django/tests/timezones/tests.py

import datetime
import re
import sys
from contextlib import contextmanager
from unittest import SkipTest, skipIf
from xml.dom.minidom import parseString

try:
    import zoneinfo
except ImportError:
    from backports import zoneinfo

try:
    import pytz
except ImportError:
    pytz = None

from django.contrib.auth.models import User
from django.core import serializers
from django.db import connection
from django.db.models import F, Max, Min
from django.http import HttpRequest
from django.template import (
    Context,
    RequestContext,
    Template,
    TemplateSyntaxError,
    context_processors,
)
from django.test import (
    SimpleTestCase,
    TestCase,
    TransactionTestCase,
    ignore_warnings,
    override_settings,
    skipIfDBFeature,
    skipUnlessDBFeature,
)
from django.test.utils import requires_tz_support
from django.urls import reverse
from django.utils import timezone
from django.utils.deprecation import RemovedInDjango50Warning
from django.utils.timezone import timedelta

from .forms import (
    EventForm,
    EventLocalizedForm,
    EventLocalizedModelForm,
    EventModelForm,
    EventSplitForm,
)
from .models import (
    AllDayEvent,
    DailyEvent,
    Event,
    MaybeEvent,
    Session,
    SessionEvent,
    Timestamp,
)

try:
    import yaml

    HAS_YAML = True
except ImportError:
    HAS_YAML = False

# These tests use the EAT (Eastern Africa Time) and ICT (Indochina Time)
# who don't have daylight saving time, so we can represent them easily
# with fixed offset timezones and use them directly as tzinfo in the
# constructors.

# settings.TIME_ZONE is forced to EAT. Most tests use a variant of
# datetime.datetime(2011, 9, 1, 13, 20, 30), which translates to
# 10:20:30 in UTC and 17:20:30 in ICT.

UTC = timezone.utc
EAT = timezone.get_fixed_timezone(180)  # Africa/Nairobi
ICT = timezone.get_fixed_timezone(420)  # Asia/Bangkok

ZONE_CONSTRUCTORS = (zoneinfo.ZoneInfo,)
if pytz is not None:
    ZONE_CONSTRUCTORS += (pytz.timezone,)


def get_timezones(key):
    return [constructor(key) for constructor in ZONE_CONSTRUCTORS]


@contextmanager
def override_database_connection_timezone(timezone):
    try:
        orig_timezone = connection.settings_dict["TIME_ZONE"]
        connection.settings_dict["TIME_ZONE"] = timezone
        # Clear cached properties, after first accessing them to ensure they exist.
        connection.timezone
        del connection.timezone
        connection.timezone_name
        del connection.timezone_name
        yield
    finally:
        connection.settings_dict["TIME_ZONE"] = orig_timezone
        # Clear cached properties, after first accessing them to ensure they exist.
        connection.timezone
        del connection.timezone
        connection.timezone_name
        del connection.timezone_name


@override_settings(TIME_ZONE="Africa/Nairobi", USE_TZ=False)
class LegacyDatabaseTests(TestCase):
    def test_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    def test_naive_datetime_with_microsecond(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, 405060)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    @skipUnlessDBFeature("supports_timezones")
    def test_aware_datetime_in_local_timezone(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertIsNone(event.dt.tzinfo)
        # interpret the naive datetime in local time to get the correct value
        self.assertEqual(event.dt.replace(tzinfo=EAT), dt)

    @skipUnlessDBFeature("supports_timezones")
    def test_aware_datetime_in_local_timezone_with_microsecond(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, 405060, tzinfo=EAT)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertIsNone(event.dt.tzinfo)
        # interpret the naive datetime in local time to get the correct value
        self.assertEqual(event.dt.replace(tzinfo=EAT), dt)

    @skipUnlessDBFeature("supports_timezones")
    def test_aware_datetime_in_utc(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)
        # interpret the naive datetime in local time to get the correct value
        self.assertEqual(event.dt.replace(tzinfo=EAT), dt)

    @skipUnlessDBFeature("supports_timezones")
    def test_aware_datetime_in_other_timezone(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)
        # interpret the naive datetime in local time to get the correct value
        self.assertEqual(event.dt.replace(tzinfo=EAT), dt)

    @skipIfDBFeature("supports_timezones")
    def test_aware_datetime_unsupported(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        msg = "backend does not support timezone-aware datetimes when USE_TZ is False."
        with self.assertRaisesMessage(ValueError, msg):
            Event.objects.create(dt=dt)

    def test_auto_now_and_auto_now_add(self):
        now = datetime.datetime.now()
        past = now - datetime.timedelta(seconds=2)
        future = now + datetime.timedelta(seconds=2)
        Timestamp.objects.create()
        ts = Timestamp.objects.get()
        self.assertLess(past, ts.created)
        self.assertLess(past, ts.updated)
        self.assertGreater(future, ts.updated)
        self.assertGreater(future, ts.updated)

    def test_query_filter(self):
        dt1 = datetime.datetime(2011, 9, 1, 12, 20, 30)
        dt2 = datetime.datetime(2011, 9, 1, 14, 20, 30)
        Event.objects.create(dt=dt1)
        Event.objects.create(dt=dt2)
        self.assertEqual(Event.objects.filter(dt__gte=dt1).count(), 2)
        self.assertEqual(Event.objects.filter(dt__gt=dt1).count(), 1)
        self.assertEqual(Event.objects.filter(dt__gte=dt2).count(), 1)
        self.assertEqual(Event.objects.filter(dt__gt=dt2).count(), 0)

    def test_query_datetime_lookups(self):
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 1, 30, 0))
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 4, 30, 0))
        self.assertEqual(Event.objects.filter(dt__year=2011).count(), 2)
        self.assertEqual(Event.objects.filter(dt__month=1).count(), 2)
        self.assertEqual(Event.objects.filter(dt__day=1).count(), 2)
        self.assertEqual(Event.objects.filter(dt__week_day=7).count(), 2)
        self.assertEqual(Event.objects.filter(dt__iso_week_day=6).count(), 2)
        self.assertEqual(Event.objects.filter(dt__hour=1).count(), 1)
        self.assertEqual(Event.objects.filter(dt__minute=30).count(), 2)
        self.assertEqual(Event.objects.filter(dt__second=0).count(), 2)

    def test_query_aggregation(self):
        # Only min and max make sense for datetimes.
        Event.objects.create(dt=datetime.datetime(2011, 9, 1, 23, 20, 20))
        Event.objects.create(dt=datetime.datetime(2011, 9, 1, 13, 20, 30))
        Event.objects.create(dt=datetime.datetime(2011, 9, 1, 3, 20, 40))
        result = Event.objects.aggregate(Min("dt"), Max("dt"))
        self.assertEqual(
            result,
            {
                "dt__min": datetime.datetime(2011, 9, 1, 3, 20, 40),
                "dt__max": datetime.datetime(2011, 9, 1, 23, 20, 20),
            },
        )

