[1.9.x] Fixed #26215 -- Fixed RangeField/ArrayField serialization with None values

Also added tests for HStoreField and JSONField.
Thanks Aleksey Bukin for the report and Tim Graham for the initial patch and
the review.
Backport of 928c12eb1 from master.

8 files changed, 44 insertions, 11 deletions

diff --git a/django/contrib/postgres/fields/array.py b/django/contrib/postgres/fields/array.py
index 65f28672aa..28e592c7be 100644
--- a/django/contrib/postgres/fields/array.py
+++ b/django/contrib/postgres/fields/array.py
@@ -107,8 +107,11 @@ class ArrayField(Field):
         base_field = self.base_field
 
         for val in vals:
-            obj = AttributeSetter(base_field.attname, val)
-            values.append(base_field.value_to_string(obj))
+            if val is None:
+                values.append(None)
+            else:
+                obj = AttributeSetter(base_field.attname, val)
+                values.append(base_field.value_to_string(obj))
         return json.dumps(values)
 
     def get_transform(self, name):
diff --git a/django/contrib/postgres/fields/ranges.py b/django/contrib/postgres/fields/ranges.py
index bf3f8cb9a4..5bce0743f0 100644
--- a/django/contrib/postgres/fields/ranges.py
+++ b/django/contrib/postgres/fields/ranges.py
@@ -51,8 +51,12 @@ class RangeField(models.Field):
         base_field = self.base_field
         result = {"bounds": value._bounds}
         for end in ('lower', 'upper'):
-            obj = AttributeSetter(base_field.attname, getattr(value, end))
-            result[end] = base_field.value_to_string(obj)
+            val = getattr(value, end)
+            if val is None:
+                result[end] = None
+            else:
+                obj = AttributeSetter(base_field.attname, val)
+                result[end] = base_field.value_to_string(obj)
         return json.dumps(result)
 
     def formfield(self, **kwargs):
diff --git a/docs/releases/1.8.10.txt b/docs/releases/1.8.10.txt
index 4eea5a3b7b..b29000eb20 100644
--- a/docs/releases/1.8.10.txt
+++ b/docs/releases/1.8.10.txt
@@ -17,3 +17,7 @@ Bugfixes
 
 * Made ``forms.FileField`` and ``utils.translation.lazy_number()`` picklable
   (:ticket:`26212`).
+
+* Fixed :class:`~django.contrib.postgres.fields.RangeField` and
+  :class:`~django.contrib.postgres.fields.ArrayField` serialization with
+  ``None`` values (:ticket:`26215`).
diff --git a/docs/releases/1.9.3.txt b/docs/releases/1.9.3.txt
index 05c6542329..af7bcf21bb 100644
--- a/docs/releases/1.9.3.txt
+++ b/docs/releases/1.9.3.txt
@@ -27,3 +27,7 @@ Bugfixes
 
 * Made ``forms.FileField`` and ``utils.translation.lazy_number()`` picklable
   (:ticket:`26212`).
+
+* Fixed :class:`~django.contrib.postgres.fields.RangeField` and
+  :class:`~django.contrib.postgres.fields.ArrayField` serialization with
+  ``None`` values (:ticket:`26215`).
diff --git a/tests/postgres_tests/test_array.py b/tests/postgres_tests/test_array.py
index 094a1e2235..fe9c477d4b 100644
--- a/tests/postgres_tests/test_array.py
+++ b/tests/postgres_tests/test_array.py
@@ -462,17 +462,17 @@ class TestMigrations(TransactionTestCase):
 
 class TestSerialization(PostgreSQLTestCase):
     test_data = (
-        '[{"fields": {"field": "[\\"1\\", \\"2\\"]"}, "model": "postgres_tests.integerarraymodel", "pk": null}]'
+        '[{"fields": {"field": "[\\"1\\", \\"2\\", null]"}, "model": "postgres_tests.integerarraymodel", "pk": null}]'
     )
 
     def test_dumping(self):
-        instance = IntegerArrayModel(field=[1, 2])
+        instance = IntegerArrayModel(field=[1, 2, None])
         data = serializers.serialize('json', [instance])
         self.assertEqual(json.loads(data), json.loads(self.test_data))
 
