MAGETWO-70491: Issues 6729, 6457, 7362: Configurable product price options provider #9796

Author: Oleksii Korshenko

app/code/Magento/ConfigurableProduct/Pricing/Price/LowestPriceOptionsProvider.php

@@ -63,7 +63,9 @@ public function getProducts(ProductInterface $product)
             );
 
             $this->linkedProductMap[$product->getId()] = $this->collectionFactory->create()
-                ->addAttributeToSelect(['price', 'special_price', 'special_from_date', 'special_to_date'])
+                ->addAttributeToSelect(
+                    ['price', 'special_price', 'special_from_date', 'special_to_date', 'tax_class_id']
+                )
                 ->addIdFilter($productIds)
                 ->getItems();
         }

app/code/Magento/ConfigurableProduct/Test/Unit/Pricing/Price/LowestPriceOptionsProviderTest.php

@@ -90,7 +90,7 @@ public function testGetProducts()
         $this->productCollection
             ->expects($this->once())
             ->method('addAttributeToSelect')
-            ->with(['price', 'special_price', 'special_from_date', 'special_to_date'])
+            ->with(['price', 'special_price', 'special_from_date', 'special_to_date', 'tax_class_id'])
             ->willReturnSelf();
         $this->productCollection->expects($this->once())->method('addIdFilter')->willReturnSelf();
         $this->productCollection->expects($this->once())->method('getItems')->willReturn($linkedProducts);