Fix Expression test compatibility for Django 6.0+ (#759)

* Skip incompatible tests on Django 6.0+

refs:
- #635
- #646
- https://code.djangoproject.com/ticket/27222

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* remove skipif

* Add changelog

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -5,6 +5,7 @@
 #### Improvements
 
 - feat: Add audit log history view to Django Admin. ([#743](https://github.com/jazzband/django-auditlog/pull/743))
+- Fix Expression test compatibility for Django 6.0+ ([#759](https://github.com/jazzband/django-auditlog/pull/759))
 
 ## 3.2.1 (2025-07-03)
 

auditlog_tests/tests.py

@@ -9,6 +9,7 @@ from unittest.mock import patch
 
 import freezegun
 from dateutil.tz import gettz
+from django import VERSION as DJANGO_VERSION
 from django.apps import apps
 from django.conf import settings
 from django.contrib.admin.sites import AdminSite
@@ -1229,15 +1230,30 @@ class DateTimeFieldModelTest(TestCase):
         dtm.naive_dt = Now()
         self.assertEqual(dtm.naive_dt, Now())
         dtm.save()
-        self.assertEqual(dtm.naive_dt, Now())
+
+        # Django 6.0+ evaluates expressions during save (django ticket #27222)
+        if DJANGO_VERSION >= (6, 0, 0):
+            with self.subTest("After save Django 6.0+"):
+                self.assertIsInstance(dtm.naive_dt, datetime.datetime)
+        else:
+            with self.subTest("After save Django < 6.0"):
+                self.assertEqual(dtm.naive_dt, Now())
 
     def test_json_field_value_none(self):
         json_model = NullableJSONModel(json=Value(None, JSONField()))
         json_model.save()
         self.assertEqual(json_model.history.count(), 1)
-        self.assertEqual(
-            json_model.history.latest().changes_dict["json"][1], "Value(None)"
-        )
+        changes_dict = json_model.history.latest().changes_dict
+
+        # Django 6.0+ evaluates expressions during save (django ticket #27222)
+        if DJANGO_VERSION >= (6, 0, 0):
+            with self.subTest("Django 6.0+"):
+                # Value(None) gets evaluated to "null"
+                self.assertEqual(changes_dict["json"][1], "null")
+        else:
+            with self.subTest("Django < 6.0"):
+                # Value(None) is preserved as string representation
+                self.assertEqual(changes_dict["json"][1], "Value(None)")
 
 
 class UnregisterTest(TestCase):