From 0b17616d132d63479d3fdca2dd15cf65d9af9730 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Thu, 6 Nov 2025 15:03:01 +0000
Subject: [PATCH 01/10] type asof

---
 pandas-stubs/core/frame.pyi  | 6 +++++-
 pandas-stubs/core/series.pyi | 4 ++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index a3d6f70ab..331d60463 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -1844,7 +1844,11 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
         **kwargs: Any,
     ) -> Series[_bool]: ...
     @final
-    def asof(self, where, subset: _str | list[_str] | None = None) -> Self: ...
+    def asof(
+        self,
+        where: Scalar | AnyArrayLike | Sequence[Scalar],
+        subset: Hashable | list[Hashable] | None = None,
+    ) -> Self: ...
     @final
     def asfreq(
         self,
diff --git a/pandas-stubs/core/series.pyi b/pandas-stubs/core/series.pyi
index 32b6bc8a5..9b21960c4 100644
--- a/pandas-stubs/core/series.pyi
+++ b/pandas-stubs/core/series.pyi
@@ -1523,8 +1523,8 @@ class Series(IndexOpsMixin[S1], ElementOpsMixin[S1], NDFrame):
     @final
     def asof(
         self,
-        where: Scalar | Sequence[Scalar],
-        subset: _str | Sequence[_str] | None = None,
+        where: Scalar | AnyArrayLike | Sequence[Scalar],
+        subset: None = None,
     ) -> Scalar | Series[S1]: ...
     @overload
     def clip(  # pyright: ignore[reportOverlappingOverload]

From a05e17f70ee255624e5f07eee751b12676f4eb1b Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Thu, 6 Nov 2025 15:19:12 +0000
Subject: [PATCH 02/10] type setitem