    def test_query_annotation(self):
        # Only min and max make sense for datetimes.
        morning = Session.objects.create(name="morning")
        afternoon = Session.objects.create(name="afternoon")
        SessionEvent.objects.create(
            dt=datetime.datetime(2011, 9, 1, 23, 20, 20), session=afternoon
        )
        SessionEvent.objects.create(
            dt=datetime.datetime(2011, 9, 1, 13, 20, 30), session=afternoon
        )
        SessionEvent.objects.create(
            dt=datetime.datetime(2011, 9, 1, 3, 20, 40), session=morning
        )
        morning_min_dt = datetime.datetime(2011, 9, 1, 3, 20, 40)
        afternoon_min_dt = datetime.datetime(2011, 9, 1, 13, 20, 30)
        self.assertQuerysetEqual(
            Session.objects.annotate(dt=Min("events__dt")).order_by("dt"),
            [morning_min_dt, afternoon_min_dt],
            transform=lambda d: d.dt,
        )
        self.assertQuerysetEqual(
            Session.objects.annotate(dt=Min("events__dt")).filter(
                dt__lt=afternoon_min_dt
            ),
            [morning_min_dt],
            transform=lambda d: d.dt,
        )
        self.assertQuerysetEqual(
            Session.objects.annotate(dt=Min("events__dt")).filter(
                dt__gte=afternoon_min_dt
            ),
            [afternoon_min_dt],
            transform=lambda d: d.dt,
        )

    def test_query_datetimes(self):
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 1, 30, 0))
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 4, 30, 0))
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "year"),
            [datetime.datetime(2011, 1, 1, 0, 0, 0)],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "month"),
            [datetime.datetime(2011, 1, 1, 0, 0, 0)],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "day"),
            [datetime.datetime(2011, 1, 1, 0, 0, 0)],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "hour"),
            [
                datetime.datetime(2011, 1, 1, 1, 0, 0),
                datetime.datetime(2011, 1, 1, 4, 0, 0),
            ],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "minute"),
            [
                datetime.datetime(2011, 1, 1, 1, 30, 0),
                datetime.datetime(2011, 1, 1, 4, 30, 0),
            ],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "second"),
            [
                datetime.datetime(2011, 1, 1, 1, 30, 0),
                datetime.datetime(2011, 1, 1, 4, 30, 0),
            ],
        )

    def test_raw_sql(self):
        # Regression test for #17755
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30)
        event = Event.objects.create(dt=dt)
        self.assertEqual(
            list(
                Event.objects.raw("SELECT * FROM timezones_event WHERE dt = %s", [dt])
            ),
            [event],
        )

    def test_cursor_execute_accepts_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30)
        with connection.cursor() as cursor:
            cursor.execute("INSERT INTO timezones_event (dt) VALUES (%s)", [dt])
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    def test_cursor_execute_returns_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30)
        Event.objects.create(dt=dt)
        with connection.cursor() as cursor:
            cursor.execute("SELECT dt FROM timezones_event WHERE dt = %s", [dt])
            self.assertEqual(cursor.fetchall()[0][0], dt)

    def test_filter_date_field_with_aware_datetime(self):
        # Regression test for #17742
        day = datetime.date(2011, 9, 1)
        AllDayEvent.objects.create(day=day)
        # This is 2011-09-02T01:30:00+03:00 in EAT
        dt = datetime.datetime(2011, 9, 1, 22, 30, 0, tzinfo=UTC)
        self.assertTrue(AllDayEvent.objects.filter(day__gte=dt).exists())


@override_settings(TIME_ZONE="Africa/Nairobi", USE_TZ=True)
class NewDatabaseTests(TestCase):
    naive_warning = "DateTimeField Event.dt received a naive datetime"

    @skipIfDBFeature("supports_timezones")
    def test_aware_time_unsupported(self):
        t = datetime.time(13, 20, 30, tzinfo=EAT)
        msg = "backend does not support timezone-aware times."
        with self.assertRaisesMessage(ValueError, msg):
            DailyEvent.objects.create(time=t)

    @requires_tz_support
    def test_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30)
        with self.assertWarnsMessage(RuntimeWarning, self.naive_warning):
            Event.objects.create(dt=dt)
        event = Event.objects.get()
        # naive datetimes are interpreted in local time
        self.assertEqual(event.dt, dt.replace(tzinfo=EAT))

    @requires_tz_support
    def test_datetime_from_date(self):
        dt = datetime.date(2011, 9, 1)
        with self.assertWarnsMessage(RuntimeWarning, self.naive_warning):
            Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertEqual(event.dt, datetime.datetime(2011, 9, 1, tzinfo=EAT))

    @requires_tz_support
    def test_naive_datetime_with_microsecond(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, 405060)
        with self.assertWarnsMessage(RuntimeWarning, self.naive_warning):
            Event.objects.create(dt=dt)
        event = Event.objects.get()
        # naive datetimes are interpreted in local time
        self.assertEqual(event.dt, dt.replace(tzinfo=EAT))

    def test_aware_datetime_in_local_timezone(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    def test_aware_datetime_in_local_timezone_with_microsecond(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, 405060, tzinfo=EAT)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    def test_aware_datetime_in_utc(self):
        dt = datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    def test_aware_datetime_in_other_timezone(self):
        dt = datetime.datetime(2011, 9, 1, 17, 20, 30, tzinfo=ICT)
        Event.objects.create(dt=dt)
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    def test_auto_now_and_auto_now_add(self):
        now = timezone.now()
        past = now - datetime.timedelta(seconds=2)
        future = now + datetime.timedelta(seconds=2)
        Timestamp.objects.create()
        ts = Timestamp.objects.get()
        self.assertLess(past, ts.created)
        self.assertLess(past, ts.updated)
        self.assertGreater(future, ts.updated)
        self.assertGreater(future, ts.updated)

    def test_query_filter(self):
        dt1 = datetime.datetime(2011, 9, 1, 12, 20, 30, tzinfo=EAT)
        dt2 = datetime.datetime(2011, 9, 1, 14, 20, 30, tzinfo=EAT)
        Event.objects.create(dt=dt1)
        Event.objects.create(dt=dt2)
        self.assertEqual(Event.objects.filter(dt__gte=dt1).count(), 2)
        self.assertEqual(Event.objects.filter(dt__gt=dt1).count(), 1)
        self.assertEqual(Event.objects.filter(dt__gte=dt2).count(), 1)
        self.assertEqual(Event.objects.filter(dt__gt=dt2).count(), 0)

    def test_query_filter_with_pytz_timezones(self):
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                dt = datetime.datetime(2011, 9, 1, 12, 20, 30, tzinfo=tz)
                Event.objects.create(dt=dt)
                next = dt + datetime.timedelta(seconds=3)
                prev = dt - datetime.timedelta(seconds=3)
                self.assertEqual(Event.objects.filter(dt__exact=dt).count(), 1)
                self.assertEqual(Event.objects.filter(dt__exact=next).count(), 0)
                self.assertEqual(Event.objects.filter(dt__in=(prev, next)).count(), 0)
                self.assertEqual(
                    Event.objects.filter(dt__in=(prev, dt, next)).count(), 1
                )
                self.assertEqual(
                    Event.objects.filter(dt__range=(prev, next)).count(), 1
                )