     def test_loading(self):
         instance = list(serializers.deserialize('json', self.test_data))[0].object
-        self.assertEqual(instance.field, [1, 2])
+        self.assertEqual(instance.field, [1, 2, None])
 
 
 class TestValidation(PostgreSQLTestCase):
diff --git a/tests/postgres_tests/test_hstore.py b/tests/postgres_tests/test_hstore.py
index 68c54918a1..f60f06c855 100644
--- a/tests/postgres_tests/test_hstore.py
+++ b/tests/postgres_tests/test_hstore.py
@@ -140,7 +140,8 @@ class TestQuerying(PostgreSQLTestCase):
 
 
 class TestSerialization(PostgreSQLTestCase):
-    test_data = '[{"fields": {"field": "{\\"a\\": \\"b\\"}"}, "model": "postgres_tests.hstoremodel", "pk": null}]'
+    test_data = ('[{"fields": {"field": "{\\"a\\": \\"b\\"}"}, '
+                 '"model": "postgres_tests.hstoremodel", "pk": null}]')
 
     def test_dumping(self):
         instance = HStoreModel(field={'a': 'b'})
@@ -151,6 +152,12 @@ class TestSerialization(PostgreSQLTestCase):
         instance = list(serializers.deserialize('json', self.test_data))[0].object
         self.assertEqual(instance.field, {'a': 'b'})
 
+    def test_roundtrip_with_null(self):
+        instance = HStoreModel(field={'a': 'b', 'c': None})
+        data = serializers.serialize('json', [instance])
+        new_instance = list(serializers.deserialize('json', data))[0].object
+        self.assertEqual(instance.field, new_instance.field)
+
 
 class TestValidation(PostgreSQLTestCase):
 
diff --git a/tests/postgres_tests/test_json.py b/tests/postgres_tests/test_json.py
index b4f0dd4ecf..59e5fe3fe7 100644
--- a/tests/postgres_tests/test_json.py
+++ b/tests/postgres_tests/test_json.py
@@ -213,16 +213,16 @@ class TestQuerying(TestCase):
 
 @skipUnlessPG94
 class TestSerialization(TestCase):
-    test_data = '[{"fields": {"field": {"a": "b"}}, "model": "postgres_tests.jsonmodel", "pk": null}]'
+    test_data = '[{"fields": {"field": {"a": "b", "c": null}}, "model": "postgres_tests.jsonmodel", "pk": null}]'
 
     def test_dumping(self):
-        instance = JSONModel(field={'a': 'b'})
+        instance = JSONModel(field={'a': 'b', 'c': None})
         data = serializers.serialize('json', [instance])
         self.assertJSONEqual(data, self.test_data)
 
     def test_loading(self):
         instance = list(serializers.deserialize('json', self.test_data))[0].object
-        self.assertEqual(instance.field, {'a': 'b'})
+        self.assertEqual(instance.field, {'a': 'b', 'c': None})
 
 
 class TestValidation(PostgreSQLTestCase):
diff --git a/tests/postgres_tests/test_ranges.py b/tests/postgres_tests/test_ranges.py
index 5620e037b8..7478321245 100644
--- a/tests/postgres_tests/test_ranges.py
+++ b/tests/postgres_tests/test_ranges.py
@@ -323,6 +323,17 @@ class TestSerialization(TestCase):
         self.assertEqual(instance.floats, NumericRange(empty=True))
         self.assertEqual(instance.bigints, None)
 
+    def test_serialize_range_with_null(self):
+        instance = RangesModel(ints=NumericRange(None, 10))
+        data = serializers.serialize('json', [instance])
+        new_instance = list(serializers.deserialize('json', data))[0].object
+        self.assertEqual(new_instance.ints, NumericRange(None, 10))
+
+        instance = RangesModel(ints=NumericRange(10, None))
+        data = serializers.serialize('json', [instance])
+        new_instance = list(serializers.deserialize('json', data))[0].object
+        self.assertEqual(new_instance.ints, NumericRange(10, None))
+
 
 class TestValidators(PostgreSQLTestCase):