Fix wraparound/overflow in date_range

doc/source/whatsnew/v0.23.0.txt

@@ -716,7 +716,7 @@ Datetimelike
 - Bug in :class:`Timestamp` and :func:`to_datetime` where a string representing a barely out-of-bounds timestamp would be incorrectly rounded down instead of raising ``OutOfBoundsDatetime`` (:issue:`19382`)
 - Bug in :func:`Timestamp.floor` :func:`DatetimeIndex.floor` where time stamps far in the future and past were not rounded correctly (:issue:`19206`)
 - Bug in :func:`to_datetime` where passing an out-of-bounds datetime with ``errors='coerce'`` and ``utc=True`` would raise ``OutOfBoundsDatetime`` instead of parsing to ``NaT`` (:issue:`19612`)
--
+- Bug in :func:`date_range` with frequency of ``Day`` or higher where dates sufficiently far in the future could wrap around to the past instead of raising ``OutOfBoundsDatetime`` (:issue:`19740`)
 
 Timezones
 ^^^^^^^^^

pandas/core/indexes/datetimes.py

@@ -2137,11 +2137,11 @@ def _generate_regular_range(start, end, periods, offset):
             tz = start.tz
         elif start is not None:
             b = Timestamp(start).value
-            e = b + np.int64(periods) * stride
+            e = _reraise_overflow_as_oob(b, periods, stride, side='start')
             tz = start.tz
         elif end is not None:
             e = Timestamp(end).value + stride
-            b = e - np.int64(periods) * stride
+            b = _reraise_overflow_as_oob(e, periods, stride, side='end')
             tz = end.tz
         else:
             raise ValueError("at least 'start' or 'end' should be specified "
@@ -2166,6 +2166,44 @@ def _generate_regular_range(start, end, periods, offset):
     return data
 
 
+def _reraise_overflow_as_oob(endpoint, periods, stride, side='start'):
+    """
+    Calculate the second endpoint for passing to np.arange, checking
+    to avoid an integer overflow.  Catch OverflowError and re-raise
+    as OutOfBoundsDatetime.
+
+    Parameters
+    ----------
+    endpoint : int
+    periods : int
+    stride : int
+    side : {'start', 'end'}
+
+    Returns
+    -------
+    other_end : int
+
+    Raises
+    ------
+    OutOfBoundsDatetime
+    """
+    # GH#19740 raise instead of incorrectly wrapping around
+    assert side in ['start', 'end']
+    if side == 'end':
+        stride *= -1
+
+    try:
+        other_end = checked_add_with_arr(np.int64(endpoint),
+                                         np.int64(periods) * stride)
+    except OverflowError:
+        raise libts.OutOfBoundsDatetime('Cannot generate range with '
+                                        '{side}={endpoint} and '
+                                        'periods={periods}'
+                                        .format(side=side, endpoint=endpoint,
+                                                periods=periods))
+    return other_end
+
+
 def date_range(start=None, end=None, periods=None, freq='D', tz=None,
                normalize=False, name=None, closed=None, **kwargs):
     """

pandas/tests/indexes/datetimes/test_date_range.py

@@ -13,6 +13,7 @@
 import pandas.util.testing as tm
 import pandas.util._test_decorators as td
 from pandas import compat
+from pandas.errors import OutOfBoundsDatetime
 from pandas import date_range, bdate_range, offsets, DatetimeIndex, Timestamp
 from pandas.tseries.offsets import (generate_range, CDay, BDay, DateOffset,
                                     MonthEnd, prefix_mapping)
@@ -78,6 +79,12 @@ def test_date_range_timestamp_equiv_preserve_frequency(self):
 
 
 class TestDateRanges(TestData):
+    def test_date_range_out_of_bounds(self):
+        # GH#19740
+        with pytest.raises(OutOfBoundsDatetime):
+            date_range('2016-01-01', periods=100000, freq='D')
+        with pytest.raises(OutOfBoundsDatetime):
+            date_range(end='1763-10-12', periods=100000, freq='D')
 
     def test_date_range_gen_error(self):
         rng = date_range('1/1/2000 00:00', '1/1/2000 00:18', freq='5min')