Name conflict if tracked model has field named "instance"

AUTHORS.rst

@@ -107,3 +107,4 @@
 | Nafees Anwar <h.nafees.anwar@gmail.com>
 | meanmail <github@meanmail.dev>
 | Nicholas Prat <nprat96@gmail.com>
+| Boris Shemigon <i@boris.co>

model_utils/tracker.py

@@ -398,9 +398,9 @@ def patch_init(self, model: type[models.Model]) -> None:
         original = getattr(model, '__init__')
 
         @wraps(original)
-        def inner(instance: models.Model, *args: Any, **kwargs: Any) -> None:
-            original(instance, *args, **kwargs)
-            self.initialize_tracker(model, instance)
+        def inner(*args: Any, **kwargs: Any) -> None:
+            original(*args, **kwargs)
+            self.initialize_tracker(model, args[0])
 
         setattr(model, '__init__', inner)
 

tests/models.py

@@ -349,6 +349,13 @@ class ModelTrackedMultiple(models.Model):
     number_tracker = ModelTracker(fields=['number'])
 
 
+class TrackedModelWithSpecialNamedField(models.Model):
+    instance = models.CharField(max_length=20)
+    name = models.CharField(max_length=20)
+
+    tracker = FieldTracker()
+
+
 class InheritedModelTracked(ModelTracked):
     name2 = models.CharField(max_length=20)
 

tests/test_models/test_special_name_field_model.py

@@ -0,0 +1,19 @@
+from __future__ import annotations
+
+from django.test import TestCase
+
+from tests.models import TrackedModelWithSpecialNamedField
+
+
+class SpecialNamedFieldTests(TestCase):
+    def test_model_with_instance_field(self) -> None:
+        t = TrackedModelWithSpecialNamedField.objects.create(
+            instance="45.55",
+            name="test",
+        )
+        self.assertEqual(t.instance, "45.55")
+
+        t.instance = "56.78"
+        t.save()
+
+        t.delete()

tests/test_models/test_timeframed_model.py

@@ -1,10 +1,11 @@
 from __future__ import annotations
 
-from datetime import datetime, timedelta
+from datetime import timedelta
 
 from django.core.exceptions import ImproperlyConfigured
 from django.db import models
 from django.test import TestCase
+from django.utils.timezone import now
 
 from model_utils.managers import QueryManager
 from model_utils.models import TimeFramedModel
@@ -13,7 +14,7 @@
 
 class TimeFramedModelTests(TestCase):
     def setUp(self) -> None:
-        self.now = datetime.now()
+        self.now = now()
 
     def test_not_yet_begun(self) -> None:
         TimeFrame.objects.create(start=self.now + timedelta(days=2))

tests/test_models/test_timestamped_model.py

@@ -5,6 +5,7 @@
 
 import time_machine
 from django.test import TestCase
+from django.utils.timezone import now
 
 from tests.models import TimeStamp, TimeStampWithStatusModel
 
@@ -36,7 +37,7 @@ def test_overriding_created_via_object_creation_also_uses_creation_date_for_modi
         Setting the created date when first creating an object
         should be permissible.
         """
-        different_date = datetime.today() - timedelta(weeks=52)
+        different_date = now() - timedelta(weeks=52)
         t1 = TimeStamp.objects.create(created=different_date)
         self.assertEqual(t1.created, different_date)
         self.assertEqual(t1.modified, different_date)
@@ -46,7 +47,7 @@ def test_overriding_modified_via_object_creation(self) -> None:
         Setting the modified date explicitly should be possible when
         first creating an object, but not thereafter.
         """
-        different_date = datetime.today() - timedelta(weeks=52)
+        different_date = now() - timedelta(weeks=52)
         t1 = TimeStamp.objects.create(modified=different_date)
         self.assertEqual(t1.modified, different_date)
         self.assertNotEqual(t1.created, different_date)
@@ -56,7 +57,7 @@ def test_overriding_created_after_object_created(self) -> None:
         The created date may be changed post-create
         """
         t1 = TimeStamp.objects.create()
-        different_date = datetime.today() - timedelta(weeks=52)
+        different_date = now() - timedelta(weeks=52)
         t1.created = different_date
         t1.save()
         self.assertEqual(t1.created, different_date)
@@ -67,7 +68,7 @@ def test_overriding_modified_after_object_created(self) -> None:
         is saved, regardless of attempts to change it.
         """
         t1 = TimeStamp.objects.create()
-        different_date = datetime.today() - timedelta(weeks=52)
+        different_date = now() - timedelta(weeks=52)
         t1.modified = different_date
         t1.save()
         self.assertNotEqual(t1.modified, different_date)
@@ -79,13 +80,13 @@ def test_overrides_using_save(self) -> None:
         After that, only created may be modified manually.
         """
         t1 = TimeStamp()
-        different_date = datetime.today() - timedelta(weeks=52)
+        different_date = now() - timedelta(weeks=52)
         t1.created = different_date
         t1.modified = different_date
         t1.save()
         self.assertEqual(t1.created, different_date)
         self.assertEqual(t1.modified, different_date)
-        different_date2 = datetime.today() - timedelta(weeks=26)
+        different_date2 = now() - timedelta(weeks=26)
         t1.created = different_date2
         t1.modified = different_date2
         t1.save()