---
 pandas-stubs/core/frame.pyi  | 68 +++++++++++++++++++++++++++++++++---
 pandas-stubs/core/series.pyi |  4 +--
 2 files changed, 65 insertions(+), 7 deletions(-)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index 331d60463..deb20a48b 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -37,6 +37,7 @@ from pandas import (
     Timestamp,
 )
 from pandas.core.arraylike import OpsMixin
+from pandas.core.base import IndexOpsMixin
 from pandas.core.generic import NDFrame
 from pandas.core.groupby.generic import DataFrameGroupBy
 from pandas.core.indexers import BaseIndexer
@@ -90,6 +91,7 @@ from pandas._typing import (
     ArrayLike,
     AstypeArg,
     Axes,
+    AxesData,
     Axis,
     AxisColumn,
     AxisIndex,
@@ -191,6 +193,8 @@ class _iLocIndexerFrame(_iLocIndexer, Generic[_T]):
             | tuple[slice]
         ),
     ) -> _T: ...
+
+    # Keep in sync with `DataFrame.__setitem__`
     def __setitem__(
         self,
         idx: (
@@ -203,7 +207,7 @@ class _iLocIndexerFrame(_iLocIndexer, Generic[_T]):
         ),
         value: (
             Scalar
-            | Series
+            | IndexOpsMixin
             | DataFrame
             | np.ndarray
             | NAType
@@ -267,6 +271,8 @@ class _LocIndexerFrame(_LocIndexer, Generic[_T]):
     ) -> Series: ...
     @overload
     def __getitem__(self, idx: tuple[Scalar, slice]) -> Series | _T: ...
+
+    # Keep in sync with `DataFrame.__setitem__`
     @overload
     def __setitem__(
         self,
@@ -278,7 +284,7 @@ class _LocIndexerFrame(_LocIndexer, Generic[_T]):
             | NAType
             | NaTType
             | ArrayLike
-            | Series
+            | IndexOpsMixin
             | DataFrame
             | list
             | Mapping[Hashable, Scalar | NAType | NaTType]
@@ -322,7 +328,7 @@ class _AtIndexerFrame(_AtIndexer):
             | NAType
             | NaTType
             | ArrayLike
-            | Series
+            | IndexOpsMixin
             | DataFrame
             | list
             | Mapping[Hashable, Scalar | NAType | NaTType]
@@ -794,7 +800,57 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
     def isetitem(
         self, loc: int | Sequence[int], value: Scalar | ArrayLike | list[Any]
     ) -> None: ...
-    def __setitem__(self, key, value) -> None: ...
+
+    # Keep in sync with `_iLocIndexerFrame.__setitem__`
+    @overload
+    def __setitem__(
+        self,
+        idx: (
+            int
+            | IndexType
+            | tuple[int, int]
+            | tuple[IndexType, int]
+            | tuple[IndexType, IndexType]
+            | tuple[int, IndexType]
+        ),
+        value: (
+            Scalar
+            | IndexOpsMixin
+            | DataFrame
+            | np.ndarray
+            | NAType
+            | NaTType
+            | Mapping[Hashable, Scalar | NAType | NaTType]
+            | None
+        ),
+    ) -> None: ...
+    # Keep in sync with `_LocIndexerFrame.__setitem__`
+    @overload
+    def __setitem__(
+        self,
+        idx: (
+            MaskType | StrLike | _IndexSliceTuple | list[ScalarT] | IndexingInt | slice
+        ),
+        value: (
+            Scalar
+            | NAType
+            | NaTType
+            | ArrayLike
+            | IndexOpsMixin
+            | DataFrame
+            | list
+            | Mapping[Hashable, Scalar | NAType | NaTType]
+            | None
+        ),
+    ) -> None: ...
+    @overload
+    def __setitem__(
+        self,
+        idx: tuple[_IndexSliceTuple, Hashable],
+        value: (
+            Scalar | NAType | NaTType | ArrayLike | IndexOpsMixin | list | dict | None
+        ),
+    ) -> None: ...
     @overload
     def query(
         self,
@@ -2398,7 +2454,9 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
         **kwargs: Any,
     ) -> Series: ...
     # Not actually positional, but used to handle removal of deprecated
-    def set_axis(self, labels, *, axis: Axis = ..., copy: _bool = ...) -> Self: ...
+    def set_axis(
+        self, labels: AxesData, *, axis: Axis = 0, copy: _bool = ...
+    ) -> Self: ...
     def skew(
         self,
         axis: Axis | None = ...,
diff --git a/pandas-stubs/core/series.pyi b/pandas-stubs/core/series.pyi
index 9b21960c4..8088df68b 100644
--- a/pandas-stubs/core/series.pyi
+++ b/pandas-stubs/core/series.pyi
@@ -535,14 +535,14 @@ class Series(IndexOpsMixin[S1], ElementOpsMixin[S1], NDFrame):
     @final
     def __getattr__(self, name: _str) -> S1: ...
 
-    # Keep in sync with `iLocIndexerSeries.__getitem__`
+    # Keep in sync with `_iLocIndexerSeries.__getitem__`
     @overload
     def __getitem__(self, idx: IndexingInt) -> S1: ...
     @overload
     def __getitem__(
         self, idx: Index | Series | slice | np_ndarray_anyint
     ) -> Series[S1]: ...
-    # Keep in sync with `LocIndexerSeries.__getitem__`
+    # Keep in sync with `_LocIndexerSeries.__getitem__`
     @overload
     def __getitem__(  # type: ignore[overload-overlap] # pyright: ignore[reportOverlappingOverload]
         self,

From b66d0c85a56f26b27985c9e4e8dc7651f710536a Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Thu, 6 Nov 2025 15:49:53 +0000
Subject: [PATCH 03/10] wip#

