Fixed #5470 -- Fixed the 'Z' time format marker in templates to handl…

…e timezones west of UTC. Thanks, Paul Lanier.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6275 bcc190cf-cafb-0310-a4f2-bffc1f526a37

AUTHORS

@@ -182,6 +182,7 @@ answer newbie questions, and generally made Django that much better:
     lakin.wecker@gmail.com
     Nick Lane <nick.lane.au@gmail.com>
     Stuart Langridge <http://www.kryogenix.org/>
+    Paul Lanier <planier@google.com>
     Nicola Larosa <nico@teknico.net>
     Eugene Lazutkin <http://lazutkin.com/blog/>
     Jeong-Min Lee <falsetru@gmail.com>

django/utils/dateformat.py

@@ -248,10 +248,15 @@ def z(self):
         return doy
 
     def Z(self):
-        """Time zone offset in seconds (i.e. '-43200' to '43200'). The offset
-        for timezones west of UTC is always negative, and for those east of UTC
-        is always positive."""
-        return self.timezone.utcoffset(self.data).seconds
+        """
+        Time zone offset in seconds (i.e. '-43200' to '43200'). The offset for
+        timezones west of UTC is always negative, and for those east of UTC is
+        always positive.
+        """
+        offset = self.timezone.utcoffset(self.data)
+        # Only days can be negative, so negative offsets have days=-1 and
+        # seconds positive. Positive offsets have days=0
+        return offset.days * 86400 + offset.seconds
 
 def format(value, format_string):
     "Convenience function"