From 9e29c6389529210978d58cee78e437b901f9daa2 Mon Sep 17 00:00:00 2001
From: Tom Christie <tom@tomchristie.com>
Date: Thu, 10 Oct 2013 17:33:22 +0100
Subject: [PATCH] Ensure read-only fields don't break with current HTML
 renderer behavior

---
 rest_framework/fields.py                      |  3 +++
 rest_framework/serializers.py                 |  2 ++
 rest_framework/tests/test_serializer.py       |  3 +--
 rest_framework/tests/test_serializer_empty.py | 15 +++++++++++++++
 4 files changed, 21 insertions(+), 2 deletions(-)
 create mode 100644 rest_framework/tests/test_serializer_empty.py

diff --git a/rest_framework/fields.py b/rest_framework/fields.py
index 16344d01b..6b039f6c2 100644
--- a/rest_framework/fields.py
+++ b/rest_framework/fields.py
@@ -777,6 +777,7 @@ class IntegerField(WritableField):
     type_name = 'IntegerField'
     type_label = 'integer'
     form_field_class = forms.IntegerField
+    empty = 0
 
     default_error_messages = {
         'invalid': _('Enter a whole number.'),
@@ -808,6 +809,7 @@ class FloatField(WritableField):
     type_name = 'FloatField'
     type_label = 'float'
     form_field_class = forms.FloatField
+    empty = 0
 
     default_error_messages = {
         'invalid': _("'%s' value must be a float."),
@@ -828,6 +830,7 @@ class DecimalField(WritableField):
     type_name = 'DecimalField'
     type_label = 'decimal'
     form_field_class = forms.DecimalField
+    empty = Decimal('0')
 
     default_error_messages = {
         'invalid': _('Enter a number.'),
diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index bc9f73d11..8e9456885 100644
--- a/rest_framework/serializers.py
+++ b/rest_framework/serializers.py
@@ -310,6 +310,8 @@ class BaseSerializer(WritableField):
         ret.fields = self._dict_class()
 
         for field_name, field in self.fields.items():
+            if field.read_only and obj is None:
+               continue
             field.initialize(parent=self, field_name=field_name)
             key = self.get_field_key(field_name)
             value = field.field_to_native(obj, field_name)
diff --git a/rest_framework/tests/test_serializer.py b/rest_framework/tests/test_serializer.py
index 8d246b010..d4e5a93f6 100644
--- a/rest_framework/tests/test_serializer.py
+++ b/rest_framework/tests/test_serializer.py
@@ -159,8 +159,7 @@ class BasicTests(TestCase):
         expected = {
             'email': '',
             'content': '',
-            'created': None,
-            'sub_comment': ''
+            'created': None
         }
         self.assertEqual(serializer.data, expected)
 
diff --git a/rest_framework/tests/test_serializer_empty.py b/rest_framework/tests/test_serializer_empty.py
new file mode 100644
index 000000000..30cff3615
--- /dev/null
+++ b/rest_framework/tests/test_serializer_empty.py
@@ -0,0 +1,15 @@
+from django.test import TestCase
+from rest_framework import serializers
+
+
+class EmptySerializerTestCase(TestCase):
+    def test_empty_serializer(self):
+        class FooBarSerializer(serializers.Serializer):
+            foo = serializers.IntegerField()
+            bar = serializers.SerializerMethodField('get_bar')
+
+            def get_bar(self, obj):
+                return 'bar'
+
+        serializer = FooBarSerializer()
+        self.assertEquals(serializer.data, {'foo': 0})