    @ignore_warnings(category=RemovedInDjango50Warning)
    def test_connection_timezone(self):
        tests = [
            (False, None, datetime.timezone),
            (False, "Africa/Nairobi", zoneinfo.ZoneInfo),
        ]
        if pytz is not None:
            tests += [
                (True, None, datetime.timezone),
                (True, "Africa/Nairobi", pytz.BaseTzInfo),
            ]
        for use_pytz, connection_tz, expected_type in tests:
            with self.subTest(use_pytz=use_pytz, connection_tz=connection_tz):
                with self.settings(USE_DEPRECATED_PYTZ=use_pytz):
                    with override_database_connection_timezone(connection_tz):
                        self.assertIsInstance(connection.timezone, expected_type)

    def test_query_convert_timezones(self):
        # Connection timezone is equal to the current timezone, datetime
        # shouldn't be converted.
        with override_database_connection_timezone("Africa/Nairobi"):
            event_datetime = datetime.datetime(2016, 1, 2, 23, 10, 11, 123, tzinfo=EAT)
            event = Event.objects.create(dt=event_datetime)
            self.assertEqual(
                Event.objects.filter(dt__date=event_datetime.date()).first(), event
            )
        # Connection timezone is not equal to the current timezone, datetime
        # should be converted (-4h).
        with override_database_connection_timezone("Asia/Bangkok"):
            event_datetime = datetime.datetime(2016, 1, 2, 3, 10, 11, tzinfo=ICT)
            event = Event.objects.create(dt=event_datetime)
            self.assertEqual(
                Event.objects.filter(dt__date=datetime.date(2016, 1, 1)).first(), event
            )

    @requires_tz_support
    def test_query_filter_with_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 12, 20, 30, tzinfo=EAT)
        Event.objects.create(dt=dt)
        dt = dt.replace(tzinfo=None)
        # naive datetimes are interpreted in local time
        with self.assertWarnsMessage(RuntimeWarning, self.naive_warning):
            self.assertEqual(Event.objects.filter(dt__exact=dt).count(), 1)
        with self.assertWarnsMessage(RuntimeWarning, self.naive_warning):
            self.assertEqual(Event.objects.filter(dt__lte=dt).count(), 1)
        with self.assertWarnsMessage(RuntimeWarning, self.naive_warning):
            self.assertEqual(Event.objects.filter(dt__gt=dt).count(), 0)

    @skipUnlessDBFeature("has_zoneinfo_database")
    def test_query_datetime_lookups(self):
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=EAT))
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 4, 30, 0, tzinfo=EAT))
        self.assertEqual(Event.objects.filter(dt__year=2011).count(), 2)
        self.assertEqual(Event.objects.filter(dt__month=1).count(), 2)
        self.assertEqual(Event.objects.filter(dt__day=1).count(), 2)
        self.assertEqual(Event.objects.filter(dt__week_day=7).count(), 2)
        self.assertEqual(Event.objects.filter(dt__iso_week_day=6).count(), 2)
        self.assertEqual(Event.objects.filter(dt__hour=1).count(), 1)
        self.assertEqual(Event.objects.filter(dt__minute=30).count(), 2)
        self.assertEqual(Event.objects.filter(dt__second=0).count(), 2)

    @skipUnlessDBFeature("has_zoneinfo_database")
    def test_query_datetime_lookups_in_other_timezone(self):
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=EAT))
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 4, 30, 0, tzinfo=EAT))
        with timezone.override(UTC):
            # These two dates fall in the same day in EAT, but in different days,
            # years and months in UTC.
            self.assertEqual(Event.objects.filter(dt__year=2011).count(), 1)
            self.assertEqual(Event.objects.filter(dt__month=1).count(), 1)
            self.assertEqual(Event.objects.filter(dt__day=1).count(), 1)
            self.assertEqual(Event.objects.filter(dt__week_day=7).count(), 1)
            self.assertEqual(Event.objects.filter(dt__iso_week_day=6).count(), 1)
            self.assertEqual(Event.objects.filter(dt__hour=22).count(), 1)
            self.assertEqual(Event.objects.filter(dt__minute=30).count(), 2)
            self.assertEqual(Event.objects.filter(dt__second=0).count(), 2)

    def test_query_aggregation(self):
        # Only min and max make sense for datetimes.
        Event.objects.create(dt=datetime.datetime(2011, 9, 1, 23, 20, 20, tzinfo=EAT))
        Event.objects.create(dt=datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT))
        Event.objects.create(dt=datetime.datetime(2011, 9, 1, 3, 20, 40, tzinfo=EAT))
        result = Event.objects.aggregate(Min("dt"), Max("dt"))
        self.assertEqual(
            result,
            {
                "dt__min": datetime.datetime(2011, 9, 1, 3, 20, 40, tzinfo=EAT),
                "dt__max": datetime.datetime(2011, 9, 1, 23, 20, 20, tzinfo=EAT),
            },
        )

    def test_query_annotation(self):
        # Only min and max make sense for datetimes.
        morning = Session.objects.create(name="morning")
        afternoon = Session.objects.create(name="afternoon")
        SessionEvent.objects.create(
            dt=datetime.datetime(2011, 9, 1, 23, 20, 20, tzinfo=EAT), session=afternoon
        )
        SessionEvent.objects.create(
            dt=datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT), session=afternoon
        )
        SessionEvent.objects.create(
            dt=datetime.datetime(2011, 9, 1, 3, 20, 40, tzinfo=EAT), session=morning
        )
        morning_min_dt = datetime.datetime(2011, 9, 1, 3, 20, 40, tzinfo=EAT)
        afternoon_min_dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        self.assertQuerysetEqual(
            Session.objects.annotate(dt=Min("events__dt")).order_by("dt"),
            [morning_min_dt, afternoon_min_dt],
            transform=lambda d: d.dt,
        )
        self.assertQuerysetEqual(
            Session.objects.annotate(dt=Min("events__dt")).filter(
                dt__lt=afternoon_min_dt
            ),
            [morning_min_dt],
            transform=lambda d: d.dt,
        )
        self.assertQuerysetEqual(
            Session.objects.annotate(dt=Min("events__dt")).filter(
                dt__gte=afternoon_min_dt
            ),
            [afternoon_min_dt],
            transform=lambda d: d.dt,
        )

    @skipUnlessDBFeature("has_zoneinfo_database")
    def test_query_datetimes(self):
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=EAT))
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 4, 30, 0, tzinfo=EAT))
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "year"),
            [datetime.datetime(2011, 1, 1, 0, 0, 0, tzinfo=EAT)],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "month"),
            [datetime.datetime(2011, 1, 1, 0, 0, 0, tzinfo=EAT)],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "day"),
            [datetime.datetime(2011, 1, 1, 0, 0, 0, tzinfo=EAT)],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "hour"),
            [
                datetime.datetime(2011, 1, 1, 1, 0, 0, tzinfo=EAT),
                datetime.datetime(2011, 1, 1, 4, 0, 0, tzinfo=EAT),
            ],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "minute"),
            [
                datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=EAT),
                datetime.datetime(2011, 1, 1, 4, 30, 0, tzinfo=EAT),
            ],
        )
        self.assertSequenceEqual(
            Event.objects.datetimes("dt", "second"),
            [
                datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=EAT),
                datetime.datetime(2011, 1, 1, 4, 30, 0, tzinfo=EAT),
            ],
        )

