From c66df67c4946c52ccd70230299b49459dadd7e29 Mon Sep 17 00:00:00 2001
From: sol HYUN <solsol9057@gmail.com>
Date: Mon, 5 Dec 2016 19:16:01 +0900
Subject: [PATCH] Modify 'to_internal_value' method for handling list

modified the 'get_value' method in fields.py,
The value of primitive_value is a list of values to match the field.

Validate the primitive_value (list) elements one by one using the
run_validation method.

The verified value is appended to the validated_list

Finally, only when there are two or more elements of validated_list, they are
returned as a list.
---
 rest_framework/serializers.py | 31 +++++++++++++++++--------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index 8e7206fd8..cec87e881 100644
--- a/rest_framework/serializers.py
+++ b/rest_framework/serializers.py
@@ -454,26 +454,29 @@ class Serializer(BaseSerializer):
         ret = OrderedDict()
         errors = OrderedDict()
         fields = self._writable_fields
-
         for field in fields:
             validate_method = getattr(self, 'validate_' + field.field_name, None)
             primitive_value = field.get_value(data)
-            try:
-                validated_value = field.run_validation(primitive_value)
-                if validate_method is not None:
-                    validated_value = validate_method(validated_value)
-            except ValidationError as exc:
-                errors[field.field_name] = exc.detail
-            except DjangoValidationError as exc:
-                errors[field.field_name] = get_error_detail(exc)
-            except SkipField:
-                pass
+            validated_list = []
+            for inner_data in primitive_value:
+                try:
+                    validated_value = field.run_validation(inner_data)
+                    validated_list.append(validated_value)
+                    if validate_method is not None:
+                        validated_list.append(validate_method(validated_value))
+                except ValidationError as exc:
+                    errors[field.field_name] = exc.detail
+                except DjangoValidationError as exc:
+                    errors[field.field_name] = get_error_detail(exc)
+                except SkipField:
+                    pass
             else:
-                set_value(ret, field.source_attrs, validated_value)
-
+                if len(validated_list) > 1:
+                    set_value(ret, field.source_attrs, validated_list)
+                else:
+                    set_value(ret, field.source_attrs, validated_list[0])
         if errors:
             raise ValidationError(errors)
-
         return ret
 
     def to_representation(self, instance):