Checkout / Sales Rules / Get rid of redundant DB query

app/code/Magento/Rule/Model/Condition/Product/AbstractProduct.php

@@ -12,6 +12,7 @@
 /**
  * Abstract Rule product condition data model
  *
+ * phpcs:disable Magento2.Classes.AbstractApi
  * @SuppressWarnings(PHPMD.ExcessiveClassComplexity)
  * @SuppressWarnings(PHPMD.CouplingBetweenObjects)
  * @api
@@ -657,23 +658,11 @@ public function validateByEntityId($productId)
      * Retrieve category ids where product is available
      *
      * @param int $productId
-     * @return array
+     * @return int[]
      */
     protected function _getAvailableInCategories($productId)
     {
-        return $this->_productResource->getConnection()
-            ->fetchCol(
-                $this->_productResource->getConnection()
-                    ->select()
-                    ->distinct()
-                    ->from(
-                        $this->_productResource->getTable('catalog_category_product'),
-                        ['category_id']
-                    )->where(
-                        'product_id = ?',
-                        $productId
-                    )
-            );
+        return $this->productCategoryList->getCategoryIds($productId);
     }
 
     /**

app/code/Magento/SalesRule/Test/Unit/Model/Rule/Condition/ProductTest.php

@@ -9,6 +9,7 @@
 
 use Magento\Backend\Helper\Data;
 use Magento\Catalog\Api\ProductRepositoryInterface;
+use Magento\Catalog\Model\ProductCategoryList;
 use Magento\Catalog\Model\ProductFactory;
 use Magento\Catalog\Model\ResourceModel\Product;
 use Magento\Directory\Model\CurrencyFactory;
@@ -34,6 +35,7 @@
  */
 class ProductTest extends TestCase
 {
+    const STUB_CATEGORY_ID = 5;
     /** @var SalesRuleProduct */
     protected $model;
 
@@ -70,6 +72,9 @@ class ProductTest extends TestCase
     /** @var Select|MockObject */
     protected $selectMock;
 
+    /** @var MockObject|ProductCategoryList */
+    private $productCategoryListMock;
+
     /**
      * Setup the test
      */
@@ -138,6 +143,10 @@ protected function setUp(): void
         $this->collectionMock = $this->getMockBuilder(Collection::class)
             ->disableOriginalConstructor()
             ->getMock();
+        $this->productCategoryListMock = $this->getMockBuilder(ProductCategoryList::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['getCategoryIds'])
+            ->getMock();
         $this->format = new Format(
             $this->getMockBuilder(ScopeResolverInterface::class)
                 ->disableOriginalConstructor()
@@ -158,7 +167,9 @@ protected function setUp(): void
             $this->productRepositoryMock,
             $this->productMock,
             $this->collectionMock,
-            $this->format
+            $this->format,
+            [],
+            $this->productCategoryListMock
         );
     }
 
@@ -228,28 +239,22 @@ public function testValidateCategoriesIgnoresVisibility(): void
             ->setMethods(['getAttribute', 'getId', 'setQuoteItemQty', 'setQuoteItemPrice'])
             ->getMock();
         $product
-            ->expects($this->any())
             ->method('setQuoteItemQty')
             ->willReturnSelf();
         $product
-            ->expects($this->any())
             ->method('setQuoteItemPrice')
             ->willReturnSelf();
         /* @var AbstractItem|MockObject $item */
         $item = $this->getMockBuilder(AbstractItem::class)
             ->disableOriginalConstructor()
-            ->setMethods(['getProduct'])
+            ->onlyMethods(['getProduct'])
             ->getMockForAbstractClass();
         $item->expects($this->any())
             ->method('getProduct')
             ->willReturn($product);
         $this->model->setAttribute('category_ids');
-
-        $this->selectMock
-            ->expects($this->once())
-            ->method('where')
-            ->with($this->logicalNot($this->stringContains('visibility')), $this->anything(), $this->anything());
-
+        $this->productCategoryListMock->method('getCategoryIds')
+            ->willReturn([self::STUB_CATEGORY_ID]);
         $this->model->validate($item);
     }