B2B-2243: Optimize addProductsToCart operations

Author: Roman Hanin

app/code/Magento/Quote/Model/Cart/AddProductsToCart.php

@@ -191,14 +191,15 @@ private function addItemToCart(Quote $cart, Data\CartItem $cartItem, int $cartIt
                     __('Could not find a product with SKU "%sku"', ['sku' => $sku])->render(),
                     $cartItemPosition
                 );
-            }
-            try {
-                $result = $cart->addProduct($product, $this->requestBuilder->build($cartItem));
-            } catch (\Throwable $e) {
-                $errors[] = $this->createError(
-                    __($e->getMessage())->render(),
-                    $cartItemPosition
-                );
+            } else {
+                try {
+                    $result = $cart->addProduct($product, $this->requestBuilder->build($cartItem));
+                } catch (\Throwable $e) {
+                    $errors[] = $this->createError(
+                        __($e->getMessage())->render(),
+                        $cartItemPosition
+                    );
+                }
             }
 
             if (is_string($result)) {

app/code/Magento/Quote/Model/Cart/ProductReader.php

@@ -50,7 +50,7 @@ public function __construct(
     }
 
     /**
-     * @inheirtDoc
+     * @inheritDoc
      */
     public function loadProducts(array $skus, int $storeId): void
     {
@@ -68,7 +68,7 @@ public function loadProducts(array $skus, int $storeId): void
     }
 
     /**
-     * @inheirtdoc
+     * @inheritDoc
      */
     public function getProductBySku(string $sku) : ?ProductInterface
     {

app/code/Magento/Quote/Model/ResourceModel/Quote/Item/Collection.php

@@ -382,7 +382,7 @@ private function removeItemsWithAbsentProducts(): void
 
         $productCollection = $this->_productCollectionFactory->create()->addIdFilter($this->_productIds);
         $existingProductsIds = $productCollection->getAllIds();
-        $absentProductsIds = array_diff($this->_productIds, $existingProductsIds);
+        $absentProductsIds = array_unique(array_diff($this->_productIds, $existingProductsIds));
         // Remove not existing products from items collection
         if (!empty($absentProductsIds)) {
             foreach ($absentProductsIds as $productIdToExclude) {