Added back support for reading old DateTime pickles without a `_micro…

…s` value.

CHANGES.txt

@@ -4,6 +4,8 @@ Changelog
 3.0 (unreleased)
 ----------------
 
+- Added back support for reading old DateTime pickles without a `_micros` value.
+
 - Avoid storing `_t` representing the time as a float in seconds since the
   epoch, as we already have `_micros` doing the same as a long. Memory use is
   down to about 300 bytes per DateTime instance.

src/DateTime/DateTime.py

@@ -442,7 +442,9 @@ def __init__(self, *args, **kw):
     def __getstate__(self):
         # We store a float of _micros, instead of the _micros long, as we most
         # often don't have any sub-second resolution and can save those bytes
-        return (self._micros / 1000000.0, self._timezone_naive, self._tz)
+        return (self._micros / 1000000.0,
+            getattr(self, '_timezone_naive', False),
+            self._tz)
 
     def __setstate__(self, value):
         if isinstance(value, tuple):
@@ -453,6 +455,11 @@ def __setstate__(self, value):
             for k, v in value.items():
                 if k in self.__slots__:
                     setattr(self, k, v)
+            # BBB: support for very old DateTime pickles
+            if '_micros' not in value:
+                self._micros = long(value['_t'] * 1000000)
+            if '_timezone_naive' not in value:
+                self._timezone_naive = False
 
     def _parse_args(self, *args, **kw):
         """Return a new date-time object.

src/DateTime/tests/testDateTime.py

@@ -237,6 +237,23 @@ def test_pickle_old(self):
         for key in DateTime.__slots__:
             self.assertEqual(getattr(dt, key), getattr(new, key))
 
+    def test_pickle_old_without_micros(self):
+        dt = DateTime('2002/5/2 8:00am GMT+0')
+        data = ('(cDateTime.DateTime\nDateTime\nq\x01Noq\x02}q\x03(U\x05_amonq'
+            '\x04U\x03Mayq\x05U\x05_adayq\x06U\x03Thuq\x07U\x05_pmonq\x08h'
+            '\x05U\x05_hourq\tK\x08U\x05_fmonq\nh\x05U\x05_pdayq\x0bU'
+            '\x04Thu.q\x0cU\x05_fdayq\rU\x08Thursdayq\x0eU\x03_pmq\x0fU'
+            '\x02amq\x10U\x02_tq\x11GA\xcehy\x00\x00\x00\x00U\x07_minuteq'
+            '\x12K\x00U\x02_dq\x13G@\xe2\x12j\xaa\xaa\xaa\xabU\x07_secondq'
+            '\x14G\x00\x00\x00\x00\x00\x00\x00\x00U\x03_tzq\x15U\x05GMT+0q'
+            '\x16U\x06_monthq\x17K\x05U\x0f_timezone_naiveq\x18I00\nU'
+            '\x04_dayq\x19K\x02U\x05_yearq\x1aM\xd2\x07U\x08_nearsecq'
+            '\x1bG\x00\x00\x00\x00\x00\x00\x00\x00U\x07_pmhourq\x1cK\x08U'
+            '\n_dayoffsetq\x1dK\x04U\x04timeq\x1eG?\xd5UUUV\x00\x00ub.')
+        new = cPickle.loads(data)
+        for key in DateTime.__slots__:
+            self.assertEqual(getattr(dt, key), getattr(new, key))
+
     def testTZ2(self):
         # Time zone manipulation test 2
         dt = DateTime()