---
 pandas-stubs/core/frame.pyi    | 11 ++++++++++-
 pandas-stubs/core/indexing.pyi |  4 ++--
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index deb20a48b..c1b9c9e27 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -816,6 +816,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
         value: (
             Scalar
             | IndexOpsMixin
+            | Sequence[Scalar]
             | DataFrame
             | np.ndarray
             | NAType
@@ -837,6 +838,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
             | NaTType
             | ArrayLike
             | IndexOpsMixin
+            | Sequence[Scalar]
             | DataFrame
             | list
             | Mapping[Hashable, Scalar | NAType | NaTType]
@@ -848,7 +850,14 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
         self,
         idx: tuple[_IndexSliceTuple, Hashable],
         value: (
-            Scalar | NAType | NaTType | ArrayLike | IndexOpsMixin | list | dict | None
+            Scalar
+            | NAType
+            | NaTType
+            | ArrayLike
+            | IndexOpsMixin
+            | Sequence[Scalar]
+            | dict
+            | None
         ),
     ) -> None: ...
     @overload
diff --git a/pandas-stubs/core/indexing.pyi b/pandas-stubs/core/indexing.pyi
index 832e2618a..868d10afc 100644
--- a/pandas-stubs/core/indexing.pyi
+++ b/pandas-stubs/core/indexing.pyi
@@ -3,7 +3,7 @@ from typing import (
     TypeVar,
 )
 
-from pandas.core.indexes.api import Index
+from pandas.core.base import IndexOpsMixin
 
 from pandas._libs.indexing import _NDFrameIndexerBase
 from pandas._typing import (
@@ -13,7 +13,7 @@ from pandas._typing import (
 )
 
 _IndexSliceTuple: TypeAlias = tuple[
-    Index | MaskType | Scalar | list[ScalarT] | slice | tuple[Scalar, ...], ...
+    IndexOpsMixin | MaskType | Scalar | list[ScalarT] | slice | tuple[Scalar, ...], ...
 ]
 
 _IndexSliceUnion: TypeAlias = slice | _IndexSliceTuple

From 6c91caaee3f7de24455d273662ccd4519a2bc005 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Tue, 11 Nov 2025 15:02:00 +0000
Subject: [PATCH 04/10] fixup setitem

---
 pandas-stubs/core/frame.pyi | 8 ++++++++
 tests/test_frame.py         | 5 +++++
 2 files changed, 13 insertions(+)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index 1bc16cb18..dc39ca8c1 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -866,6 +866,14 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
             | None
         ),
     ) -> None: ...
+    # Extra cases not supported by  `_LocIndexerFrame.__setitem__` /
+    # `_iLocIndexerFrame.__setitem__`.
+    @overload
+    def __setitem__(
+        self,
+        idx: IndexOpsMixin | DataFrame,
+        value: Scalar | NAType | NaTType | ArrayLike | Series | list | dict | None,
+    ): ...
     @overload
     def query(
         self,
diff --git a/tests/test_frame.py b/tests/test_frame.py
index eb2960b0f..abe8db2ad 100644
--- a/tests/test_frame.py
+++ b/tests/test_frame.py
@@ -292,6 +292,11 @@ def test_types_setitem() -> None:
     df[5] = [5, 6]
     df[["col1", "col2"]] = [[1, 2], [3, 4]]
     df[s] = [5, 6]
+    df["col1":"col2"] = [5, 6]
+    df.loc[:, s] = [5, 6]
+    df[[0, 1]] = [5, 6]
+    df["col1"] = [5, 6]
+    df[df["col1"] > 1] = [5, 6, 7]
     df[a] = [[1, 2], [3, 4]]
     df[i] = [8, 9]
 

From 9538b55519b4803d0ac3f2f7dff47ea29f80cde1 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Tue, 11 Nov 2025 15:43:15 +0000
Subject: [PATCH 05/10] remove invalid case

---
 tests/test_frame.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tests/test_frame.py b/tests/test_frame.py
index abe8db2ad..53662dfbf 100644
--- a/tests/test_frame.py
+++ b/tests/test_frame.py
@@ -292,7 +292,6 @@ def test_types_setitem() -> None:
     df[5] = [5, 6]
     df[["col1", "col2"]] = [[1, 2], [3, 4]]
     df[s] = [5, 6]
-    df["col1":"col2"] = [5, 6]
     df.loc[:, s] = [5, 6]
     df[[0, 1]] = [5, 6]
     df["col1"] = [5, 6]

From 02f940a797f1f50527a066e93ae67966a802a6c3 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Tue, 11 Nov 2025 16:42:04 +0000
Subject: [PATCH 06/10] remove test case which adds extra columns (thus making
 subsequent tests fail)

