Dropped the needs_datetime_string_cast feature.

It has been superseded by the converter infrastructure.

django/db/backends/base/features.py

@@ -7,9 +7,6 @@ class BaseDatabaseFeatures(object):
     gis_enabled = False
     allows_group_by_pk = False
     allows_group_by_selected_pks = False
-    # True if django.db.backends.utils.typecast_timestamp is used on values
-    # returned from dates() calls.
-    needs_datetime_string_cast = True
     empty_fetchmany_value = []
     update_can_self_select = True
 

django/db/backends/oracle/features.py

@@ -9,7 +9,6 @@ except ImportError:
 
 class DatabaseFeatures(BaseDatabaseFeatures):
     empty_fetchmany_value = ()
-    needs_datetime_string_cast = False
     interprets_empty_strings_as_nulls = True
     uses_savepoints = True
     has_select_for_update = True

django/db/backends/postgresql_psycopg2/features.py

@@ -4,7 +4,6 @@ from django.db.utils import InterfaceError
 
 class DatabaseFeatures(BaseDatabaseFeatures):
     allows_group_by_selected_pks = True
-    needs_datetime_string_cast = False
     can_return_id_from_insert = True
     has_real_datatype = True
     has_native_uuid_field = True

docs/releases/1.9.txt

@@ -326,6 +326,8 @@ Database backend API
   fetched from the database is to register a converter for ``DateTimeField``
   in ``DatabaseOperations.get_db_converters()``.
 
+  The ``needs_datetime_string_cast`` database feature was removed. Database
+  backends that set it must register a converter instead, as explained above.
 
 * The ``DatabaseOperations.value_to_db_<type>()`` methods were renamed to
   ``adapt_<type>field_value()`` to mirror the ``convert_<type>field_value()``

tests/timezones/tests.py

@@ -106,7 +106,6 @@ class LegacyDatabaseTests(TestCase):
         self.assertEqual(event.dt.replace(tzinfo=EAT), dt.replace(microsecond=0))
 
     @skipUnlessDBFeature('supports_timezones')
-    @skipIfDBFeature('needs_datetime_string_cast')
     def test_aware_datetime_in_utc(self):
         dt = datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
         Event.objects.create(dt=dt)
@@ -115,24 +114,7 @@ class LegacyDatabaseTests(TestCase):
         # interpret the naive datetime in local time to get the correct value
         self.assertEqual(event.dt.replace(tzinfo=EAT), dt)
 
-    # This combination is no longer possible since timezone support
-    # was removed from the SQLite backend -- it didn't work.
     @skipUnlessDBFeature('supports_timezones')
-    @skipUnlessDBFeature('needs_datetime_string_cast')
-    def test_aware_datetime_in_utc_unsupported(self):
-        dt = datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
-        Event.objects.create(dt=dt)
-        event = Event.objects.get()
-        self.assertIsNone(event.dt.tzinfo)
-        # django.db.backends.utils.typecast_dt will just drop the
-        # timezone, so a round-trip in the database alters the data (!)
-        # interpret the naive datetime in local time and you get a wrong value
-        self.assertNotEqual(event.dt.replace(tzinfo=EAT), dt)
-        # interpret the naive datetime in original time to get the correct value
-        self.assertEqual(event.dt.replace(tzinfo=UTC), dt)
-
-    @skipUnlessDBFeature('supports_timezones')
-    @skipIfDBFeature('needs_datetime_string_cast')
     def test_aware_datetime_in_other_timezone(self):
         dt = datetime.datetime(2011, 9, 1, 17, 20, 30, tzinfo=ICT)
         Event.objects.create(dt=dt)
@@ -141,22 +123,6 @@ class LegacyDatabaseTests(TestCase):
         # interpret the naive datetime in local time to get the correct value
         self.assertEqual(event.dt.replace(tzinfo=EAT), dt)
 
-    # This combination is no longer possible since timezone support
-    # was removed from the SQLite backend -- it didn't work.
-    @skipUnlessDBFeature('supports_timezones')
-    @skipUnlessDBFeature('needs_datetime_string_cast')
-    def test_aware_datetime_in_other_timezone_unsupported(self):
-        dt = datetime.datetime(2011, 9, 1, 17, 20, 30, tzinfo=ICT)
-        Event.objects.create(dt=dt)
-        event = Event.objects.get()
-        self.assertIsNone(event.dt.tzinfo)
-        # django.db.backends.utils.typecast_dt will just drop the
-        # timezone, so a round-trip in the database alters the data (!)
-        # interpret the naive datetime in local time and you get a wrong value
-        self.assertNotEqual(event.dt.replace(tzinfo=EAT), dt)
-        # interpret the naive datetime in original time to get the correct value
-        self.assertEqual(event.dt.replace(tzinfo=ICT), dt)
-
     @skipIfDBFeature('supports_timezones')
     def test_aware_datetime_unspported(self):
         dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)