        }
+
         return parent::_beforeToHtml();
     }
 

app/code/Magento/Review/Test/Unit/Block/Product/ListViewTest.php

@@ -0,0 +1,49 @@
+<?php
+/**
+ * Test class for \Magento\Review\Block\Product\View\ListView
+ *
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+namespace Magento\Review\Test\Unit\Block\Product;
+
+use Magento\Framework\TestFramework\Unit\Helper\ObjectManager;
+use Magento\Review\Block\Product\View\ListView;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Class ViewTest
+ */
+class ListViewTest extends TestCase
+{
+    /**
+     * @var ListView
+     */
+    private $listView;
+
+    /**
+     * @var ObjectManager
+     */
+    private $objectManager;
+
+    /**
+     * @inheritDoc
+     */
+    protected function setUp()
+    {
+        $this->objectManager = new ObjectManager($this);
+        $this->listView = $this->objectManager->getObject(
+            ListView::class
+        );
+    }
+
+    /**
+     * Validate that ListView->toHtml() would not crush if provided product is null
+     */
+    public function testBlockShouldNotFailWithNullProduct()
+    {
+        $output = $this->listView->toHtml();
+        $this->assertEquals('', $output);
+    }
+}