BUG: pandas.date_range() raises NonExistentTimeError despite nonexistent="shift_forward" when crossing DST boundaries #62602

pandas/_libs/tslibs/timestamps.pyi

@@ -23,7 +23,11 @@ from pandas._libs.tslibs import (
     Tick,
     Timedelta,
 )
-from pandas._typing import TimestampNonexistent
+from pandas._typing import (
+    TimeAmbiguous,
+    TimeNonexistent,
+    TimestampNonexistent,
+)
 
 _TimeZones: TypeAlias = str | _tzinfo | None | int
 
@@ -191,7 +195,11 @@ class Timestamp(datetime):
         ambiguous: bool | Literal["raise", "NaT"] = ...,
         nonexistent: TimestampNonexistent = ...,
     ) -> Self: ...
-    def normalize(self) -> Self: ...
+    def normalize(
+        self,
+        ambiguous: TimeAmbiguous = ...,
+        nonexistent: TimeNonexistent = ...,
+    ) -> Self: ...
     # TODO: round/floor/ceil could return NaT?
     def round(
         self,

pandas/_libs/tslibs/timestamps.pyx

@@ -1308,7 +1308,10 @@ cdef class _Timestamp(ABCTimestamp):
     # -----------------------------------------------------------------
     # Transformation Methods
 
-    def normalize(self) -> "Timestamp":
+    def normalize(self,
+                  ambiguous: TimeAmbiguous = "raise",
+                  nonexistent: TimeNonexistent = "raise"
+                  ) -> "Timestamp":
         """
         Normalize Timestamp to midnight, preserving tz information.
 
@@ -1346,7 +1349,7 @@ cdef class _Timestamp(ABCTimestamp):
                 "Cannot normalize Timestamp without integer overflow"
             ) from err
         ts = type(self)._from_value_and_reso(normalized, reso=self._creso, tz=None)
-        return ts.tz_localize(self.tzinfo)
+        return ts.tz_localize(self.tzinfo, ambiguous=ambiguous, nonexistent=nonexistent)
 
     # -----------------------------------------------------------------
     # Pickle Methods

pandas/core/arrays/datetimes.py

@@ -447,7 +447,9 @@ def _generate_range(
             end = end.as_unit(unit, round_ok=False)
 
         left_inclusive, right_inclusive = validate_inclusive(inclusive)
-        start, end = _maybe_normalize_endpoints(start, end, normalize)
+        start, end = _maybe_normalize_endpoints(
+            start, end, normalize, ambiguous, nonexistent
+        )
         tz = _infer_tz_from_endpoints(start, end, tz)
 
         if tz is not None:
@@ -2878,14 +2880,18 @@ def _infer_tz_from_endpoints(
 
 
 def _maybe_normalize_endpoints(
-    start: _TimestampNoneT1, end: _TimestampNoneT2, normalize: bool
+    start: _TimestampNoneT1,
+    end: _TimestampNoneT2,
+    normalize: bool,
+    ambiguous: TimeAmbiguous = "raise",
+    nonexistent: TimeNonexistent = "raise",
 ) -> tuple[_TimestampNoneT1, _TimestampNoneT2]:
     if normalize:
         if start is not None:
-            start = start.normalize()
+            start = start.normalize(ambiguous=ambiguous, nonexistent=nonexistent)
 
         if end is not None:
-            end = end.normalize()
+            end = end.normalize(ambiguous=ambiguous, nonexistent=nonexistent)
 
     return start, end
 

pandas/tests/arrays/test_datetimes.py

@@ -844,3 +844,25 @@ def test_factorize_sort_without_freq():
     tda = dta - dta[0]
     with pytest.raises(NotImplementedError, match=msg):
         tda.factorize(sort=True)
+
+
+def test_date_range_dst_boundries():
+    # GH#62602
+    start = pd.Timestamp("2024-04-26 01:00:00", tz="Africa/Cairo")
+    end = pd.Timestamp("2024-04-27 00:00:00", tz="Africa/Cairo")
+    tz = "Africa/Cairo"
+    freq = "D"
+
+    full_range = pd.date_range(
+        start=start,
+        end=end,
+        freq=freq,
+        tz=tz,
+        nonexistent="shift_forward",
+        ambiguous=True,
+        normalize=True,
+    )
+    expected = pd.DatetimeIndex(
+        ["2024-04-26 01:00:00+03:00"], dtype="datetime64[ns, Africa/Cairo]", freq="D"
+    )
+    assert full_range == expected