    @skipUnlessDBFeature("has_zoneinfo_database")
    def test_query_datetimes_in_other_timezone(self):
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=EAT))
        Event.objects.create(dt=datetime.datetime(2011, 1, 1, 4, 30, 0, tzinfo=EAT))
        with timezone.override(UTC):
            self.assertSequenceEqual(
                Event.objects.datetimes("dt", "year"),
                [
                    datetime.datetime(2010, 1, 1, 0, 0, 0, tzinfo=UTC),
                    datetime.datetime(2011, 1, 1, 0, 0, 0, tzinfo=UTC),
                ],
            )
            self.assertSequenceEqual(
                Event.objects.datetimes("dt", "month"),
                [
                    datetime.datetime(2010, 12, 1, 0, 0, 0, tzinfo=UTC),
                    datetime.datetime(2011, 1, 1, 0, 0, 0, tzinfo=UTC),
                ],
            )
            self.assertSequenceEqual(
                Event.objects.datetimes("dt", "day"),
                [
                    datetime.datetime(2010, 12, 31, 0, 0, 0, tzinfo=UTC),
                    datetime.datetime(2011, 1, 1, 0, 0, 0, tzinfo=UTC),
                ],
            )
            self.assertSequenceEqual(
                Event.objects.datetimes("dt", "hour"),
                [
                    datetime.datetime(2010, 12, 31, 22, 0, 0, tzinfo=UTC),
                    datetime.datetime(2011, 1, 1, 1, 0, 0, tzinfo=UTC),
                ],
            )
            self.assertSequenceEqual(
                Event.objects.datetimes("dt", "minute"),
                [
                    datetime.datetime(2010, 12, 31, 22, 30, 0, tzinfo=UTC),
                    datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=UTC),
                ],
            )
            self.assertSequenceEqual(
                Event.objects.datetimes("dt", "second"),
                [
                    datetime.datetime(2010, 12, 31, 22, 30, 0, tzinfo=UTC),
                    datetime.datetime(2011, 1, 1, 1, 30, 0, tzinfo=UTC),
                ],
            )

    def test_raw_sql(self):
        # Regression test for #17755
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        event = Event.objects.create(dt=dt)
        self.assertSequenceEqual(
            list(
                Event.objects.raw("SELECT * FROM timezones_event WHERE dt = %s", [dt])
            ),
            [event],
        )

    @skipUnlessDBFeature("supports_timezones")
    def test_cursor_execute_accepts_aware_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        with connection.cursor() as cursor:
            cursor.execute("INSERT INTO timezones_event (dt) VALUES (%s)", [dt])
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    @skipIfDBFeature("supports_timezones")
    def test_cursor_execute_accepts_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        utc_naive_dt = timezone.make_naive(dt, timezone.utc)
        with connection.cursor() as cursor:
            cursor.execute(
                "INSERT INTO timezones_event (dt) VALUES (%s)", [utc_naive_dt]
            )
        event = Event.objects.get()
        self.assertEqual(event.dt, dt)

    @skipUnlessDBFeature("supports_timezones")
    def test_cursor_execute_returns_aware_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        Event.objects.create(dt=dt)
        with connection.cursor() as cursor:
            cursor.execute("SELECT dt FROM timezones_event WHERE dt = %s", [dt])
            self.assertEqual(cursor.fetchall()[0][0], dt)

    @skipIfDBFeature("supports_timezones")
    def test_cursor_execute_returns_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)
        utc_naive_dt = timezone.make_naive(dt, timezone.utc)
        Event.objects.create(dt=dt)
        with connection.cursor() as cursor:
            cursor.execute(
                "SELECT dt FROM timezones_event WHERE dt = %s", [utc_naive_dt]
            )
            self.assertEqual(cursor.fetchall()[0][0], utc_naive_dt)

    @skipUnlessDBFeature("supports_timezones")
    def test_cursor_explicit_time_zone(self):
        with override_database_connection_timezone("Europe/Paris"):
            with connection.cursor() as cursor:
                cursor.execute("SELECT CURRENT_TIMESTAMP")
                now = cursor.fetchone()[0]
                self.assertEqual(str(now.tzinfo), "Europe/Paris")

    @requires_tz_support
    def test_filter_date_field_with_aware_datetime(self):
        # Regression test for #17742
        day = datetime.date(2011, 9, 1)
        AllDayEvent.objects.create(day=day)
        # This is 2011-09-02T01:30:00+03:00 in EAT
        dt = datetime.datetime(2011, 9, 1, 22, 30, 0, tzinfo=UTC)
        self.assertFalse(AllDayEvent.objects.filter(day__gte=dt).exists())

    def test_null_datetime(self):
        # Regression test for #17294
        e = MaybeEvent.objects.create()
        self.assertIsNone(e.dt)

    def test_update_with_timedelta(self):
        initial_dt = timezone.now().replace(microsecond=0)
        event = Event.objects.create(dt=initial_dt)
        Event.objects.update(dt=F("dt") + timedelta(hours=2))
        event.refresh_from_db()
        self.assertEqual(event.dt, initial_dt + timedelta(hours=2))


@override_settings(TIME_ZONE="Africa/Nairobi", USE_TZ=True)
class ForcedTimeZoneDatabaseTests(TransactionTestCase):
    """
    Test the TIME_ZONE database configuration parameter.

    Since this involves reading and writing to the same database through two
    connections, this is a TransactionTestCase.
    """

    available_apps = ["timezones"]

    @classmethod
    def setUpClass(cls):
        # @skipIfDBFeature and @skipUnlessDBFeature cannot be chained. The
        # outermost takes precedence. Handle skipping manually instead.
        if connection.features.supports_timezones:
            raise SkipTest("Database has feature(s) supports_timezones")
        if not connection.features.test_db_allows_multiple_connections:
            raise SkipTest(
                "Database doesn't support feature(s): "
                "test_db_allows_multiple_connections"
            )

        super().setUpClass()

    def test_read_datetime(self):
        fake_dt = datetime.datetime(2011, 9, 1, 17, 20, 30, tzinfo=UTC)
        Event.objects.create(dt=fake_dt)

        with override_database_connection_timezone("Asia/Bangkok"):
            event = Event.objects.get()
            dt = datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
        self.assertEqual(event.dt, dt)

    def test_write_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
        with override_database_connection_timezone("Asia/Bangkok"):
            Event.objects.create(dt=dt)

        event = Event.objects.get()
        fake_dt = datetime.datetime(2011, 9, 1, 17, 20, 30, tzinfo=UTC)
        self.assertEqual(event.dt, fake_dt)


@override_settings(TIME_ZONE="Africa/Nairobi")
class SerializationTests(SimpleTestCase):

