MAGETWO-32364: Improve performance in pricing framework

Author: Yu Tang

app/code/Magento/Catalog/Model/Product.php

@@ -776,8 +776,10 @@ public function afterSave()
      */
     public function setQty($qty)
     {
-        $this->setData('qty', $qty);
-        $this->reloadPriceInfo();
+        if ($this->getData('qty') != $qty) {
+            $this->setData('qty', $qty);
+            $this->reloadPriceInfo();
+        }
         return $this;
     }
 

dev/tests/unit/testsuite/Magento/Catalog/Model/ProductTest.php

@@ -423,10 +423,16 @@ public function testGetPriceInfo()
      */
     public function testSetQty()
     {
-        $this->productTypeInstanceMock->expects($this->once())
+        $this->productTypeInstanceMock->expects($this->exactly(2))
             ->method('getPriceInfo')
             ->with($this->equalTo($this->model))
             ->will($this->returnValue($this->_priceInfoMock));
+
+        //initialize the priceInfo field
+        $this->model->getPriceInfo();
+        //Calling setQty will reset the priceInfo field
+        $this->assertEquals($this->model, $this->model->setQty(1));
+        //Call the setQty method with the same qty, getPriceInfo should not be called this time
         $this->assertEquals($this->model, $this->model->setQty(1));
         $this->assertEquals($this->model->getPriceInfo(), $this->_priceInfoMock);
     }

dev/tests/unit/testsuite/Magento/Framework/Pricing/Price/CollectionTest.php

@@ -79,6 +79,8 @@ public function testGet()
             )
             ->will($this->returnValue($this->priceMock));
         $this->assertEquals($this->priceMock, $this->collection->get('regular_price'));
+        //Calling the get method again with the same code, cached copy should be used
+        $this->assertEquals($this->priceMock, $this->collection->get('regular_price'));
     }
 
     /**

lib/internal/Magento/Framework/Pricing/Price/Collection.php

@@ -42,6 +42,13 @@ class Collection implements \Iterator
      */
     protected $excludes;
 
+    /**
+     * Cached price models
+     *
+     * @var array
+     */
+    protected $priceModels;
+
     /**
      * Constructor
      *
@@ -60,6 +67,7 @@ public function __construct(
         $this->priceFactory = $priceFactory;
         $this->pool = $pool;
         $this->quantity = $quantity;
+        $this->priceModels = [];
     }
 
     /**
@@ -120,10 +128,13 @@ public function valid()
      */
     public function get($code)
     {
-        return $this->priceFactory->create(
-            $this->saleableItem,
-            $this->pool[$code],
-            $this->quantity
-        );
+        if (!isset($this->priceModels[$code])) {
+            $this->priceModels[$code] = $this->priceFactory->create(
+                $this->saleableItem,
+                $this->pool[$code],
+                $this->quantity
+            );
+        }
+        return $this->priceModels[$code];
     }
 }