Add json util wrapper, failing JSONField test

rest_framework/utils/encoders.py

 """
 Helper classes for parsers.
 """
-from __future__ import unicode_literals
+from __future__ import absolute_import, unicode_literals
 
 import datetime
 import decimal

rest_framework/utils/json.py

+
+from __future__ import absolute_import
+
+import functools
+import json
+
+
+def strict_constant(o):
+    raise ValueError('Out of range float values are not JSON compliant: ' + repr(o))
+
+
+@functools.wraps(json.dump)
+def dump(*args, **kwargs):
+    kwargs.setdefault('allow_nan', False)
+    return json.dump(*args, **kwargs)
+
+
+@functools.wraps(json.dumps)
+def dumps(*args, **kwargs):
+    kwargs.setdefault('allow_nan', False)
+    return json.dumps(*args, **kwargs)
+
+
+@functools.wraps(json.load)
+def load(*args, **kwargs):
+    kwargs.setdefault('parse_constant', strict_constant)
+    return json.load(*args, **kwargs)
+
+
+@functools.wraps(json.loads)
+def loads(*args, **kwargs):
+    kwargs.setdefault('parse_constant', strict_constant)
+    return json.loads(*args, **kwargs)

tests/test_fields.py

@@ -1896,6 +1896,7 @@ class TestJSONField(FieldValues):
     ]
     invalid_inputs = [
         ({'a': set()}, ['Value must be valid JSON.']),
+        ({'a': float('inf')}, ['Value must be valid JSON.']),
     ]
     outputs = [
         ({

tests/test_utils.py

@@ -9,6 +9,7 @@ import rest_framework.utils.model_meta
 from rest_framework.compat import _resolve_model
 from rest_framework.routers import SimpleRouter
 from rest_framework.serializers import ModelSerializer
+from rest_framework.utils import json
 from rest_framework.utils.breadcrumbs import get_breadcrumbs
 from rest_framework.views import APIView
 from rest_framework.viewsets import ModelViewSet
@@ -177,3 +178,23 @@ class ResolveModelWithPatchedDjangoTests(TestCase):
     def test_blows_up_if_model_does_not_resolve(self):
         with self.assertRaises(ImproperlyConfigured):
             _resolve_model('tests.BasicModel')
+
+
+class JsonFloatTests(TestCase):
+    """
+    Internaly, wrapped json functions should adhere to strict float handling
+    """
+
+    def test_dumps(self):
+        with self.assertRaises(ValueError):
+            json.dumps(float('inf'))
+
+        with self.assertRaises(ValueError):
+            json.dumps(float('nan'))
+
+    def test_loads(self):
+        with self.assertRaises(ValueError):
+            json.loads("Infinity")
+
+        with self.assertRaises(ValueError):
+            json.loads("NaN")