OOPS setting US/Pacific-New timezone

pytz should sanitize common_timezones and all_timezones so that only timezones that are actually available are listed. It isn't a problem with the default setup, but is an issue when the timezone files being used are not the ones distributed with pytz (such as is the case with the Ubuntu package).

This is another manifestation of Bug #207604.

The following monkey patch should get Launchpad happy for now with minimal effort:

$ python
Python 2.5.2 (r252:60911, May 7 2008, 15:21:12)
[GCC 4.2.3 (Ubuntu 4.2.3-2ubuntu7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import pytz
>>> 'US/Pacific-New' in pytz.common_timezones
True
>>> for timezone_name in pytz.all_timezones[:]:
... try:
... ignored_tzinfo = pytz.timezone(timezone_name)
... except:
... pytz.all_timezones.remove(timezone_name)
... pytz.common_timezones.remove(timezone_name)
...
>>> 'US/Pacific-New' in pytz.common_timezones

Loading all the timezone objects is definitely the most thorough check, but it takes at least 300 milliseconds. Checking that the timezone files exist with os.path.isfile only takes 4 milliseconds.

>>> for timezone_name in pytz.common_timezones:
... if not os.path.isfile(os.path.join(dir, timezone_name)):
... pytz.common_timezones.remove(timezone_name)

pytz.timezone() should also catch the IOError and throw a pytz.UnknownTimeZoneError even though it is very unlikely to occur if pytz.all_timezones_set is clean, but that also depends on whether they are preloaded or if all_timezones_set is just verified with os.path.isfile().

Fixed and cherry picked.

This was fixed by running a DB query <https://pastebin.canonical.com/6996/> which converted US/Pacific-New timezone to US/Pacific

More details <https://launchpad.canonical.com/LaunchpadProductionStatus?action=recall&rev=958>

This bug was fixed in the package python-tz - 2008h-1

---------------
python-tz (2008h-1) unstable; urgency=low

  * New upstream version.
    - Fixes lookup errors with unknown timezones (error setting US/Pacific-New
      timezone. LP: #244681).
  * debian/copyright: Update copyright year and download location.
  * debian/control: Update homepage.

python-tz (2008c-2) unstable; urgency=low

  * Do not use setuptools to build the package (the setup falls back to
    distutils).
  * Set version to 2008c. Closes: #489979.

python-tz (2008c-1) unstable; urgency=low

  * New upstream release.

 -- Matthias Klose <email address hidden> Thu, 13 Nov 2008 14:50:15 +0000

I ran setup for pytz 2009l on my windows box. My zoneinfo directory has files for all time zones, but a number of those files are blank, and calling timezone('America/Los_Angeles') for example (LA file is empty) causes unpack to throw an exception.