add test which uses unknown index

Author: MarcoGorelli

pandas-stubs/_libs/tslibs/timestamps.pyi

@@ -20,7 +20,6 @@ from _typing import TimeZones
 import numpy as np
 from pandas import (
     DatetimeIndex,
-    Index,
     TimedeltaIndex,
 )
 from pandas.core.series import (
@@ -168,31 +167,31 @@ class Timestamp(datetime, SupportsIndex):
     def __le__(self, other: Timestamp | datetime | np.datetime64) -> bool: ...  # type: ignore[misc]
     @overload
     def __le__(
-        self, other: Index[Timestamp] | npt.NDArray[np.datetime64]
+        self, other: DatetimeIndex | npt.NDArray[np.datetime64]
     ) -> np_ndarray_bool: ...
     @overload
     def __le__(self, other: TimestampSeries) -> Series[bool]: ...
     @overload  # type: ignore[override]
     def __lt__(self, other: Timestamp | datetime | np.datetime64) -> bool: ...  # type: ignore[misc]
     @overload
     def __lt__(
-        self, other: Index[Timestamp] | npt.NDArray[np.datetime64]
+        self, other: DatetimeIndex | npt.NDArray[np.datetime64]
     ) -> np_ndarray_bool: ...
     @overload
     def __lt__(self, other: TimestampSeries) -> Series[bool]: ...
     @overload  # type: ignore[override]
     def __ge__(self, other: Timestamp | datetime | np.datetime64) -> bool: ...  # type: ignore[misc]
     @overload
     def __ge__(
-        self, other: Index[Timestamp] | npt.NDArray[np.datetime64]
+        self, other: DatetimeIndex | npt.NDArray[np.datetime64]
     ) -> np_ndarray_bool: ...
     @overload
     def __ge__(self, other: TimestampSeries) -> Series[bool]: ...
     @overload  # type: ignore[override]
     def __gt__(self, other: Timestamp | datetime | np.datetime64) -> bool: ...  # type: ignore[misc]
     @overload
     def __gt__(
-        self, other: Index[Timestamp] | npt.NDArray[np.datetime64]
+        self, other: DatetimeIndex | npt.NDArray[np.datetime64]
     ) -> np_ndarray_bool: ...
     @overload
     def __gt__(self, other: TimestampSeries) -> Series[bool]: ...
@@ -233,15 +232,15 @@ class Timestamp(datetime, SupportsIndex):
     @overload
     def __eq__(self, other: TimestampSeries) -> Series[bool]: ...  # type: ignore[overload-overlap]
     @overload
-    def __eq__(self, other: npt.NDArray[np.datetime64] | Index[Timestamp]) -> np_ndarray_bool: ...  # type: ignore[overload-overlap]
+    def __eq__(self, other: npt.NDArray[np.datetime64] | DatetimeIndex) -> np_ndarray_bool: ...  # type: ignore[overload-overlap]
     @overload
     def __eq__(self, other: object) -> Literal[False]: ...
     @overload
     def __ne__(self, other: Timestamp | datetime | np.datetime64) -> bool: ...  # type: ignore[overload-overlap] # pyright: ignore[reportOverlappingOverload]
     @overload
     def __ne__(self, other: TimestampSeries) -> Series[bool]: ...  # type: ignore[overload-overlap]
     @overload
-    def __ne__(self, other: npt.NDArray[np.datetime64] | Index[Timestamp]) -> np_ndarray_bool: ...  # type: ignore[overload-overlap]
+    def __ne__(self, other: npt.NDArray[np.datetime64] | DatetimeIndex) -> np_ndarray_bool: ...  # type: ignore[overload-overlap]
     @overload
     def __ne__(self, other: object) -> Literal[True]: ...
     def __hash__(self) -> int: ...

tests/test_scalars.py

@@ -1261,6 +1261,8 @@ def test_timestamp_cmp() -> None:
     c_np_dt64 = np.datetime64(1, "ns")
     c_dt_datetime = dt.datetime(year=2000, month=1, day=1)
     c_datetimeindex = pd.DatetimeIndex(["2000-1-1"])
+    # DatetimeIndex, but the type checker detects it to be Index[Unknown].
+    c_unknown_index = pd.DataFrame({"a": [1]}, index=c_datetimeindex).index
     c_np_ndarray_dt64 = np_dt64_arr
     c_series_dt64: TimestampSeries = pd.Series([1, 2, 3], dtype="datetime64[ns]")
     c_series_timestamp = pd.Series(pd.DatetimeIndex(["2000-1-1"]))
@@ -1281,6 +1283,8 @@ def test_timestamp_cmp() -> None:
 
     check(assert_type(ts > c_datetimeindex, np_ndarray_bool), np.ndarray, np.bool_)
     check(assert_type(ts <= c_datetimeindex, np_ndarray_bool), np.ndarray, np.bool_)
+    check(assert_type(ts > c_unknown_index, np_ndarray_bool), np.ndarray, np.bool_)
+    check(assert_type(ts <= c_unknown_index, np_ndarray_bool), np.ndarray, np.bool_)
 
     check(assert_type(ts > c_np_ndarray_dt64, np_ndarray_bool), np.ndarray, np.bool_)
     check(assert_type(ts <= c_np_ndarray_dt64, np_ndarray_bool), np.ndarray, np.bool_)