    # Backend-specific notes:
    # - JSON supports only milliseconds, microseconds will be truncated.
    # - PyYAML dumps the UTC offset correctly for timezone-aware datetimes.
    #   When PyYAML < 5.3 loads this representation, it subtracts the offset
    #   and returns a naive datetime object in UTC. PyYAML 5.3+ loads timezones
    #   correctly.
    # Tests are adapted to take these quirks into account.

    def assert_python_contains_datetime(self, objects, dt):
        self.assertEqual(objects[0]["fields"]["dt"], dt)

    def assert_json_contains_datetime(self, json, dt):
        self.assertIn('"fields": {"dt": "%s"}' % dt, json)

    def assert_xml_contains_datetime(self, xml, dt):
        field = parseString(xml).getElementsByTagName("field")[0]
        self.assertXMLEqual(field.childNodes[0].wholeText, dt)

    def assert_yaml_contains_datetime(self, yaml, dt):
        # Depending on the yaml dumper, '!timestamp' might be absent
        self.assertRegex(yaml, r"\n  fields: {dt: !(!timestamp)? '%s'}" % re.escape(dt))

    def test_naive_datetime(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30)

        data = serializers.serialize("python", [Event(dt=dt)])
        self.assert_python_contains_datetime(data, dt)
        obj = next(serializers.deserialize("python", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("json", [Event(dt=dt)])
        self.assert_json_contains_datetime(data, "2011-09-01T13:20:30")
        obj = next(serializers.deserialize("json", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("xml", [Event(dt=dt)])
        self.assert_xml_contains_datetime(data, "2011-09-01T13:20:30")
        obj = next(serializers.deserialize("xml", data)).object
        self.assertEqual(obj.dt, dt)

        if not isinstance(
            serializers.get_serializer("yaml"), serializers.BadSerializer
        ):
            data = serializers.serialize(
                "yaml", [Event(dt=dt)], default_flow_style=None
            )
            self.assert_yaml_contains_datetime(data, "2011-09-01 13:20:30")
            obj = next(serializers.deserialize("yaml", data)).object
            self.assertEqual(obj.dt, dt)

    def test_naive_datetime_with_microsecond(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, 405060)

        data = serializers.serialize("python", [Event(dt=dt)])
        self.assert_python_contains_datetime(data, dt)
        obj = next(serializers.deserialize("python", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("json", [Event(dt=dt)])
        self.assert_json_contains_datetime(data, "2011-09-01T13:20:30.405")
        obj = next(serializers.deserialize("json", data)).object
        self.assertEqual(obj.dt, dt.replace(microsecond=405000))

        data = serializers.serialize("xml", [Event(dt=dt)])
        self.assert_xml_contains_datetime(data, "2011-09-01T13:20:30.405060")
        obj = next(serializers.deserialize("xml", data)).object
        self.assertEqual(obj.dt, dt)

        if not isinstance(
            serializers.get_serializer("yaml"), serializers.BadSerializer
        ):
            data = serializers.serialize(
                "yaml", [Event(dt=dt)], default_flow_style=None
            )
            self.assert_yaml_contains_datetime(data, "2011-09-01 13:20:30.405060")
            obj = next(serializers.deserialize("yaml", data)).object
            self.assertEqual(obj.dt, dt)

    def test_aware_datetime_with_microsecond(self):
        dt = datetime.datetime(2011, 9, 1, 17, 20, 30, 405060, tzinfo=ICT)

        data = serializers.serialize("python", [Event(dt=dt)])
        self.assert_python_contains_datetime(data, dt)
        obj = next(serializers.deserialize("python", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("json", [Event(dt=dt)])
        self.assert_json_contains_datetime(data, "2011-09-01T17:20:30.405+07:00")
        obj = next(serializers.deserialize("json", data)).object
        self.assertEqual(obj.dt, dt.replace(microsecond=405000))

        data = serializers.serialize("xml", [Event(dt=dt)])
        self.assert_xml_contains_datetime(data, "2011-09-01T17:20:30.405060+07:00")
        obj = next(serializers.deserialize("xml", data)).object
        self.assertEqual(obj.dt, dt)

        if not isinstance(
            serializers.get_serializer("yaml"), serializers.BadSerializer
        ):
            data = serializers.serialize(
                "yaml", [Event(dt=dt)], default_flow_style=None
            )
            self.assert_yaml_contains_datetime(data, "2011-09-01 17:20:30.405060+07:00")
            obj = next(serializers.deserialize("yaml", data)).object
            if HAS_YAML and yaml.__version__ < "5.3":
                self.assertEqual(obj.dt.replace(tzinfo=UTC), dt)
            else:
                self.assertEqual(obj.dt, dt)

    def test_aware_datetime_in_utc(self):
        dt = datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)

        data = serializers.serialize("python", [Event(dt=dt)])
        self.assert_python_contains_datetime(data, dt)
        obj = next(serializers.deserialize("python", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("json", [Event(dt=dt)])
        self.assert_json_contains_datetime(data, "2011-09-01T10:20:30Z")
        obj = next(serializers.deserialize("json", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("xml", [Event(dt=dt)])
        self.assert_xml_contains_datetime(data, "2011-09-01T10:20:30+00:00")
        obj = next(serializers.deserialize("xml", data)).object
        self.assertEqual(obj.dt, dt)

        if not isinstance(
            serializers.get_serializer("yaml"), serializers.BadSerializer
        ):
            data = serializers.serialize(
                "yaml", [Event(dt=dt)], default_flow_style=None
            )
            self.assert_yaml_contains_datetime(data, "2011-09-01 10:20:30+00:00")
            obj = next(serializers.deserialize("yaml", data)).object
            self.assertEqual(obj.dt.replace(tzinfo=UTC), dt)

    def test_aware_datetime_in_local_timezone(self):
        dt = datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)

        data = serializers.serialize("python", [Event(dt=dt)])
        self.assert_python_contains_datetime(data, dt)
        obj = next(serializers.deserialize("python", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("json", [Event(dt=dt)])
        self.assert_json_contains_datetime(data, "2011-09-01T13:20:30+03:00")
        obj = next(serializers.deserialize("json", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("xml", [Event(dt=dt)])
        self.assert_xml_contains_datetime(data, "2011-09-01T13:20:30+03:00")
        obj = next(serializers.deserialize("xml", data)).object
        self.assertEqual(obj.dt, dt)

        if not isinstance(
            serializers.get_serializer("yaml"), serializers.BadSerializer
        ):
            data = serializers.serialize(
                "yaml", [Event(dt=dt)], default_flow_style=None
            )
            self.assert_yaml_contains_datetime(data, "2011-09-01 13:20:30+03:00")
            obj = next(serializers.deserialize("yaml", data)).object
            if HAS_YAML and yaml.__version__ < "5.3":
                self.assertEqual(obj.dt.replace(tzinfo=UTC), dt)
            else:
                self.assertEqual(obj.dt, dt)

    def test_aware_datetime_in_other_timezone(self):
        dt = datetime.datetime(2011, 9, 1, 17, 20, 30, tzinfo=ICT)

        data = serializers.serialize("python", [Event(dt=dt)])
        self.assert_python_contains_datetime(data, dt)
        obj = next(serializers.deserialize("python", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("json", [Event(dt=dt)])
        self.assert_json_contains_datetime(data, "2011-09-01T17:20:30+07:00")
        obj = next(serializers.deserialize("json", data)).object
        self.assertEqual(obj.dt, dt)

        data = serializers.serialize("xml", [Event(dt=dt)])
        self.assert_xml_contains_datetime(data, "2011-09-01T17:20:30+07:00")
        obj = next(serializers.deserialize("xml", data)).object
        self.assertEqual(obj.dt, dt)

        if not isinstance(
            serializers.get_serializer("yaml"), serializers.BadSerializer
        ):
            data = serializers.serialize(
                "yaml", [Event(dt=dt)], default_flow_style=None
            )
            self.assert_yaml_contains_datetime(data, "2011-09-01 17:20:30+07:00")
            obj = next(serializers.deserialize("yaml", data)).object
            if HAS_YAML and yaml.__version__ < "5.3":
                self.assertEqual(obj.dt.replace(tzinfo=UTC), dt)
            else:
                self.assertEqual(obj.dt, dt)


