BUG: Bug in pickling of a non-regular freq DatetimeIndex #11002

doc/source/whatsnew/v0.17.0.txt

@@ -894,7 +894,7 @@ Bug Fixes
 - Bug in clearing the cache on ``DataFrame.pop`` and a subsequent inplace op (:issue:`10912`)
 - Bug in indexing with a mixed-integer ``Index`` causing an ``ImportError`` (:issue:`10610`)
 - Bug in ``Series.count`` when index has nulls (:issue:`10946`)
-
+- Bug in pickling of a non-regular freq ``DatetimeIndex`` (:issue:`11002`)
 - Bug causing ``DataFrame.where`` to not respect the ``axis`` parameter when the frame has a symmetric shape. (:issue:`9736`)
 
 - Bug in ``Table.select_column`` where name is not preserved (:issue:`10392`)

pandas/tseries/index.py

@@ -120,7 +120,8 @@ def _new_DatetimeIndex(cls, d):
     # data are already in UTC
     # so need to localize
     tz = d.pop('tz',None)
-    result = cls.__new__(cls, **d)
+
+    result = cls.__new__(cls, verify_integrity=False, **d)
     if tz is not None:
         result = result.tz_localize('UTC').tz_convert(tz)
     return result

pandas/tseries/tests/test_timeseries.py

@@ -2142,8 +2142,8 @@ def test_period_resample_with_local_timezone_dateutil(self):
 
 
     def test_pickle(self):
-        #GH4606
 
+        # GH4606
         p = self.round_trip_pickle(NaT)
         self.assertTrue(p is NaT)
 
@@ -2153,6 +2153,11 @@ def test_pickle(self):
         self.assertTrue(idx_p[1] is NaT)
         self.assertTrue(idx_p[2] == idx[2])
 
+        # GH11002
+        # don't infer freq
+        idx = date_range('1750-1-1', '2050-1-1', freq='7D')
+        idx_p = self.round_trip_pickle(idx)
+        tm.assert_index_equal(idx, idx_p)
 
 def _simple_ts(start, end, freq='D'):
     rng = date_range(start, end, freq=freq)