---
 tests/test_frame.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tests/test_frame.py b/tests/test_frame.py
index 53662dfbf..63fa9e65e 100644
--- a/tests/test_frame.py
+++ b/tests/test_frame.py
@@ -293,7 +293,6 @@ def test_types_setitem() -> None:
     df[["col1", "col2"]] = [[1, 2], [3, 4]]
     df[s] = [5, 6]
     df.loc[:, s] = [5, 6]
-    df[[0, 1]] = [5, 6]
     df["col1"] = [5, 6]
     df[df["col1"] > 1] = [5, 6, 7]
     df[a] = [[1, 2], [3, 4]]

From f2ba8740518f6062ed9de09bd32fdd48ee6c8291 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Tue, 11 Nov 2025 18:39:41 +0000
Subject: [PATCH 07/10] use Sequence[Sequence[Scalar]]

---
 pandas-stubs/core/frame.pyi    | 38 +++++++++++++++++++++++++++-------
 pandas-stubs/core/indexing.pyi |  4 ++--
 2 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index dc39ca8c1..aa56ece07 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -292,7 +292,8 @@ class _LocIndexerFrame(_LocIndexer, Generic[_T]):
             | ArrayLike
             | IndexOpsMixin
             | DataFrame
-            | list
+            | Sequence[Scalar]
+            | Sequence[Sequence[Scalar]]
             | Mapping[Hashable, Scalar | NAType | NaTType]
             | None
         ),
@@ -301,7 +302,17 @@ class _LocIndexerFrame(_LocIndexer, Generic[_T]):
     def __setitem__(
         self,
         idx: tuple[_IndexSliceTuple, Hashable],
-        value: Scalar | NAType | NaTType | ArrayLike | Series | list | dict | None,
+        value: (
+            Scalar
+            | NAType
+            | NaTType
+            | ArrayLike
+            | Series
+            | Sequence[Scalar]
+            | Sequence[Sequence[Scalar]]
+            | Mapping[Hashable, Scalar | NAType | NaTType]
+            | None
+        ),
     ) -> None: ...
 
 class _iAtIndexerFrame(_iAtIndexer):
@@ -336,7 +347,8 @@ class _AtIndexerFrame(_AtIndexer):
             | ArrayLike
             | IndexOpsMixin
             | DataFrame
-            | list
+            | Sequence[Scalar]
+            | Sequence[Sequence[Scalar]]
             | Mapping[Hashable, Scalar | NAType | NaTType]
             | None
         ),
@@ -824,7 +836,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
             | IndexOpsMixin
             | Sequence[Scalar]
             | DataFrame
-            | np.ndarray
+            | np_ndarray
             | NAType
             | NaTType
             | Mapping[Hashable, Scalar | NAType | NaTType]
@@ -845,8 +857,8 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
             | ArrayLike
             | IndexOpsMixin
             | Sequence[Scalar]
+            | Sequence[Sequence[Scalar]]
             | DataFrame
-            | list
             | Mapping[Hashable, Scalar | NAType | NaTType]
             | None
         ),
@@ -862,7 +874,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
             | ArrayLike
             | IndexOpsMixin
             | Sequence[Scalar]
-            | dict
+            | Mapping[Hashable, Scalar | NAType | NaTType]
             | None
         ),
     ) -> None: ...
@@ -872,8 +884,18 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
     def __setitem__(
         self,
         idx: IndexOpsMixin | DataFrame,
-        value: Scalar | NAType | NaTType | ArrayLike | Series | list | dict | None,
-    ): ...
+        value: (
+            Scalar
+            | NAType
+            | NaTType
+            | ArrayLike
+            | Series
+            | Sequence[Scalar]
+            | Sequence[Sequence[Scalar]]
+            | Mapping[Hashable, Scalar | NAType | NaTType]
+            | None
+        ),
+    ) -> None: ...
     @overload
     def query(
         self,
diff --git a/pandas-stubs/core/indexing.pyi b/pandas-stubs/core/indexing.pyi
index 868d10afc..62fc3435a 100644
--- a/pandas-stubs/core/indexing.pyi
+++ b/pandas-stubs/core/indexing.pyi
@@ -1,3 +1,4 @@
+from collections.abc import Sequence
 from typing import (
     TypeAlias,
     TypeVar,
@@ -9,11 +10,10 @@ from pandas._libs.indexing import _NDFrameIndexerBase
 from pandas._typing import (
     MaskType,
     Scalar,
-    ScalarT,
 )
 
