Fixed #25532 -- Properly redisplayed JSONField form input values

Thanks David Szotten for the report and Tommy Beadle for code inspiration.
Thanks Tim Graham for the review.

1 files changed, 15 insertions, 0 deletions

diff --git a/django/contrib/postgres/forms/jsonb.py b/django/contrib/postgres/forms/jsonb.py
index 8eefc14993..415288dc90 100644
--- a/django/contrib/postgres/forms/jsonb.py
+++ b/django/contrib/postgres/forms/jsonb.py
@@ -1,11 +1,16 @@
 import json
 
 from django import forms
+from django.utils import six
 from django.utils.translation import ugettext_lazy as _
 
 __all__ = ['JSONField']
 
 
+class InvalidJSONInput(six.text_type):
+    pass
+
+
 class JSONField(forms.CharField):
     default_error_messages = {
         'invalid': _("'%(value)s' value must be valid JSON."),
@@ -27,5 +32,15 @@ class JSONField(forms.CharField):
                 params={'value': value},
             )
 
+    def bound_data(self, data, initial):
+        if self.disabled:
+            return initial
+        try:
+            return json.loads(data)
+        except ValueError:
+            return InvalidJSONInput(data)
+
     def prepare_value(self, value):
+        if isinstance(value, InvalidJSONInput):
+            return value
         return json.dumps(value)