Fix pickling of tzoffset

Fixes gitpython-developers#650

Author: xhochy

git/objects/util.py

@@ -105,6 +105,9 @@ def __init__(self, secs_west_of_utc, name=None):
         self._offset = timedelta(seconds=-secs_west_of_utc)
         self._name = name or 'fixed'
 
+    def __reduce__(self):
+        return tzoffset, (-self._offset.total_seconds(), self._name)
+
     def utcoffset(self, dt):
         return self._offset
 

git/test/test_util.py

@@ -274,3 +274,9 @@ def test_from_timestamp(self):
         # Wrong offset: UTC-9000, should return datetime + tzoffset(UTC)
         altz = utctz_to_altz('-9000')
         self.assertEqual(datetime.fromtimestamp(1522827734, tzoffset(0)), from_timestamp(1522827734, altz))
+
+    def test_pickle_tzoffset(self):
+        t1 = tzoffset(555)
+        t2 = pickle.loads(pickle.dumps(t1))
+        self.assertEqual(t1._offset, t2._offset)
+        self.assertEqual(t1._name, t2._name)