MAGETWO-33109 : Refactor code that uses customer builders in Quote module

 -- changes from code review

Author: Robert He

app/code/Magento/Quote/Model/Observer/Frontend/Quote/Address/CollectTotals.php

@@ -34,11 +34,6 @@ class CollectTotals
      */
     protected $groupManagement;
 
-    /**
-     * @var \Magento\Framework\Api\DataObjectHelper
-     */
-    protected $dataObjectHelper;
-
     /**
      * Initialize dependencies.
      *
@@ -47,22 +42,19 @@ class CollectTotals
      * @param VatValidator $vatValidator
      * @param \Magento\Customer\Api\Data\CustomerInterfaceFactory $customerDataFactory
      * @param \Magento\Customer\Api\GroupManagementInterface $groupManagement
-     * @param \Magento\Framework\Api\DataObjectHelper $dataObjectHelper
      */
     public function __construct(
         \Magento\Customer\Helper\Address $customerAddressHelper,
         \Magento\Customer\Model\Vat $customerVat,
         VatValidator $vatValidator,
         \Magento\Customer\Api\Data\CustomerInterfaceFactory $customerDataFactory,
-        \Magento\Customer\Api\GroupManagementInterface $groupManagement,
-        \Magento\Framework\Api\DataObjectHelper $dataObjectHelper
+        \Magento\Customer\Api\GroupManagementInterface $groupManagement
     ) {
         $this->customerVat = $customerVat;
         $this->customerAddressHelper = $customerAddressHelper;
         $this->vatValidator = $vatValidator;
         $this->customerDataFactory = $customerDataFactory;
         $this->groupManagement = $groupManagement;
-        $this->dataObjectHelper = $dataObjectHelper;
     }
 
     /**
@@ -107,8 +99,7 @@ public function dispatch(\Magento\Framework\Event\Observer $observer)
         if ($groupId) {
             $quoteAddress->setPrevQuoteCustomerGroupId($quote->getCustomerGroupId());
             $quote->setCustomerGroupId($groupId);
-            $customer = $this->customerDataFactory->create();
-            $this->dataObjectHelper->populateWithArray($customer, ['group_id' => $groupId]);
+            $customer->setGroupId($groupId);
             $quote->setCustomer($customer);
         }
     }

app/code/Magento/Quote/Model/Quote.php

@@ -831,16 +831,16 @@ public function setCustomer(\Magento\Customer\Api\Data\CustomerInterface $custom
         /* @TODO: Remove the method after all external usages are refactored in MAGETWO-19930 */
         $this->_customer = $customer;
         $this->setCustomerId($customer->getId());
-        $customerData = $this->customerDataFactory->create();
-        $customerData->populate($customer);
-        $customerData->setAddresses([]);
+        $origAddresses = $customer->getAddresses();
+        $customer->setAddresses([]);
         $customerDataFlatArray = $this->objectFactory->create(
             $this->extensibleDataObjectConverter->toFlatArray(
-                $customerData,
+                $customer,
                 [],
                 '\Magento\Customer\Api\Data\CustomerInterface'
             )
         );
+        $customer->setAddresses($origAddresses);
         $this->_objectCopyService->copyFieldsetToTarget('customer_account', 'to_quote', $customerDataFlatArray, $this);
 
         return $this;

dev/tests/unit/testsuite/Magento/Quote/Model/Observer/Frontend/Quote/Address/CollectTotalsTest.php

@@ -280,7 +280,7 @@ public function testDispatchWithDefaultCustomerGroupId()
             ->method('setPrevQuoteCustomerGroupId')
             ->with('customerGroupId');
         $this->quoteMock->expects($this->once())->method('setCustomerGroupId')->with('defaultCustomerGroupId');
-        $this->dataObjectHelperMock->expects($this->once())
+        $this->dataObjectHelperMock->expects($this->never())
             ->method('populateWithArray')
             ->with($this->customerMock, ['group_id' => 'defaultCustomerGroupId'])
             ->will($this->returnSelf());
@@ -336,7 +336,7 @@ public function testDispatchWithCustomerCountryInEU()
 
         $this->quoteMock->expects($this->once())->method('setCustomerGroupId')->with('customerGroupId');
         $this->quoteMock->expects($this->once())->method('setCustomer')->with($this->customerMock);
-        $this->dataObjectHelperMock->expects($this->once())
+        $this->dataObjectHelperMock->expects($this->never())
             ->method('populateWithArray')
             ->with($this->customerMock, ['group_id' => 'customerGroupId'])
             ->will($this->returnSelf());

lib/internal/Magento/Framework/Api/DataObjectHelper.php

@@ -175,6 +175,7 @@ protected function setComplexValue(
      * @param ExtensibleDataInterface $firstDataObject
      * @param ExtensibleDataInterface $secondDataObject
      * @return $this
+     * @throws \LogicException
      */
     public function mergeDataObjects(
         $className,
@@ -184,10 +185,8 @@ public function mergeDataObjects(
         if (!$firstDataObject instanceof $className || !$secondDataObject instanceof $className) {
             throw new \LogicException('Wrong prototype object given. It can only be of "' . $className . '" type.');
         }
-        $firstObjectArray = $this->objectProcessor->buildOutputDataArray($firstDataObject, $className);
         $secondObjectArray = $this->objectProcessor->buildOutputDataArray($secondDataObject, $className);
-        $this->_setDataValues($this, $firstObjectArray);
-        $this->_setDataValues($this, $secondObjectArray);
+        $this->_setDataValues($firstDataObject, $secondObjectArray);
         return $this;
     }
 }