# RemovedInDjango50Warning: When the deprecation ends, remove setUpClass() and
# USE_L10N=False. The tests should remain because format-related settings will
# take precedence over locale-dictated formats.
@override_settings(
    DATETIME_FORMAT="c", TIME_ZONE="Africa/Nairobi", USE_L10N=False, USE_TZ=True
)
class TemplateTests(SimpleTestCase):
    @classmethod
    def setUpClass(cls):
        with ignore_warnings(category=RemovedInDjango50Warning):
            super().setUpClass()

    @requires_tz_support
    def test_localtime_templatetag_and_filters(self):
        """
        Test the {% localtime %} templatetag and related filters.
        """
        datetimes = {
            "utc": datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC),
            "eat": datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT),
            "ict": datetime.datetime(2011, 9, 1, 17, 20, 30, tzinfo=ICT),
            "naive": datetime.datetime(2011, 9, 1, 13, 20, 30),
        }
        templates = {
            "notag": Template(
                "{% load tz %}"
                "{{ dt }}|{{ dt|localtime }}|{{ dt|utc }}|{{ dt|timezone:ICT }}"
            ),
            "noarg": Template(
                "{% load tz %}{% localtime %}{{ dt }}|{{ dt|localtime }}|"
                "{{ dt|utc }}|{{ dt|timezone:ICT }}{% endlocaltime %}"
            ),
            "on": Template(
                "{% load tz %}{% localtime on %}{{ dt }}|{{ dt|localtime }}|"
                "{{ dt|utc }}|{{ dt|timezone:ICT }}{% endlocaltime %}"
            ),
            "off": Template(
                "{% load tz %}{% localtime off %}{{ dt }}|{{ dt|localtime }}|"
                "{{ dt|utc }}|{{ dt|timezone:ICT }}{% endlocaltime %}"
            ),
        }

        # Transform a list of keys in 'datetimes' to the expected template
        # output. This makes the definition of 'results' more readable.
        def t(*result):
            return "|".join(datetimes[key].isoformat() for key in result)

        # Results for USE_TZ = True

        results = {
            "utc": {
                "notag": t("eat", "eat", "utc", "ict"),
                "noarg": t("eat", "eat", "utc", "ict"),
                "on": t("eat", "eat", "utc", "ict"),
                "off": t("utc", "eat", "utc", "ict"),
            },
            "eat": {
                "notag": t("eat", "eat", "utc", "ict"),
                "noarg": t("eat", "eat", "utc", "ict"),
                "on": t("eat", "eat", "utc", "ict"),
                "off": t("eat", "eat", "utc", "ict"),
            },
            "ict": {
                "notag": t("eat", "eat", "utc", "ict"),
                "noarg": t("eat", "eat", "utc", "ict"),
                "on": t("eat", "eat", "utc", "ict"),
                "off": t("ict", "eat", "utc", "ict"),
            },
            "naive": {
                "notag": t("naive", "eat", "utc", "ict"),
                "noarg": t("naive", "eat", "utc", "ict"),
                "on": t("naive", "eat", "utc", "ict"),
                "off": t("naive", "eat", "utc", "ict"),
            },
        }

        for k1, dt in datetimes.items():
            for k2, tpl in templates.items():
                ctx = Context({"dt": dt, "ICT": ICT})
                actual = tpl.render(ctx)
                expected = results[k1][k2]
                self.assertEqual(
                    actual, expected, "%s / %s: %r != %r" % (k1, k2, actual, expected)
                )

        # Changes for USE_TZ = False

        results["utc"]["notag"] = t("utc", "eat", "utc", "ict")
        results["ict"]["notag"] = t("ict", "eat", "utc", "ict")

        with self.settings(USE_TZ=False):
            for k1, dt in datetimes.items():
                for k2, tpl in templates.items():
                    ctx = Context({"dt": dt, "ICT": ICT})
                    actual = tpl.render(ctx)
                    expected = results[k1][k2]
                    self.assertEqual(
                        actual,
                        expected,
                        "%s / %s: %r != %r" % (k1, k2, actual, expected),
                    )

    def test_localtime_filters_with_iana(self):
        """
        Test the |localtime, |utc, and |timezone filters with iana zones.
        """
        # Use an IANA timezone as local time
        tpl = Template("{% load tz %}{{ dt|localtime }}|{{ dt|utc }}")
        ctx = Context({"dt": datetime.datetime(2011, 9, 1, 12, 20, 30)})

        with self.settings(TIME_ZONE="Europe/Paris"):
            self.assertEqual(
                tpl.render(ctx), "2011-09-01T12:20:30+02:00|2011-09-01T10:20:30+00:00"
            )

        # Use an IANA timezone as argument
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                tpl = Template("{% load tz %}{{ dt|timezone:tz }}")
                ctx = Context(
                    {
                        "dt": datetime.datetime(2011, 9, 1, 13, 20, 30),
                        "tz": tz,
                    }
                )
                self.assertEqual(tpl.render(ctx), "2011-09-01T12:20:30+02:00")

    def test_localtime_templatetag_invalid_argument(self):
        with self.assertRaises(TemplateSyntaxError):
            Template("{% load tz %}{% localtime foo %}{% endlocaltime %}").render()

    def test_localtime_filters_do_not_raise_exceptions(self):
        """
        Test the |localtime, |utc, and |timezone filters on bad inputs.
        """
        tpl = Template(
            "{% load tz %}{{ dt }}|{{ dt|localtime }}|{{ dt|utc }}|{{ dt|timezone:tz }}"
        )
        with self.settings(USE_TZ=True):
            # bad datetime value
            ctx = Context({"dt": None, "tz": ICT})
            self.assertEqual(tpl.render(ctx), "None|||")
            ctx = Context({"dt": "not a date", "tz": ICT})
            self.assertEqual(tpl.render(ctx), "not a date|||")
            # bad timezone value
            tpl = Template("{% load tz %}{{ dt|timezone:tz }}")
            ctx = Context({"dt": datetime.datetime(2011, 9, 1, 13, 20, 30), "tz": None})
            self.assertEqual(tpl.render(ctx), "")
            ctx = Context(
                {"dt": datetime.datetime(2011, 9, 1, 13, 20, 30), "tz": "not a tz"}
            )
            self.assertEqual(tpl.render(ctx), "")

