MAGETWO-70377: [GitHub] Tier price saving percentage wrong when VAT is included in price #8833

Author: Dmytro Voskoboinikov

app/code/Magento/Catalog/Pricing/Price/TierPrice.php

@@ -215,14 +215,21 @@ protected function getBasePrice()
     }
 
     /**
+     * Calculates savings percentage according to the given tier price amount
+     * and related product price amount.
+     *
      * @param AmountInterface $amount
+     *
      * @return float
      */
     public function getSavePercent(AmountInterface $amount)
     {
+        $productPriceAmount = $this->priceInfo->getPrice(
+            FinalPrice::PRICE_CODE
+        )->getAmount();
+
         return round(
-            100 - ((100 / $this->priceInfo->getPrice(FinalPrice::PRICE_CODE)->getValue())
-                * $amount->getBaseAmount())
+            100 - ((100 / $productPriceAmount->getValue()) * $amount->getValue())
         );
     }
 

app/code/Magento/Catalog/Test/Unit/Pricing/Price/TierPriceTest.php

@@ -10,6 +10,8 @@
 
 use Magento\Catalog\Pricing\Price\TierPrice;
 use Magento\Catalog\Pricing\Price\FinalPrice;
+use Magento\Framework\Pricing\Amount\AmountInterface;
+use Magento\Framework\Pricing\Price\PriceInterface;
 use Magento\Customer\Model\Group;
 use Magento\Customer\Model\GroupManagement;
 
@@ -250,7 +252,7 @@ public function testGetterTierPriceList($tierPrices, $basePrice, $expectedResult
     {
         $this->product->setData(TierPrice::PRICE_CODE, $tierPrices);
 
-        $price = $this->createMock(\Magento\Framework\Pricing\Price\PriceInterface::class);
+        $price = $this->createMock(PriceInterface::class);
         $price->expects($this->any())->method('getValue')->will($this->returnValue($basePrice));
 
         $this->calculator->expects($this->atLeastOnce())->method('getAmount')
@@ -341,27 +343,37 @@ public function providerForGetterTierPriceList()
     }
 
     /**
-     * @covers \Magento\Catalog\Pricing\Price\TierPrice::__construct
-     * @covers \Magento\Catalog\Pricing\Price\TierPrice::getSavePercent
-     * @covers \Magento\Catalog\Pricing\Price\TierPrice::getBasePrice
+     * @param float $basePrice
+     * @param float $tierPrice
+     * @param float $savedPercent
+     *
      * @dataProvider dataProviderGetSavePercent
      */
     public function testGetSavePercent($basePrice, $tierPrice, $savedPercent)
     {
-        $price = $this->createMock(\Magento\Framework\Pricing\Price\PriceInterface::class);
+        /** @var AmountInterface|\PHPUnit_Framework_MockObject_MockObject $amount */
+        $amount = $this->getMockForAbstractClass(AmountInterface::class);
 
-        $this->priceInfo->expects(static::atLeastOnce())
-            ->method('getPrice')
-            ->with(FinalPrice::PRICE_CODE)
-            ->willReturn($price);
-        $price->expects(static::atLeastOnce())
+        $amount->expects($this->any())
+            ->method('getValue')
+            ->willReturn($tierPrice);
+
+        $basePriceAmount = $this->getMockForAbstractClass(AmountInterface::class);
+
+        $basePriceAmount->expects($this->any())
             ->method('getValue')
             ->willReturn($basePrice);
 
-        $amount = $this->getMockForAbstractClass(\Magento\Framework\Pricing\Amount\AmountInterface::class);
-        $amount->expects($this->atLeastOnce())
-            ->method('getBaseAmount')
-            ->will($this->returnValue($tierPrice));
+        $price = $this->getMockForAbstractClass(PriceInterface::class);
+
+        $price->expects($this->any())
+            ->method('getAmount')
+            ->willReturn($basePriceAmount);
+
+        $this->priceInfo->expects($this->any())
+            ->method('getPrice')
+            ->with(FinalPrice::PRICE_CODE)
+            ->willReturn($price);
 
         $this->assertEquals($savedPercent, $this->model->getSavePercent($amount));
     }