[Findit] Add local git parsers.

appengine/findit/common/test/time_util_test.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import mock
 import unittest
 
 from common import time_util
 from datetime import datetime
 from datetime import timedelta
@@ skipping 34 matching lines @@
     self.assertEqual('expected',
                      time_util.GetDatetimeInTimezone('PST', mocked_datetime))
     mocked_pytz_module.timezone.assert_called_with('PST')
 
   def testFormatDuration(self):
     date1 = datetime(2016, 5, 1, 1, 1, 1)
     date2 = datetime(2016, 5, 1, 1, 2, 1)
     self.assertIsNone(time_util.FormatDuration(None, date1))
     self.assertIsNone(time_util.FormatDuration(date1, None))
     self.assertEqual('00:01:00', time_util.FormatDuration(date1, date2))
+
+  def testTimeZoneInfo(self):
+    naive_time = datetime(2016, 9, 1, 10, 0, 0)
+
+    tz = time_util.TimeZoneInfo('+0800')
+    self.assertEqual(tz.utcoffset, timedelta(minutes=480))

[stgao, 2016/10/22 00:39:16]

+chanli: is this correct? I remembered you worked on some similar code?

[Sharu Jiang, 2016/10/25 00:36:19]

I just found out I can use 'TZ=UTC git log --date=local' to let git do the
conversion, the timezone is no longer needed.

+    self.assertEqual(tz.LocalToUTC(naive_time), datetime(2016, 9, 1, 18, 0, 0))
+
+    tz_negative = time_util.TimeZoneInfo('-0700')
+    self.assertEqual(tz_negative.utcoffset, timedelta(minutes=-420))
+    self.assertEqual(tz_negative.LocalToUTC(naive_time),
+                     datetime(2016, 9, 1, 3, 0, 0))
+
+