Make sure discounts with quantities > 1 are handled correctly

Author: Andy Coates

src/Message/AbstractRequest.php

@@ -178,11 +178,11 @@ protected function getItemData()
         }
         if ($cartHasDiscounts) {
             $discounts = $xml->addChild('discounts');
-            foreach ($items as $discountItems) {
-                if ($discountItems->getPrice() < 0) {
+            foreach ($items as $discountItem) {
+                if ($discountItem->getPrice() < 0) {
                     $discount = $discounts->addChild('discount');
-                    $discount->addChild('fixed', $discountItems->getPrice() * -1);
-                    $discount->description = $discountItems->getName();
+                    $discount->addChild('fixed', ($discountItem->getPrice() * $discountItem->getQuantity()) * -1);
+                    $discount->description = $discountItem->getName();
                 }
             }
         }