Fixed #25233 -- Fixed HStoreField.has_changed() handling of initial values.

Thanks Simon Charette for review.

1 files changed, 8 insertions, 7 deletions

diff --git a/django/contrib/postgres/forms/hstore.py b/django/contrib/postgres/forms/hstore.py
index 3dc70ab2ab..bf562c0e8f 100644
--- a/django/contrib/postgres/forms/hstore.py
+++ b/django/contrib/postgres/forms/hstore.py
@@ -23,13 +23,14 @@ class HStoreField(forms.CharField):
     def to_python(self, value):
         if not value:
             return {}
-        try:
-            value = json.loads(value)
-        except ValueError:
-            raise ValidationError(
-                self.error_messages['invalid_json'],
-                code='invalid_json',
-            )
+        if not isinstance(value, dict):
+            try:
+                value = json.loads(value)
+            except ValueError:
+                raise ValidationError(
+                    self.error_messages['invalid_json'],
+                    code='invalid_json',
+                )
         # Cast everything to strings for ease.
         for key, val in value.items():
             value[key] = six.text_type(val)