Fixed #25181 -- Added localdate() function to get date in a different time zone.

Thanks Konrad Świat for the original patch.

4 files changed, 65 insertions, 5 deletions

diff --git a/django/utils/timezone.py b/django/utils/timezone.py
index 20d59f5fed..e2c6967607 100644
--- a/django/utils/timezone.py
+++ b/django/utils/timezone.py
@@ -299,13 +299,18 @@ def template_localtime(value, use_tz=None):
 
 # Utilities
 
-def localtime(value, timezone=None):
+def localtime(value=None, timezone=None):
     """
     Converts an aware datetime.datetime to local time.
 
+    Only aware datetimes are allowed. When value is omitted, it defaults to
+    now().
+
     Local time is defined by the current time zone, unless another time zone
     is specified.
     """
+    if value is None:
+        value = now()
     if timezone is None:
         timezone = get_current_timezone()
     # If `value` is naive, astimezone() will raise a ValueError,
@@ -317,6 +322,19 @@ def localtime(value, timezone=None):
     return value
 
 
+def localdate(value=None, timezone=None):
+    """
+    Convert an aware datetime to local time and return the value's date.
+
+    Only aware datetimes are allowed. When value is omitted, it defaults to
+    now().
+
+    Local time is defined by the current time zone, unless another time zone is
+    specified.
+    """
+    return localtime(value, timezone).date()
+
+
 def now():
     """
     Returns an aware or naive datetime.datetime, depending on settings.USE_TZ.
diff --git a/django/views/generic/dates.py b/django/views/generic/dates.py
index 52b3b39062..938c538535 100644
--- a/django/views/generic/dates.py
+++ b/django/views/generic/dates.py
@@ -792,6 +792,6 @@ def timezone_today():
     Return the current date in the current time zone.
     """
     if settings.USE_TZ:
-        return timezone.localtime(timezone.now()).date()
+        return timezone.localdate()
     else:
         return datetime.date.today()
diff --git a/docs/ref/utils.txt b/docs/ref/utils.txt
index 893ecb5792..00ac7970d7 100644
--- a/docs/ref/utils.txt
+++ b/docs/ref/utils.txt
@@ -974,14 +974,32 @@ appropriate entities.
 
     ``override`` is also usable as a function decorator.
 
-.. function:: localtime(value, timezone=None)
+.. function:: localtime(value=None, timezone=None)
 
     Converts an aware :class:`~datetime.datetime` to a different time zone,
     by default the :ref:`current time zone <default-current-time-zone>`.
 
+    When ``value`` is omitted, it defaults to :func:`now`.
+
     This function doesn't work on naive datetimes; use :func:`make_aware`
     instead.
 
+    .. versionchanged:: 1.11
+
+        In older versions, ``value`` is a required argument.
+
+.. function:: localdate(value=None, timezone=None)
+
+    .. versionadded:: 1.11
+
+    Uses :func:`localtime` to convert an aware :class:`~datetime.datetime` to a
+    :meth:`~datetime.datetime.date` in a different time zone, by default the
+    :ref:`current time zone <default-current-time-zone>`.
+
+    When ``value`` is omitted, it defaults to :func:`now`.
+
+    This function doesn't work on naive datetimes.
+
 .. function:: now()
 
     Returns a :class:`~datetime.datetime` that represents the
diff --git a/tests/utils_tests/test_timezone.py b/tests/utils_tests/test_timezone.py
index 5f21c06bae..9dc7941b4b 100644
--- a/tests/utils_tests/test_timezone.py
+++ b/tests/utils_tests/test_timezone.py
@@ -4,7 +4,7 @@ import pickle
 import sys
 import unittest
 
-from django.test import SimpleTestCase, override_settings
+from django.test import SimpleTestCase, mock, override_settings
 from django.utils import timezone
 
 try:
@@ -27,7 +27,10 @@ class TimezoneTests(SimpleTestCase):
     def test_localtime(self):
         now = datetime.datetime.utcnow().replace(tzinfo=timezone.utc)
         local_tz = timezone.LocalTimezone()
-        local_now = timezone.localtime(now, local_tz)
+        with timezone.override(local_tz):
+            local_now = timezone.localtime(now)
+            self.assertEqual(local_now.tzinfo, local_tz)
+        local_now = timezone.localtime(now, timezone=local_tz)
         self.assertEqual(local_now.tzinfo, local_tz)
 
     def test_localtime_naive(self):
@@ -54,6 +57,27 @@ class TimezoneTests(SimpleTestCase):
         with override_settings(USE_TZ=False):
             self.assertTrue(timezone.is_naive(timezone.now()))
 
+    def test_localdate(self):
+        naive = datetime.datetime(2015, 1, 1, 0, 0, 1)
+        if PY36:
+            self.assertEqual(timezone.localdate(naive), datetime.date(2015, 1, 1))
+            self.assertEqual(timezone.localdate(naive, timezone=EAT), datetime.date(2015, 1, 1))
+        else:
+            with self.assertRaisesMessage(ValueError, 'astimezone() cannot be applied to a naive datetime'):
+                timezone.localdate(naive)
+            with self.assertRaisesMessage(ValueError, 'astimezone() cannot be applied to a naive datetime'):
+                timezone.localdate(naive, timezone=EAT)
+
+        aware = datetime.datetime(2015, 1, 1, 0, 0, 1, tzinfo=ICT)
+        self.assertEqual(timezone.localdate(aware, timezone=EAT), datetime.date(2014, 12, 31))
+        with timezone.override(EAT):
+            self.assertEqual(timezone.localdate(aware), datetime.date(2014, 12, 31))
+
+        with mock.patch('django.utils.timezone.now', return_value=aware):
+            self.assertEqual(timezone.localdate(timezone=EAT), datetime.date(2014, 12, 31))
+            with timezone.override(EAT):
+                self.assertEqual(timezone.localdate(), datetime.date(2014, 12, 31))
+
     def test_override(self):
         default = timezone.get_default_timezone()
         try: