Fixed pickling of FixedOffsetTimezone objects

I have also verified that the fixed class can unpickle instance pickled with
the buggy one and viceversa.

Fixes ticket #135.

NEWS

@@ -24,6 +24,7 @@ What's new in psycopg 2.4.6
   - connect() raises an exception instead of swallowing keyword arguments
     when a connection string is specified as well (ticket #131).
   - Discard any result produced by 'executemany()' (ticket #133).
+  - Fixed pickling of FixedOffsetTimezone objects (ticket #135).
   - 'errorcodes' map updated to PostgreSQL 9.2.
 
 

lib/tz.py

@@ -72,6 +72,10 @@ class FixedOffsetTimezone(datetime.tzinfo):
         return "psycopg2.tz.FixedOffsetTimezone(offset=%r, name=%r)" \
             % (offset_mins, self._name)
 
+    def __getinitargs__(self):
+        offset_mins = self._offset.seconds // 60 + self._offset.days * 24 * 60
+        return (offset_mins, self._name)
+
     def utcoffset(self, dt):
         return self._offset
 
@@ -86,7 +90,7 @@ class FixedOffsetTimezone(datetime.tzinfo):
                 return "%+03d:%d" % (hours, minutes)
             else:
                 return "%+03d" % hours
-            
+
     def dst(self, dt):
         return ZERO
 
@@ -103,7 +107,6 @@ class LocalTimezone(datetime.tzinfo):
 
     This is the exact implementation from the Python 2.3 documentation.
     """
-    
     def utcoffset(self, dt):
         if self._isdst(dt):
             return DSTOFFSET

tests/test_dates.py

@@ -539,6 +539,24 @@ class FixedOffsetTimezoneTests(unittest.TestCase):
         self.assert_(FixedOffsetTimezone(9 * 60) is not FixedOffsetTimezone(9 * 60, 'FOO'))
         self.assert_(FixedOffsetTimezone(name='FOO') is not FixedOffsetTimezone(9 * 60, 'FOO'))
 
+    def test_pickle(self):
+        # ticket #135
+        import pickle
+
+        tz11 = FixedOffsetTimezone(60)
+        tz12 = FixedOffsetTimezone(120)
+        for proto in [-1, 0, 1, 2]:
+            tz21, tz22 = pickle.loads(pickle.dumps([tz11, tz12], proto))
+            self.assertEqual(tz11, tz21)
+            self.assertEqual(tz12, tz22)
+
+        tz11 = FixedOffsetTimezone(60, name='foo')
+        tz12 = FixedOffsetTimezone(120, name='bar')
+        for proto in [-1, 0, 1, 2]:
+            tz21, tz22 = pickle.loads(pickle.dumps([tz11, tz12], proto))
+            self.assertEqual(tz11, tz21)
+            self.assertEqual(tz12, tz22)
+
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)