MAGETWO-72280: [Backport] Tier price saving percentage wrong when VAT is included in price #8833 2.1.x

Author: interio-zz

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

@@ -7,6 +7,7 @@
 namespace Magento\Bundle\Pricing\Price;
 
 use Magento\Catalog\Pricing\Price\RegularPrice;
+use Magento\Framework\Pricing\Amount\AmountInterface;
 
 /**
  * Bundle tier prices model
@@ -89,4 +90,13 @@ public function isPercentageDiscount()
     {
         return true;
     }
+
+    /**
+     * @param AmountInterface $amount
+     * @return float
+     */
+    public function getSavePercent(AmountInterface $amount)
+    {
+        return round($amount->getBaseAmount());
+    }
 }

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

@@ -181,27 +181,11 @@ public function providerForGetterTierPriceList()
     /**
      * @dataProvider providerForTestGetSavePercent
      */
-    public function testGetSavePercent($baseAmount, $tierPrice, $savePercent)
+    public function testGetSavePercent($baseAmount, $savePercent)
     {
         /** @var \Magento\Framework\Pricing\Amount\AmountInterface|\PHPUnit_Framework_MockObject_MockObject $amount */
         $amount = $this->getMockForAbstractClass('Magento\Framework\Pricing\Amount\AmountInterface');
-        $amount->expects($this->any())
-            ->method('getValue')
-            ->will($this->returnValue($tierPrice));
-
-        $priceAmount = $this->getMockForAbstractClass('Magento\Framework\Pricing\Amount\AmountInterface');
-        $priceAmount->expects($this->any())
-            ->method('getValue')
-            ->will($this->returnValue($baseAmount));
-
-        $price = $this->getMock('Magento\Framework\Pricing\Price\PriceInterface');
-        $price->expects($this->any())
-            ->method('getAmount')
-            ->will($this->returnValue($priceAmount));
-
-        $this->priceInfo->expects($this->any())
-            ->method('getPrice')
-            ->will($this->returnValue($price));
+        $amount->expects($this->once())->method('getBaseAmount')->willReturn($baseAmount);
 
         $this->assertEquals($savePercent, $this->model->getSavePercent($amount));
     }
@@ -212,8 +196,10 @@ public function testGetSavePercent($baseAmount, $tierPrice, $savePercent)
     public function providerForTestGetSavePercent()
     {
         return [
-            'no fraction' => [9.0000, 8.1, 10],
-            'lower half'  => [9.1234, 8.3, 9],
+            'no fraction' => [10.0000, 10],
+            'lower half'  => [10.1234, 10],
+            'half way'    => [10.5000, 11],
+            'upper half'  => [10.6789, 11],
         ];
     }
 }