Added another test.

rest_framework/tests/test_serializer_nested.py

@@ -6,9 +6,45 @@ Doesn't cover model serializers.
 from __future__ import unicode_literals
 from django.test import TestCase
 from rest_framework import serializers
+from rest_framework.serializers import BATCH_ADD, BATCH_UPDATE, BATCH_DELETE
 from . import models
 
 
+class BlogPostCommentSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = models.BlogPostComment
+        fields = ('id', 'text')
+
+
+class BlogPostSerializer(serializers.ModelSerializer):
+    comments = BlogPostCommentSerializer(many=True, source='blogpostcomment_set')
+    class Meta:
+        model = models.BlogPost
+        fields = ('id', 'title', 'comments')
+
+
+class PersonSerializer(serializers.ModelSerializer):
+    posts = BlogPostSerializer(many=True, source='blogpost_set')
+    class Meta:
+        model = models.Person
+        fields = ('id', 'name', 'age', 'posts')
+
+
+class BlogPostCreateSerializer(serializers.ModelSerializer):
+    comments = BlogPostCommentSerializer(many=True,
+        source='blogpostcomment_set', batch_mode=BATCH_ADD | BATCH_UPDATE)
+    class Meta:
+        model = models.BlogPost
+        fields = ('id', 'title', 'comments')
+
+class BlogPostDeleteSerializer(serializers.ModelSerializer):
+    comments = BlogPostCommentSerializer(many=True,
+        source='blogpostcomment_set', batch_mode=BATCH_ADD | BATCH_UPDATE)
+    class Meta:
+        model = models.BlogPost
+        fields = ('id', 'title', 'comments')
+
+
 class WritableNestedSerializerBasicTests(TestCase):
     """
     Tests for deserializing nested entities.
@@ -316,32 +352,68 @@ class ForeignKeyNestedSerializerUpdateTests(TestCase):
 
 class NestedModelSerializerUpdateTests(TestCase):
     def test_second_nested_level(self):
+        """
+        Make sure we can span relations for nested representations
+        """
         john = models.Person.objects.create(name="john")
 
         post = john.blogpost_set.create(title="Test blog post")
         post.blogpostcomment_set.create(text="I hate this blog post")
         post.blogpostcomment_set.create(text="I love this blog post")
 
-        class BlogPostCommentSerializer(serializers.ModelSerializer):
-            class Meta:
-                model = models.BlogPostComment
-
-        class BlogPostSerializer(serializers.ModelSerializer):
-            comments = BlogPostCommentSerializer(many=True, source='blogpostcomment_set')
-            class Meta:
-                model = models.BlogPost
-                fields = ('id', 'title', 'comments')
-
-        class PersonSerializer(serializers.ModelSerializer):
-            posts = BlogPostSerializer(many=True, source='blogpost_set')
-            class Meta:
-                model = models.Person
-                fields = ('id', 'name', 'age', 'posts')
-
         serialize = PersonSerializer(instance=john)
         deserialize = PersonSerializer(data=serialize.data, instance=john)
-        self.assertTrue(deserialize.is_valid())
+        self.assertTrue(deserialize.is_valid(), deserialize.errors)
 
         result = deserialize.object
         result.save()
         self.assertEqual(result.id, john.id)
+
+    def test_nested_creation_in_update_only_mode(self):
+        """
+        Create nested 
+        """
+        post = models.BlogPost(title='Test blog post')
+        post.save()
+        data = {
+            'title': 'Test blog post',
+            'comments': [{
+                    'text': 'I hate this blog post',
+                }, {
+                    'text': 'I love this blog post',
+            }],
+        }
+
+        serializer = BlogPostSerializer(data=data, instance=post)
+        self.assertFalse(serializer.is_valid())
+        self.assertEqual(serializer.errors, {
+            u'comments': [{
+                u'non_field_errors': [u'Cannot create a new item, only existing items may be updated.']
+            }, {
+                u'non_field_errors': [u'Cannot create a new item, only existing items may be updated.']
+            }]
+        })
+
+    def test_updates_in_creation_mode(self):
+        """
+        Create nested 
+        """
+        post = models.BlogPost(title='Test blog post')
+        post.save()
+        post.blogpostcomment_set.create(text="This should remain.")
+        data = {
+            'id': post.id,
+            'title': 'Test blog post',
+            'comments': [{
+                    'text': 'I hate this blog post',
+                }, {
+                    'text': 'I love this blog post',
+            }],
+        }
+
+        serializer = BlogPostCreateSerializer(data=data, instance=post)
+        self.assertTrue(serializer.is_valid(), serializer.errors)
+        post = serializer.save()
+        self.assertTrue(post.id)
+        self.assertEqual(post.blogpostcomment_set.count(), 3)
+