Fixed #10443 -- Fixed model attribute updating after r10003.

Adding a get_db_prep_save() call to the UpdateQuery code path meant it
was being called twice if you updated an existing model attribute. This
change removes that double call and also makes TimeField.to_python() a
little more robust for the benefit of the Oracle backend (just in case).

git-svn-id: http://code.djangoproject.com/svn/django/trunk@10013 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/base.py

@@ -376,7 +376,7 @@ class Model(object):
                     manager.filter(pk=pk_val).extra(select={'a': 1}).values('a').order_by())):
                 # It does already exist, so do an UPDATE.
                 if force_update or non_pks:
-                    values = [(f, None, f.get_db_prep_save(raw and getattr(self, f.attname) or f.pre_save(self, False))) for f in non_pks]
+                    values = [(f, None, (raw and getattr(self, f.attname) or f.pre_save(self, False))) for f in non_pks]
                     rows = manager.filter(pk=pk_val)._update(values)
                     if force_update and not rows:
                         raise DatabaseError("Forced update did not affect any rows.")

django/db/models/fields/__init__.py

@@ -821,6 +821,11 @@ class TimeField(Field):
             return None
         if isinstance(value, datetime.time):
             return value
+        if isinstance(value, datetime.datetime):
+            # Not usually a good idea to pass in a datetime here (it loses
+            # information), but this can be a side-effect of interacting with a
+            # database backend (e.g. Oracle), so we'll be accommodating.
+            return value.time
 
         # Attempt to parse a datetime:
         value = smart_str(value)

tests/regressiontests/model_regress/models.py

@@ -1,5 +1,9 @@
 # coding: utf-8
+import datetime
+
+from django.conf import settings
 from django.db import models
+from django.utils import tzinfo
 
 CHOICES = (
     (1, 'first'),
@@ -143,5 +147,24 @@ datetime.datetime(2000, 1, 1, 6, 1, 1)
 >>> BrokenUnicodeMethod.objects.all()
 [<BrokenUnicodeMethod: [Bad Unicode data]>]
 
+"""}
+
+if settings.DATABASE_ENGINE != "mysql":
+    __test__["non-mysql-tests"] = """
+# Saving an updating with timezone-aware datetime Python objects. Regression
+# test for #10443.
+
+# The idea is that all these creations and saving should work without crashing.
+# It's not rocket science.
+>>> Article.objects.all().delete()
+>>> dt1 = datetime.datetime(2008, 8, 31, 16, 20, tzinfo=tzinfo.FixedOffset(600))
+>>> dt2 = datetime.datetime(2008, 8, 31, 17, 20, tzinfo=tzinfo.FixedOffset(600))
+>>> obj = Article.objects.create(headline="A headline", pub_date=dt1, article_text="foo")
+
+>>> obj.pub_date = dt2
+>>> obj.save()
+>>> Article.objects.filter(headline="A headline").update(pub_date=dt1)
+1
+
 """
-}
+