[Python-checkins] python/dist/src/Lib/test test_datetime.py,1.13,1.14

tim_one@users.sourceforge.net tim_one@users.sourceforge.net
Mon, 30 Dec 2002 09:09:42 -0800


Update of /cvsroot/python/python/dist/src/Lib/test
In directory sc8-pr-cvs1:/tmp/cvs-serv15629/python/Lib/test

Modified Files:
	test_datetime.py 
Log Message:
Beefed up the timezone conversion test by adding a phony UTC zone that's
west of the US zones getting converted, and also by using Eastern "as if"
it were UTC (wrt Pacific), and vice versa.


Index: test_datetime.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/test/test_datetime.py,v
retrieving revision 1.13
retrieving revision 1.14
diff -C2 -d -r1.13 -r1.14
*** test_datetime.py	29 Dec 2002 23:44:49 -0000	1.13
--- test_datetime.py	30 Dec 2002 17:09:40 -0000	1.14
***************
*** 2572,2576 ****
  Eastern = USTimeZone(-5, "Eastern", "EST", "EDT")
  Pacific = USTimeZone(-8, "Pacific", "PST", "PDT")
! UTC = FixedOffset(0, "UTC", 0)
  
  class TestTimezoneConversions(unittest.TestCase):
--- 2572,2579 ----
  Eastern = USTimeZone(-5, "Eastern", "EST", "EDT")
  Pacific = USTimeZone(-8, "Pacific", "PST", "PDT")
! utc_real = FixedOffset(0, "UTC", 0)
! # For better test coverage, we want another flavor of UTC that's west of
! # the Eastern and Pacific timezones.
! utc_fake = FixedOffset(-12, "UTCfake", 0)
  
  class TestTimezoneConversions(unittest.TestCase):
***************
*** 2579,2650 ****
      dstoff = datetimetz(2002, 10, 27, 2)
  
!     def test_easy(self):
!         # Despite the name of this test, the endcases are excruciating.
!         for tz in Eastern, Pacific:
!             dston = self.dston.replace(tzinfo=tz)
!             dstoff = self.dstoff.replace(tzinfo=tz)
!             for delta in (timedelta(weeks=13),
!                           DAY,
!                           HOUR,
!                           timedelta(minutes=1),
!                           timedelta(microseconds=1)):
!                 for during in dston, dston + delta, dstoff - delta:
!                     self.assertEqual(during.dst(), HOUR)
!                     asutc = during.astimezone(UTC)
!                     there_and_back = asutc.astimezone(tz)
  
!                     # Conversion to UTC and back isn't always an identity here,
!                     # because there are redundant spellings (in local time) of
!                     # UTC time when DST begins:  the clock jumps from 1:59:59
!                     # to 3:00:00, and a local time of 2:MM:SS doesn't really
!                     # make sense then.  The classes above treat 2:MM:SS as
!                     # daylight time then (it's "after 2am"), really an alias
!                     # for 1:MM:SS standard time.  The latter form is what
!                     # conversion back from UTC produces.
!                     if during.date() == dston.date() and during.hour == 2:
!                         # We're in the redundant hour, and coming back from
!                         # UTC gives the 1:MM:SS standard-time spelling.
!                         self.assertEqual(there_and_back + HOUR, during)
!                         # Although during was considered to be in daylight
!                         # time, there_and_back is not.
!                         self.assertEqual(there_and_back.dst(), ZERO)
!                         # They're the same times in UTC.
!                         self.assertEqual(there_and_back.astimezone(UTC),
!                                          during.astimezone(UTC))
!                     else:
!                         # We're not in the redundant hour.
!                         self.assertEqual(during, there_and_back)
  
!                     # Because we have a redundant spelling when DST begins,
!                     # there is (unforunately) an hour when DST ends that can't
!                     # be spelled at all in local time.  When DST ends, the
!                     # clock jumps from 1:59:59 back to 1:00:00 again.  The
!                     # hour beginning then has no spelling in local time:
!                     # 1:MM:SS is taken to be daylight time, and 2:MM:SS as
!                     # standard time.  The hour 1:MM:SS standard time ==
!                     # 2:MM:SS daylight time can't be expressed in local time.
!                     nexthour_utc = asutc + HOUR
!                     nexthour_tz = nexthour_utc.astimezone(tz)
!                     if during.date() == dstoff.date() and during.hour == 1:
!                         # We're in the hour before DST ends.  The hour after
!                         # is ineffable.
!                         # For concreteness, picture Eastern.  during is of
!                         # the form 1:MM:SS, it's daylight time, so that's
!                         # 5:MM:SS UTC.  Adding an hour gives 6:MM:SS UTC.
!                         # Daylight time ended at 2+4 == 6:00:00 UTC, so
!                         # 6:MM:SS is (correctly) taken to be standard time.
!                         # But standard time is at offset -5, and that maps
!                         # right back to the 1:MM:SS Eastern we started with.
!                         # That's correct, too, *if* 1:MM:SS were taken as
!                         # being standard time.  But it's not -- on this day
!                         # it's taken as daylight time.
!                         self.assertEqual(during, nexthour_tz)
!                     else:
!                         self.assertEqual(nexthour_tz - during, HOUR)
  
