Fixed #19560 -- Identified field in warning for naive datetime.

Thanks gcc for the report and vajrasky for the patch.

django/db/models/fields/__init__.py

@@ -998,8 +998,9 @@ class DateTimeField(DateField):
                 # local time. This won't work during DST change, but we can't
                 # do much about it, so we let the exceptions percolate up the
                 # call stack.
-                warnings.warn("DateTimeField received a naive datetime (%s)"
-                              " while time zone support is active." % value,
+                warnings.warn("DateTimeField %s.%s received a naive datetime "
+                              "(%s) while time zone support is active." %
+                              (self.model.__name__, self.name, value),
                               RuntimeWarning)
                 default_timezone = timezone.get_default_timezone()
                 value = timezone.make_aware(value, default_timezone)
@@ -1053,8 +1054,9 @@ class DateTimeField(DateField):
             # For backwards compatibility, interpret naive datetimes in local
             # time. This won't work during DST change, but we can't do much
             # about it, so we let the exceptions percolate up the call stack.
-            warnings.warn("DateTimeField received a naive datetime (%s)"
-                          " while time zone support is active." % value,
+            warnings.warn("DateTimeField %s.%s received a naive datetime (%s)"
+                          " while time zone support is active." %
+                          (self.model.__name__, self.name, value),
                           RuntimeWarning)
             default_timezone = timezone.get_default_timezone()
             value = timezone.make_aware(value, default_timezone)

docs/topics/i18n/timezones.txt

@@ -431,14 +431,15 @@ code: :func:`~django.utils.timezone.now`,
 Finally, in order to help you locate code that needs upgrading, Django raises
 a warning when you attempt to save a naive datetime to the database::
 
-    RuntimeWarning: DateTimeField received a naive datetime (2012-01-01 00:00:00) while time zone support is active.
+    RuntimeWarning: DateTimeField ModelName.field_name received a naive
+    datetime (2012-01-01 00:00:00) while time zone support is active.
 
 During development, you can turn such warnings into exceptions and get a
 traceback by adding the following to your settings file::
 
     import warnings
     warnings.filterwarnings(
-            'error', r"DateTimeField received a naive datetime",
+            'error', r"DateTimeField .* received a naive datetime",
             RuntimeWarning, r'django\.db\.models\.fields')
 
 Fixtures

tests/timezones/tests.py

@@ -274,7 +274,8 @@ class NewDatabaseTests(TestCase):
             Event.objects.create(dt=dt)
             self.assertEqual(len(recorded), 1)
             msg = str(recorded[0].message)
-            self.assertTrue(msg.startswith("DateTimeField received a naive datetime"))
+            self.assertTrue(msg.startswith("DateTimeField Event.dt received "
+                                           "a naive datetime"))
         event = Event.objects.get()
         # naive datetimes are interpreted in local time
         self.assertEqual(event.dt, dt.replace(tzinfo=EAT))
@@ -287,7 +288,8 @@ class NewDatabaseTests(TestCase):
             Event.objects.create(dt=dt)
             self.assertEqual(len(recorded), 1)
             msg = str(recorded[0].message)
-            self.assertTrue(msg.startswith("DateTimeField received a naive datetime"))
+            self.assertTrue(msg.startswith("DateTimeField Event.dt received "
+                                           "a naive datetime"))
         event = Event.objects.get()
         self.assertEqual(event.dt, datetime.datetime(2011, 9, 1, tzinfo=EAT))
 
@@ -300,7 +302,8 @@ class NewDatabaseTests(TestCase):
             Event.objects.create(dt=dt)
             self.assertEqual(len(recorded), 1)
             msg = str(recorded[0].message)
-            self.assertTrue(msg.startswith("DateTimeField received a naive datetime"))
+            self.assertTrue(msg.startswith("DateTimeField Event.dt received "
+                                           "a naive datetime"))
         event = Event.objects.get()
         # naive datetimes are interpreted in local time
         self.assertEqual(event.dt, dt.replace(tzinfo=EAT))
@@ -314,7 +317,8 @@ class NewDatabaseTests(TestCase):
             Event.objects.create(dt=dt)
             self.assertEqual(len(recorded), 1)
             msg = str(recorded[0].message)
-            self.assertTrue(msg.startswith("DateTimeField received a naive datetime"))
+            self.assertTrue(msg.startswith("DateTimeField Event.dt received "
+                                           "a naive datetime"))
         event = Event.objects.get()
         # microseconds are lost during a round-trip in the database
         # naive datetimes are interpreted in local time
@@ -401,7 +405,8 @@ class NewDatabaseTests(TestCase):
             self.assertEqual(len(recorded), 3)
             for warning in recorded:
                 msg = str(warning.message)
-                self.assertTrue(msg.startswith("DateTimeField received a naive datetime"))
+                self.assertTrue(msg.startswith("DateTimeField Event.dt "
+                                               "received a naive datetime"))
 
     @skipUnlessDBFeature('has_zoneinfo_database')
     def test_query_datetime_lookups(self):