 _IndexSliceTuple: TypeAlias = tuple[
-    IndexOpsMixin | MaskType | Scalar | list[ScalarT] | slice | tuple[Scalar, ...], ...
+    IndexOpsMixin | MaskType | Scalar | Sequence[Scalar] | slice, ...
 ]
 
 _IndexSliceUnion: TypeAlias = slice | _IndexSliceTuple

From 57585129385494f0dc4ae5178ef92f9519f70c49 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Wed, 12 Nov 2025 10:56:34 +0000
Subject: [PATCH 08/10] re-sync

---
 pandas-stubs/core/frame.pyi | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index aa56ece07..da456d3cb 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -214,6 +214,7 @@ class _iLocIndexerFrame(_iLocIndexer, Generic[_T]):
         value: (
             Scalar
             | IndexOpsMixin
+            | Sequence[Scalar]
             | DataFrame
             | np_ndarray
             | NAType
@@ -291,9 +292,9 @@ class _LocIndexerFrame(_LocIndexer, Generic[_T]):
             | NaTType
             | ArrayLike
             | IndexOpsMixin
-            | DataFrame
             | Sequence[Scalar]
             | Sequence[Sequence[Scalar]]
+            | DataFrame
             | Mapping[Hashable, Scalar | NAType | NaTType]
             | None
         ),
@@ -307,7 +308,7 @@ class _LocIndexerFrame(_LocIndexer, Generic[_T]):
             | NAType
             | NaTType
             | ArrayLike
-            | Series
+            | IndexOpsMixin
             | Sequence[Scalar]
             | Sequence[Sequence[Scalar]]
             | Mapping[Hashable, Scalar | NAType | NaTType]
@@ -874,6 +875,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
             | ArrayLike
             | IndexOpsMixin
             | Sequence[Scalar]
+            | Sequence[Sequence[Scalar]]
             | Mapping[Hashable, Scalar | NAType | NaTType]
             | None
         ),

From 6dc4c965b80896ff0258b041bc2243a9a11b4865 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Wed, 12 Nov 2025 11:00:38 +0000
Subject: [PATCH 09/10] widen Series to IndexOpsMixin

---
 pandas-stubs/core/frame.pyi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index da456d3cb..3b9251752 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -891,7 +891,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
             | NAType
             | NaTType
             | ArrayLike
-            | Series
+            | IndexOpsMixin
             | Sequence[Scalar]
             | Sequence[Sequence[Scalar]]
             | Mapping[Hashable, Scalar | NAType | NaTType]

From 16a2e683a35f823d0c2a2ae6408eb3c0108f9a30 Mon Sep 17 00:00:00 2001
From: Marco Gorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Wed, 12 Nov 2025 12:15:00 +0000
Subject: [PATCH 10/10] remove deprecated `copy`

---
 pandas-stubs/core/frame.pyi | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/pandas-stubs/core/frame.pyi b/pandas-stubs/core/frame.pyi
index 3b9251752..da31cff03 100644
--- a/pandas-stubs/core/frame.pyi
+++ b/pandas-stubs/core/frame.pyi
@@ -2555,9 +2555,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
         **kwargs: Any,
     ) -> Series: ...
     # Not actually positional, but used to handle removal of deprecated
-    def set_axis(
-        self, labels: AxesData, *, axis: Axis = 0, copy: _bool = ...
-    ) -> Self: ...
+    def set_axis(self, labels: AxesData, *, axis: Axis = 0) -> Self: ...
     def skew(
         self,
         axis: Axis | None = ...,