From fe4b90edc0ead9c6c77d606101bfbf568a963fb4 Mon Sep 17 00:00:00 2001
From: UndefinedOffset <echipman@webbuildersgroup.com>
Date: Wed, 18 Apr 2018 10:45:51 -0300
Subject: [PATCH] FIX: Duplicating many_many relationships looses the extra
 fields in 4.0

---
 src/ORM/DataObject.php                             | 14 +++++++++++++-
 tests/php/ORM/DataObjectDuplicationTest.php        |  8 +++++++-
 tests/php/ORM/DataObjectDuplicationTest/Class1.php |  6 ++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/src/ORM/DataObject.php b/src/ORM/DataObject.php
index f8ad2560c..c6099fd7d 100644
--- a/src/ORM/DataObject.php
+++ b/src/ORM/DataObject.php
@@ -459,8 +459,20 @@ class DataObject extends ViewableData implements DataObjectInterface, i18nEntity
         // Copy all components from source to destination
         $source = $sourceObject->getManyManyComponents($manyManyName);
         $dest = $destinationObject->getManyManyComponents($manyManyName);
+
+        if ($source instanceof UnsavedRelationList) {
+            $extraFieldNames = array();
+        } else {
+            $extraFieldNames = $source->getExtraFields();
+        }
+
         foreach ($source as $item) {
-            $dest->add($item);
+            // Merge extra fields
+            $extraFields = array();
+            foreach ($extraFieldNames as $fieldName => $fieldType) {
+                $extraFields[$fieldName] = $item->getField($fieldName);
+            }
+            $dest->add($item, $extraFields);
         }
     }
 
diff --git a/tests/php/ORM/DataObjectDuplicationTest.php b/tests/php/ORM/DataObjectDuplicationTest.php
index b3186d53f..09c88d821 100644
--- a/tests/php/ORM/DataObjectDuplicationTest.php
+++ b/tests/php/ORM/DataObjectDuplicationTest.php
@@ -102,7 +102,7 @@ class DataObjectDuplicationTest extends SapphireTest
 
         //create relations
         $one->twos()->add($two);
-        $one->threes()->add($three);
+        $one->threes()->add($three, array('TestExtra'=>'three'));
 
         $one = DataObject::get_by_id(DataObjectDuplicationTest\Class1::class, $one->ID);
         $two = DataObject::get_by_id(DataObjectDuplicationTest\Class2::class, $two->ID);
@@ -161,6 +161,12 @@ class DataObjectDuplicationTest extends SapphireTest
             $threeCopy->ones()->First()->ID,
             "Match between relation of copy and the original"
         );
+
+        $this->assertEquals(
+            'three',
+            $oneCopy->threes()->byID($three->ID)->TestExtra,
+            "Match between extra field of copy and the original"
+        );
     }
 
     public function testDuplicateManyManyFiltered()
diff --git a/tests/php/ORM/DataObjectDuplicationTest/Class1.php b/tests/php/ORM/DataObjectDuplicationTest/Class1.php
index 57a6c8302..b3a5fd3ef 100644
--- a/tests/php/ORM/DataObjectDuplicationTest/Class1.php
+++ b/tests/php/ORM/DataObjectDuplicationTest/Class1.php
@@ -20,4 +20,10 @@ class Class1 extends DataObject implements TestOnly
     private static $many_many = array(
         'threes' => Class3::class
     );
+
+    private static $many_many_extraFields = array(
+        'threes' => array(
+            'TestExtra' => 'Varchar'
+        )
+    );
 }