[1.10.x] Fixed #26949 -- Fixed crash of disabled forms.JSONField.

Backport of 68de48c96328e13d5dbdb1f3006e4a1ca74f3c34 from master

2 files changed, 10 insertions, 0 deletions

diff --git a/django/contrib/postgres/forms/jsonb.py b/django/contrib/postgres/forms/jsonb.py
index 415288dc90..df2504cc98 100644
--- a/django/contrib/postgres/forms/jsonb.py
+++ b/django/contrib/postgres/forms/jsonb.py
@@ -21,6 +21,8 @@ class JSONField(forms.CharField):
         super(JSONField, self).__init__(**kwargs)
 
     def to_python(self, value):
+        if self.disabled:
+            return value
         if value in self.empty_values:
             return None
         try:
diff --git a/tests/postgres_tests/test_json.py b/tests/postgres_tests/test_json.py
index d4f0a9bb57..1978552cf9 100644
--- a/tests/postgres_tests/test_json.py
+++ b/tests/postgres_tests/test_json.py
@@ -260,6 +260,14 @@ class TestFormField(PostgreSQLTestCase):
         form_field = model_field.formfield()
         self.assertIsInstance(form_field, forms.JSONField)
 
+    def test_formfield_disabled(self):
+        class JsonForm(Form):
+            name = CharField()
+            jfield = forms.JSONField(disabled=True)
+
+        form = JsonForm({'name': 'xyz', 'jfield': '["bar"]'}, initial={'jfield': ['foo']})
+        self.assertIn('[&quot;foo&quot;]</textarea>', form.as_p())
+
     def test_prepare_value(self):
         field = forms.JSONField()
         self.assertEqual(field.prepare_value({'a': 'b'}), '{"a": "b"}')