BUG: fix segfault of fold (pandas-dev#33931) - WIP

Author: hasB4K

pandas/_libs/tslibs/c_timestamp.pxd

@@ -9,6 +9,7 @@ cdef class _Timestamp(datetime):
         int64_t value, nanosecond
         object freq
         list _date_attributes
+        bint fold
     cpdef bint _get_start_end_field(self, str field)
     cpdef _get_date_name_field(self, object field, object locale)
     cdef int64_t _maybe_convert_value_to_local(self)

pandas/_libs/tslibs/c_timestamp.pyx

@@ -196,7 +196,7 @@ cdef class _Timestamp(datetime):
 
         return datetime(self.year, self.month, self.day,
                         self.hour, self.minute, self.second,
-                        self.microsecond, self.tzinfo)
+                        self.microsecond, self.tzinfo, fold=self.fold)
 
     cpdef to_datetime64(self):
         """

pandas/_libs/tslibs/timestamps.pyx

@@ -46,7 +46,8 @@ cdef inline object create_timestamp_from_ts(int64_t value,
     cdef _Timestamp ts_base
     ts_base = _Timestamp.__new__(Timestamp, dts.year, dts.month,
                                  dts.day, dts.hour, dts.min,
-                                 dts.sec, dts.us, tz, fold=fold)
+                                 dts.sec, dts.us, tz)
+    ts_base.fold = fold
     ts_base.value = value
     ts_base.freq = freq
     ts_base.nanosecond = dts.ps // 1000
@@ -434,7 +435,7 @@ class Timestamp(_Timestamp):
                 month is None and day is None and hour is None and
                 minute is None and second is None and
                 microsecond is None and nanosecond is None and
-                tzinfo is None):
+                tzinfo is None and fold is None):
             return ts_input
         elif isinstance(ts_input, str):
             # User passed a date string to parse.

pandas/tests/indexes/datetimes/test_constructors.py

@@ -1011,6 +1011,7 @@ def test_timestamp_constructor_retain_fold(tz, fold):
     result = ts.fold
     expected = fold
     assert result == expected
+    assert ts.to_pydatetime().fold == expected
 
 
 @pytest.mark.parametrize("tz", ["dateutil/Europe/London"])