Don't persist relation changes in ModelSerializer#restore_object()

1 files changed, 17 insertions, 17 deletions

diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index ed173d85..24674f2a 100644
--- a/rest_framework/serializers.py
+++ b/rest_framework/serializers.py
@@ -498,28 +498,28 @@ class ModelSerializer(Serializer):
         self.m2m_data = {}
         self.related_data = {}
 
+        # Reverse fk relations
+        for (obj, model) in self.opts.model._meta.get_all_related_objects_with_model():
+            field_name = obj.field.related_query_name()
+            if field_name in attrs:
+                self.related_data[field_name] = attrs.pop(field_name)
+
+        # Reverse m2m relations
+        for (obj, model) in self.opts.model._meta.get_all_related_m2m_objects_with_model():
+            field_name = obj.field.related_query_name()
+            if field_name in attrs:
+                self.m2m_data[field_name] = attrs.pop(field_name)
+
+        # Forward m2m relations
+        for field in self.opts.model._meta.many_to_many:
+            if field.name in attrs:
+                self.m2m_data[field.name] = attrs.pop(field.name)
+
         if instance is not None:
             for key, val in attrs.items():
                 setattr(instance, key, val)
 
         else:
-            # Reverse fk relations
-            for (obj, model) in self.opts.model._meta.get_all_related_objects_with_model():
-                field_name = obj.field.related_query_name()
-                if field_name in attrs:
-                    self.related_data[field_name] = attrs.pop(field_name)
-
-            # Reverse m2m relations
-            for (obj, model) in self.opts.model._meta.get_all_related_m2m_objects_with_model():
-                field_name = obj.field.related_query_name()
-                if field_name in attrs:
-                    self.m2m_data[field_name] = attrs.pop(field_name)
-
-            # Forward m2m relations
-            for field in self.opts.model._meta.many_to_many:
-                if field.name in attrs:
-                    self.m2m_data[field.name] = attrs.pop(field.name)
-
             instance = self.opts.model(**attrs)
 
         try: