Fixed #37147 -- Fixed rendering empty values for models with db_default on primary key.

2 files changed, 11 insertions, 1 deletions

diff --git a/django/forms/widgets.py b/django/forms/widgets.py
index f401896b60..56ff7bb5ad 100644
--- a/django/forms/widgets.py
+++ b/django/forms/widgets.py
@@ -343,7 +343,14 @@ class Widget(metaclass=MediaDefiningClass):
         """
         Return a value as it should appear when rendered in a template.
         """
-        if value == "" or value is None:
+        from django.db.models.expressions import DatabaseDefault
+
+        if (
+            value == ""
+            or value is None
+            # Empty value when db_default is used.
+            or isinstance(value, DatabaseDefault)
+        ):
             return None
         if self.is_localized:
             return formats.localize_input(value)
diff --git a/tests/forms_tests/widget_tests/test_widget.py b/tests/forms_tests/widget_tests/test_widget.py
index 9e243570d7..32e5e38f59 100644
--- a/tests/forms_tests/widget_tests/test_widget.py
+++ b/tests/forms_tests/widget_tests/test_widget.py
@@ -1,3 +1,5 @@
+from django.db.models import Value
+from django.db.models.expressions import DatabaseDefault
 from django.forms import Widget
 from django.forms.widgets import Input
 
@@ -9,6 +11,7 @@ class WidgetTests(WidgetTest):
         widget = Widget()
         self.assertIsNone(widget.format_value(None))
         self.assertIsNone(widget.format_value(""))
+        self.assertIsNone(widget.format_value(DatabaseDefault(Value("1"))))
         self.assertEqual(widget.format_value("español"), "español")
         self.assertEqual(widget.format_value(42.5), "42.5")