MAGETWO-72861: Category edit performance issue - for 2.3

- Add strict types;
- Add scalar type hinting;

Author: adifucan

app/code/Magento/Catalog/Model/Category/Product/PositionResolver.php

@@ -3,6 +3,8 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
+
 namespace Magento\Catalog\Model\Category\Product;
 
 /**
@@ -37,7 +39,7 @@ protected function _construct()
      * @param int $categoryId
      * @return array
      */
-    public function getPositions(int $categoryId)
+    public function getPositions(int $categoryId): array
     {
         $connection = $this->getConnection();
 

app/code/Magento/Catalog/Test/Unit/Model/Category/Product/PositionResolverTest.php

@@ -3,6 +3,8 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
+
 namespace Magento\Catalog\Test\Unit\Model\Category\Product;
 
 use Magento\Framework\TestFramework\Unit\Helper\ObjectManager;

app/code/Magento/CatalogRule/Model/Indexer/IndexBuilder/ProductLoader.php

@@ -3,6 +3,8 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
+
 namespace Magento\CatalogRule\Model\Indexer\IndexBuilder;
 
 use Magento\Catalog\Api\ProductRepositoryInterface;
@@ -42,7 +44,7 @@ public function __construct(
      * @param array $productIds
      * @return ProductInterface[]
      */
-    public function getProducts($productIds)
+    public function getProducts(array $productIds): array
     {
         $this->searchCriteriaBuilder->addFilter('entity_id', $productIds, 'in');
         $searchCriteria = $this->searchCriteriaBuilder->create();

app/code/Magento/CatalogRule/Plugin/Indexer/Category.php

@@ -36,7 +36,7 @@ public function afterSave(
     ) {
         /** @var \Magento\Catalog\Model\Category $result */
         $productIds = $result->getAffectedProductIds();
-        if ($productIds && !$this->productRuleProcessor->isIndexerScheduled()) {
+        if (!empty($productIds) && !$this->productRuleProcessor->isIndexerScheduled()) {
             $this->productRuleProcessor->reindexList($productIds);
         }
         return $result;

app/code/Magento/CatalogRule/Test/Unit/Model/Indexer/IndexBuilder/ProductLoaderTest.php

@@ -3,6 +3,7 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
 
 namespace Magento\CatalogRule\Test\Unit\Model\Indexer\IndexBuilder;
 

app/code/Magento/CatalogUrlRewrite/Observer/CategoryProcessUrlRewriteSavingObserver.php

@@ -85,7 +85,7 @@ public function execute(\Magento\Framework\Event\Observer $observer)
         $mapsGenerated = false;
         if ($category->dataHasChangedFor('url_key')
             || $category->dataHasChangedFor('is_anchor')
-            || $category->getChangedProductIds()
+            || !empty($category->getChangedProductIds())
         ) {
             if ($category->dataHasChangedFor('url_key')) {
                 $categoryUrlRewriteResult = $this->categoryUrlRewriteGenerator->generate($category);