!                 for outside in dston - delta, dstoff, dstoff + delta:
!                     self.assertEqual(outside.dst(), ZERO)
!                     there_and_back = outside.astimezone(UTC).astimezone(tz)
!                     self.assertEqual(outside, there_and_back)
  
  
--- 2582,2664 ----
      dstoff = datetimetz(2002, 10, 27, 2)
  
!     def convert_between_tz_and_utc(self, tz, utc):
!         dston = self.dston.replace(tzinfo=tz)
!         dstoff = self.dstoff.replace(tzinfo=tz)
!         for delta in (timedelta(weeks=13),
!                       DAY,
!                       HOUR,
!                       timedelta(minutes=1),
!                       timedelta(microseconds=1)):
  
!             for during in dston, dston + delta, dstoff - delta:
!                 self.assertEqual(during.dst(), HOUR)
!                 asutc = during.astimezone(utc)
!                 there_and_back = asutc.astimezone(tz)
  
!                 # Conversion to UTC and back isn't always an identity here,
!                 # because there are redundant spellings (in local time) of
!                 # UTC time when DST begins:  the clock jumps from 1:59:59
!                 # to 3:00:00, and a local time of 2:MM:SS doesn't really
!                 # make sense then.  The classes above treat 2:MM:SS as
!                 # daylight time then (it's "after 2am"), really an alias
!                 # for 1:MM:SS standard time.  The latter form is what
!                 # conversion back from UTC produces.
!                 if during.date() == dston.date() and during.hour == 2:
!                     # We're in the redundant hour, and coming back from
!                     # UTC gives the 1:MM:SS standard-time spelling.
!                     self.assertEqual(there_and_back + HOUR, during)
!                     # Although during was considered to be in daylight
!                     # time, there_and_back is not.
!                     self.assertEqual(there_and_back.dst(), ZERO)
!                     # They're the same times in UTC.
!                     self.assertEqual(there_and_back.astimezone(utc),
!                                      during.astimezone(utc))
!                 else:
!                     # We're not in the redundant hour.
!                     self.assertEqual(during, there_and_back)
  
!                 # Because we have a redundant spelling when DST begins,
!                 # there is (unforunately) an hour when DST ends that can't
!                 # be spelled at all in local time.  When DST ends, the
!                 # clock jumps from 1:59:59 back to 1:00:00 again.  The
!                 # hour beginning then has no spelling in local time:
!                 # 1:MM:SS is taken to be daylight time, and 2:MM:SS as
!                 # standard time.  The hour 1:MM:SS standard time ==
!                 # 2:MM:SS daylight time can't be expressed in local time.
!                 nexthour_utc = asutc + HOUR
!                 nexthour_tz = nexthour_utc.astimezone(tz)
!                 if during.date() == dstoff.date() and during.hour == 1:
!                     # We're in the hour before DST ends.  The hour after
!                     # is ineffable.
!                     # For concreteness, picture Eastern.  during is of
!                     # the form 1:MM:SS, it's daylight time, so that's
!                     # 5:MM:SS UTC.  Adding an hour gives 6:MM:SS UTC.
!                     # Daylight time ended at 2+4 == 6:00:00 UTC, so
!                     # 6:MM:SS is (correctly) taken to be standard time.
!                     # But standard time is at offset -5, and that maps
!                     # right back to the 1:MM:SS Eastern we started with.
!                     # That's correct, too, *if* 1:MM:SS were taken as
!                     # being standard time.  But it's not -- on this day
!                     # it's taken as daylight time.
!                     self.assertEqual(during, nexthour_tz)
!                 else:
!                     self.assertEqual(nexthour_tz - during, HOUR)
! 
!             for outside in dston - delta, dstoff, dstoff + delta:
!                 self.assertEqual(outside.dst(), ZERO)
!                 there_and_back = outside.astimezone(utc).astimezone(tz)
!                 self.assertEqual(outside, there_and_back)
! 
!     def test_easy(self):
!         # Despite the name of this test, the endcases are excruciating.
!         self.convert_between_tz_and_utc(Eastern, utc_real)
!         self.convert_between_tz_and_utc(Pacific, utc_real)
!         self.convert_between_tz_and_utc(Eastern, utc_fake)
!         self.convert_between_tz_and_utc(Pacific, utc_fake)
!         # The next is really dancing near the edge.  It works because
!         # Pacific and Eastern are far enough apart that their "problem
!         # hours" don't overlap.
!         self.convert_between_tz_and_utc(Eastern, Pacific)
!         self.convert_between_tz_and_utc(Pacific, Eastern)