    @requires_tz_support
    def test_timezone_templatetag(self):
        """
        Test the {% timezone %} templatetag.
        """
        tpl = Template(
            "{% load tz %}"
            "{{ dt }}|"
            "{% timezone tz1 %}"
            "{{ dt }}|"
            "{% timezone tz2 %}"
            "{{ dt }}"
            "{% endtimezone %}"
            "{% endtimezone %}"
        )
        ctx = Context(
            {
                "dt": datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC),
                "tz1": ICT,
                "tz2": None,
            }
        )
        self.assertEqual(
            tpl.render(ctx),
            "2011-09-01T13:20:30+03:00|2011-09-01T17:20:30+07:00|"
            "2011-09-01T13:20:30+03:00",
        )

    def test_timezone_templatetag_with_iana(self):
        """
        Test the {% timezone %} templatetag with IANA time zone providers.
        """
        tpl = Template("{% load tz %}{% timezone tz %}{{ dt }}{% endtimezone %}")

        # Use a IANA timezone as argument
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                ctx = Context(
                    {
                        "dt": datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT),
                        "tz": tz,
                    }
                )
                self.assertEqual(tpl.render(ctx), "2011-09-01T12:20:30+02:00")

        # Use a IANA timezone name as argument
        ctx = Context(
            {
                "dt": datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT),
                "tz": "Europe/Paris",
            }
        )
        self.assertEqual(tpl.render(ctx), "2011-09-01T12:20:30+02:00")

    @ignore_warnings(category=RemovedInDjango50Warning)
    def test_timezone_templatetag_invalid_argument(self):
        with self.assertRaises(TemplateSyntaxError):
            Template("{% load tz %}{% timezone %}{% endtimezone %}").render()
        with self.assertRaises(zoneinfo.ZoneInfoNotFoundError):
            Template("{% load tz %}{% timezone tz %}{% endtimezone %}").render(
                Context({"tz": "foobar"})
            )
        if pytz is not None:
            with override_settings(USE_DEPRECATED_PYTZ=True), self.assertRaises(
                pytz.UnknownTimeZoneError
            ):
                Template("{% load tz %}{% timezone tz %}{% endtimezone %}").render(
                    Context({"tz": "foobar"})
                )

    @skipIf(sys.platform == "win32", "Windows uses non-standard time zone names")
    def test_get_current_timezone_templatetag(self):
        """
        Test the {% get_current_timezone %} templatetag.
        """
        tpl = Template(
            "{% load tz %}{% get_current_timezone as time_zone %}{{ time_zone }}"
        )

        self.assertEqual(tpl.render(Context()), "Africa/Nairobi")
        with timezone.override(UTC):
            self.assertEqual(tpl.render(Context()), "UTC")

        tpl = Template(
            "{% load tz %}{% timezone tz %}{% get_current_timezone as time_zone %}"
            "{% endtimezone %}{{ time_zone }}"
        )

        self.assertEqual(tpl.render(Context({"tz": ICT})), "+0700")
        with timezone.override(UTC):
            self.assertEqual(tpl.render(Context({"tz": ICT})), "+0700")

    def test_get_current_timezone_templatetag_with_iana(self):
        """
        Test the {% get_current_timezone %} templatetag with pytz.
        """
        tpl = Template(
            "{% load tz %}{% get_current_timezone as time_zone %}{{ time_zone }}"
        )
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                with timezone.override(tz):
                    self.assertEqual(tpl.render(Context()), "Europe/Paris")

        tpl = Template(
            "{% load tz %}{% timezone 'Europe/Paris' %}"
            "{% get_current_timezone as time_zone %}{% endtimezone %}"
            "{{ time_zone }}"
        )
        self.assertEqual(tpl.render(Context()), "Europe/Paris")

    def test_get_current_timezone_templatetag_invalid_argument(self):
        msg = (
            "'get_current_timezone' requires 'as variable' (got "
            "['get_current_timezone'])"
        )
        with self.assertRaisesMessage(TemplateSyntaxError, msg):
            Template("{% load tz %}{% get_current_timezone %}").render()

    @skipIf(sys.platform == "win32", "Windows uses non-standard time zone names")
    def test_tz_template_context_processor(self):
        """
        Test the django.template.context_processors.tz template context processor.
        """
        tpl = Template("{{ TIME_ZONE }}")
        context = Context()
        self.assertEqual(tpl.render(context), "")
        request_context = RequestContext(
            HttpRequest(), processors=[context_processors.tz]
        )
        self.assertEqual(tpl.render(request_context), "Africa/Nairobi")

    @requires_tz_support
    def test_date_and_time_template_filters(self):
        tpl = Template("{{ dt|date:'Y-m-d' }} at {{ dt|time:'H:i:s' }}")
        ctx = Context({"dt": datetime.datetime(2011, 9, 1, 20, 20, 20, tzinfo=UTC)})
        self.assertEqual(tpl.render(ctx), "2011-09-01 at 23:20:20")
        with timezone.override(ICT):
            self.assertEqual(tpl.render(ctx), "2011-09-02 at 03:20:20")

    def test_date_and_time_template_filters_honor_localtime(self):
        tpl = Template(
            "{% load tz %}{% localtime off %}{{ dt|date:'Y-m-d' }} at "
            "{{ dt|time:'H:i:s' }}{% endlocaltime %}"
        )
        ctx = Context({"dt": datetime.datetime(2011, 9, 1, 20, 20, 20, tzinfo=UTC)})
        self.assertEqual(tpl.render(ctx), "2011-09-01 at 20:20:20")
        with timezone.override(ICT):
            self.assertEqual(tpl.render(ctx), "2011-09-01 at 20:20:20")

    @requires_tz_support
    def test_now_template_tag_uses_current_time_zone(self):
        # Regression for #17343
        tpl = Template('{% now "O" %}')
        self.assertEqual(tpl.render(Context({})), "+0300")
        with timezone.override(ICT):
            self.assertEqual(tpl.render(Context({})), "+0700")


# RemovedInDjango50Warning: When the deprecation ends, remove setUpClass() and
# USE_L10N=False. The tests should remain because format-related settings will
# take precedence over locale-dictated formats.
@override_settings(
    DATETIME_FORMAT="c", TIME_ZONE="Africa/Nairobi", USE_L10N=False, USE_TZ=False
)
class LegacyFormsTests(TestCase):
    @classmethod
    def setUpClass(cls):
        with ignore_warnings(category=RemovedInDjango50Warning):
            super().setUpClass()

    def test_form(self):
        form = EventForm({"dt": "2011-09-01 13:20:30"})
        self.assertTrue(form.is_valid())
        self.assertEqual(
            form.cleaned_data["dt"], datetime.datetime(2011, 9, 1, 13, 20, 30)
        )

    def test_form_with_non_existent_time(self):
        form = EventForm({"dt": "2011-03-27 02:30:00"})
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                with timezone.override(tz):
                    # This is a bug.
                    self.assertTrue(form.is_valid())
                    self.assertEqual(
                        form.cleaned_data["dt"],
                        datetime.datetime(2011, 3, 27, 2, 30, 0),
                    )

    def test_form_with_ambiguous_time(self):
        form = EventForm({"dt": "2011-10-30 02:30:00"})
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                with timezone.override(tz):
                    # This is a bug.
                    self.assertTrue(form.is_valid())
                    self.assertEqual(
                        form.cleaned_data["dt"],
                        datetime.datetime(2011, 10, 30, 2, 30, 0),
                    )

    def test_split_form(self):
        form = EventSplitForm({"dt_0": "2011-09-01", "dt_1": "13:20:30"})
        self.assertTrue(form.is_valid())
        self.assertEqual(
            form.cleaned_data["dt"], datetime.datetime(2011, 9, 1, 13, 20, 30)
        )

    def test_model_form(self):
        EventModelForm({"dt": "2011-09-01 13:20:30"}).save()
        e = Event.objects.get()
        self.assertEqual(e.dt, datetime.datetime(2011, 9, 1, 13, 20, 30))


# RemovedInDjango50Warning: When the deprecation ends, remove setUpClass() and
# USE_L10N=False. The tests should remain because format-related settings will
# take precedence over locale-dictated formats.
@override_settings(
    DATETIME_FORMAT="c", TIME_ZONE="Africa/Nairobi", USE_L10N=False, USE_TZ=True
)
class NewFormsTests(TestCase):
    @classmethod
    def setUpClass(cls):
        with ignore_warnings(category=RemovedInDjango50Warning):
            super().setUpClass()

    @requires_tz_support
    def test_form(self):
        form = EventForm({"dt": "2011-09-01 13:20:30"})
        self.assertTrue(form.is_valid())
        self.assertEqual(
            form.cleaned_data["dt"],
            datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC),
        )

    def test_form_with_other_timezone(self):
        form = EventForm({"dt": "2011-09-01 17:20:30"})
        with timezone.override(ICT):
            self.assertTrue(form.is_valid())
            self.assertEqual(
                form.cleaned_data["dt"],
                datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC),
            )

    def test_form_with_non_existent_time(self):
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                with timezone.override(tz):
                    form = EventForm({"dt": "2011-03-27 02:30:00"})
                    self.assertFalse(form.is_valid())
                    self.assertEqual(
                        form.errors["dt"],
                        [
                            "2011-03-27 02:30:00 couldn’t be interpreted in time zone "
                            "Europe/Paris; it may be ambiguous or it may not exist."
                        ],
                    )

    def test_form_with_ambiguous_time(self):
        for tz in get_timezones("Europe/Paris"):
            with self.subTest(repr(tz)):
                with timezone.override(tz):
                    form = EventForm({"dt": "2011-10-30 02:30:00"})
                    self.assertFalse(form.is_valid())
                    self.assertEqual(
                        form.errors["dt"],
                        [
                            "2011-10-30 02:30:00 couldn’t be interpreted in time zone "
                            "Europe/Paris; it may be ambiguous or it may not exist."
                        ],
                    )

    @requires_tz_support
    def test_split_form(self):
        form = EventSplitForm({"dt_0": "2011-09-01", "dt_1": "13:20:30"})
        self.assertTrue(form.is_valid())
        self.assertEqual(
            form.cleaned_data["dt"],
            datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC),
        )

    @requires_tz_support
    def test_localized_form(self):
        form = EventLocalizedForm(
            initial={"dt": datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)}
        )
        with timezone.override(ICT):
            self.assertIn("2011-09-01 17:20:30", str(form))

    @requires_tz_support
    def test_model_form(self):
        EventModelForm({"dt": "2011-09-01 13:20:30"}).save()
        e = Event.objects.get()
        self.assertEqual(e.dt, datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC))

    @requires_tz_support
    def test_localized_model_form(self):
        form = EventLocalizedModelForm(
            instance=Event(dt=datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT))
        )
        with timezone.override(ICT):
            self.assertIn("2011-09-01 17:20:30", str(form))


@override_settings(
    DATETIME_FORMAT="c",
    TIME_ZONE="Africa/Nairobi",
    USE_L10N=False,
    USE_TZ=True,
    ROOT_URLCONF="timezones.urls",
)
class AdminTests(TestCase):
    @classmethod
    def setUpClass(cls):
        with ignore_warnings(category=RemovedInDjango50Warning):
            super().setUpClass()

    @classmethod
    def setUpTestData(cls):
        cls.u1 = User.objects.create_user(
            password="secret",
            last_login=datetime.datetime(2007, 5, 30, 13, 20, 10, tzinfo=UTC),
            is_superuser=True,
            username="super",
            first_name="Super",
            last_name="User",
            email="super@example.com",
            is_staff=True,
            is_active=True,
            date_joined=datetime.datetime(2007, 5, 30, 13, 20, 10, tzinfo=UTC),
        )

    def setUp(self):
        self.client.force_login(self.u1)

    @requires_tz_support
    def test_changelist(self):
        e = Event.objects.create(
            dt=datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
        )
        response = self.client.get(reverse("admin_tz:timezones_event_changelist"))
        self.assertContains(response, e.dt.astimezone(EAT).isoformat())

    def test_changelist_in_other_timezone(self):
        e = Event.objects.create(
            dt=datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
        )
        with timezone.override(ICT):
            response = self.client.get(reverse("admin_tz:timezones_event_changelist"))
        self.assertContains(response, e.dt.astimezone(ICT).isoformat())

    @requires_tz_support
    def test_change_editable(self):
        e = Event.objects.create(
            dt=datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
        )
        response = self.client.get(
            reverse("admin_tz:timezones_event_change", args=(e.pk,))
        )
        self.assertContains(response, e.dt.astimezone(EAT).date().isoformat())
        self.assertContains(response, e.dt.astimezone(EAT).time().isoformat())

    def test_change_editable_in_other_timezone(self):
        e = Event.objects.create(
            dt=datetime.datetime(2011, 9, 1, 10, 20, 30, tzinfo=UTC)
        )
        with timezone.override(ICT):
            response = self.client.get(
                reverse("admin_tz:timezones_event_change", args=(e.pk,))
            )
        self.assertContains(response, e.dt.astimezone(ICT).date().isoformat())
        self.assertContains(response, e.dt.astimezone(ICT).time().isoformat())

    @requires_tz_support
    def test_change_readonly(self):
        Timestamp.objects.create()
        # re-fetch the object for backends that lose microseconds (MySQL)
        t = Timestamp.objects.get()
        response = self.client.get(
            reverse("admin_tz:timezones_timestamp_change", args=(t.pk,))
        )
        self.assertContains(response, t.created.astimezone(EAT).isoformat())

    def test_change_readonly_in_other_timezone(self):
        Timestamp.objects.create()
        # re-fetch the object for backends that lose microseconds (MySQL)
        t = Timestamp.objects.get()
        with timezone.override(ICT):
            response = self.client.get(
                reverse("admin_tz:timezones_timestamp_change", args=(t.pk,))
            )
        self.assertContains(response, t.created.astimezone(ICT).isoformat())