MAGETWO-52124: Simple product special price lost if use it in grouped product

Author: kandy

app/code/Magento/GroupedProduct/Model/Product/Type/Grouped.php

@@ -202,7 +202,7 @@ public function getAssociatedProducts($product)
             $collection = $this->getAssociatedProductCollection(
                 $product
             )->addAttributeToSelect(
-                ['name', 'price']
+                ['name', 'price',  'special_price', 'special_from_date', 'special_to_date']
             )->addFilterByRequiredOptions()->setPositionOrder()->addStoreFilter(
                 $this->getStoreFilter($product)
             )->addAttributeToFilter(

dev/tests/integration/testsuite/Magento/GroupedProduct/Pricing/Price/FinalPriceTest.php

@@ -0,0 +1,78 @@
+<?php
+/**
+ * Copyright © 2015 Magento. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+namespace testsuite\Magento\GroupedProduct\Pricing\Price;
+
+use Magento\Catalog\Api\Data\ProductTierPriceInterface;
+use Magento\GroupedProduct\Pricing\Price\FinalPrice;
+use Magento\TestFramework\Helper\Bootstrap;
+
+class FinalPriceTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @magentoDataFixture Magento/GroupedProduct/_files/product_grouped.php
+     * @magentoAppIsolation enabled
+     */
+    public function testFinalPrice()
+    {
+        $productRepository = Bootstrap::getObjectManager()
+            ->get('\Magento\Catalog\Api\ProductRepositoryInterface');
+        /** @var $product \Magento\Catalog\Model\Product */
+        $product = $productRepository->get('grouped-product');
+
+        $this->assertEquals(10, $product->getPriceInfo()->getPrice(FinalPrice::PRICE_CODE)->getValue());
+    }
+
+    /**
+     * @magentoDataFixture Magento/GroupedProduct/_files/product_grouped.php
+     * @magentoAppIsolation enabled
+     */
+    public function testFinalPriceWithTearPrice()
+    {
+        $productRepository = Bootstrap::getObjectManager()
+            ->get('\Magento\Catalog\Api\ProductRepositoryInterface');
+        /** @var ProductTierPriceInterface $tierPrice */
+        $tierPrice = Bootstrap::getObjectManager()->create(ProductTierPriceInterface::class);
+        $tierPrice->setQty(1);
+        $tierPrice->setCustomerGroupId(\Magento\Customer\Model\GroupManagement::CUST_GROUP_ALL);
+        $tierPrice->setValue(5);
+
+
+        /** @var $simpleProduct \Magento\Catalog\Api\Data\ProductInterface */
+        $simpleProduct = $productRepository->get('simple');
+        $simpleProduct->setTierPrices([
+            $tierPrice
+        ]);
+        $productRepository->save($simpleProduct);
+
+
+        /** @var $product \Magento\Catalog\Model\Product */
+        $product = $productRepository->get('grouped-product');
+        $this->assertEquals(5, $product->getPriceInfo()->getPrice(FinalPrice::PRICE_CODE)->getValue());
+    }
+
+    /**
+     * @magentoDataFixture Magento/GroupedProduct/_files/product_grouped.php
+     * @magentoAppIsolation enabled
+     */
+    public function testFinalPriceWithSpecialPrice()
+    {
+        $productRepository = Bootstrap::getObjectManager()
+            ->get('\Magento\Catalog\Api\ProductRepositoryInterface');
+
+
+
+        /** @var $simpleProduct \Magento\Catalog\Api\Data\ProductInterface */
+        $simpleProduct = $productRepository->get('simple');
+        $simpleProduct->setCustomAttribute('special_price', 6);
+        $productRepository->save($simpleProduct);
+
+
+        /** @var $product \Magento\Catalog\Model\Product */
+        $product = $productRepository->get('grouped-product');
+        $this->assertEquals(6, $product->getPriceInfo()->getPrice(FinalPrice::PRICE_CODE)->getValue());
+    }
+}