From 5cc32057b672e89cbbeef9399dea077b64ae2e6b Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Tue, 2 Aug 2022 10:35:37 -0700
Subject: [PATCH 1/9] ENH: copy keyword to set_axis

---
 doc/source/whatsnew/v1.5.0.rst              |  1 +
 pandas/core/frame.py                        | 33 +++++++++++---
 pandas/core/generic.py                      | 50 +++++++++++++++++----
 pandas/core/series.py                       | 31 ++++++++++---
 pandas/tests/frame/methods/test_set_axis.py | 31 +++++++++++++
 5 files changed, 128 insertions(+), 18 deletions(-)

diff --git a/doc/source/whatsnew/v1.5.0.rst b/doc/source/whatsnew/v1.5.0.rst
index 6e38024e02f36..55c31fe1c77f2 100644
--- a/doc/source/whatsnew/v1.5.0.rst
+++ b/doc/source/whatsnew/v1.5.0.rst
@@ -279,6 +279,7 @@ Other enhancements
 - :class:`Series` reducers (e.g. ``min``, ``max``, ``sum``, ``mean``) will now successfully operate when the dtype is numeric and ``numeric_only=True`` is provided; previously this would raise a ``NotImplementedError`` (:issue:`47500`)
 - :meth:`RangeIndex.union` now can return a :class:`RangeIndex` instead of a :class:`Int64Index` if the resulting values are equally spaced (:issue:`47557`, :issue:`43885`)
 - :meth:`DataFrame.compare` now accepts an argument ``result_names`` to allow the user to specify the result's names of both left and right DataFrame which are being compared. This is by default ``'self'`` and ``'other'`` (:issue:`44354`)
+- Added ``copy`` keyword to :meth:`Series.set_axis` and :meth:`DataFrame.set_axis` to allow user to set axis on a new object without necessarily copying the underlying data (:issue:`??`)
 
 .. ---------------------------------------------------------------------------
 .. _whatsnew_150.notable_bug_fixes:
diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index f0b7349f74f13..2784da605e339 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -5010,17 +5010,34 @@ def align(
 
     @overload
     def set_axis(
-        self, labels, *, axis: Axis = ..., inplace: Literal[False] = ...
+        self,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: Literal[False] = ...,
+        copy: bool | lib.NoDefault = ...,
     ) -> DataFrame:
         ...
 
     @overload
-    def set_axis(self, labels, *, axis: Axis = ..., inplace: Literal[True]) -> None:
+    def set_axis(
+        self,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: Literal[True],
+        copy: bool | lib.NoDefault = ...,
+    ) -> None:
         ...
 
     @overload
     def set_axis(
-        self, labels, *, axis: Axis = ..., inplace: bool = ...
+        self,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: bool = ...,
+        copy: bool | lib.NoDefault = ...,
     ) -> DataFrame | None:
         ...
 
@@ -5064,8 +5081,14 @@ def set_axis(
         see_also_sub=" or columns",
     )
     @Appender(NDFrame.set_axis.__doc__)
-    def set_axis(self, labels, axis: Axis = 0, inplace: bool = False):
-        return super().set_axis(labels, axis=axis, inplace=inplace)
+    def set_axis(
+        self,
+        labels,
+        axis: Axis = 0,
+        inplace: bool = False,
+        copy: bool | lib.NoDefault = lib.no_default,
+    ):
+        return super().set_axis(labels, axis=axis, inplace=inplace, copy=copy)
 
     @Substitution(**_shared_doc_kwargs)
     @Appender(NDFrame.reindex.__doc__)
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 7352ad2a4985d..d8393ea9f435c 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -708,23 +708,43 @@ def size(self) -> int:
 
     @overload
     def set_axis(
-        self: NDFrameT, labels, *, axis: Axis = ..., inplace: Literal[False] = ...
+        self: NDFrameT,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: Literal[False] = ...,
+        copy: bool_t | lib.NoDefault = ...,
     ) -> NDFrameT:
         ...
 
     @overload
-    def set_axis(self, labels, *, axis: Axis = ..., inplace: Literal[True]) -> None:
+    def set_axis(
+        self,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: Literal[True],
+        copy: bool_t | lib.NoDefault = ...,
+    ) -> None:
         ...
 
     @overload
     def set_axis(
-        self: NDFrameT, labels, *, axis: Axis = ..., inplace: bool_t = ...
+        self: NDFrameT,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: bool_t | lib.NoDefault = ...,
     ) -> NDFrameT | None:
         ...
 
     @deprecate_nonkeyword_arguments(version=None, allowed_args=["self", "labels"])
     def set_axis(
-        self: NDFrameT, labels, axis: Axis = 0, inplace: bool_t = False
+        self: NDFrameT,
+        labels,
+        axis: Axis = 0,
+        inplace: bool_t = False,
+        copy: bool_t | lib.NoDefault = lib.no_default,
     ) -> NDFrameT | None:
         """
         Assign desired index to given axis.
@@ -744,6 +764,11 @@ def set_axis(
         inplace : bool, default False
             Whether to return a new %(klass)s instance.
 
+        copy : bool, default True
+            Whether to make a copy of the underlying data.
+
+            .. versionadded:: 1.5.0
+
         Returns
         -------
         renamed : %(klass)s or None
@@ -753,16 +778,25 @@ def set_axis(
         --------
         %(klass)s.rename_axis : Alter the name of the index%(see_also_sub)s.
         """
+        if inplace:
+            if copy is True:
+                raise ValueError("Cannot specify both inplace=True and copy=True")
+            copy = False
+        elif copy is lib.no_default:
+            copy = True
+
         self._check_inplace_and_allows_duplicate_labels(inplace)
-        return self._set_axis_nocheck(labels, axis, inplace)
+        return self._set_axis_nocheck(labels, axis, inplace, copy=copy)
 
     @final
-    def _set_axis_nocheck(self, labels, axis: Axis, inplace: bool_t):
+    def _set_axis_nocheck(self, labels, axis: Axis, inplace: bool_t, copy: bool_t):
         # NDFrame.rename with inplace=False calls set_axis(inplace=True) on a copy.
         if inplace:
             setattr(self, self._get_axis_name(axis), labels)
         else:
-            obj = self.copy()
+            # With copy=False, we create a new object but don't copy the
+            #  underlying data.
+            obj = self.copy(deep=copy)
             obj.set_axis(labels, axis=axis, inplace=True)
             return obj
 
@@ -1050,7 +1084,7 @@ def _rename(
                     raise KeyError(f"{missing_labels} not found in axis")
 
             new_index = ax._transform_index(f, level=level)
-            result._set_axis_nocheck(new_index, axis=axis_no, inplace=True)
+            result._set_axis_nocheck(new_index, axis=axis_no, inplace=True, copy=False)
             result._clear_item_cache()
 
         if inplace:
diff --git a/pandas/core/series.py b/pandas/core/series.py
index 765bf9f7e04f1..172f90c52ba99 100644
--- a/pandas/core/series.py
+++ b/pandas/core/series.py
@@ -4926,17 +4926,34 @@ def rename(
 
     @overload
     def set_axis(
-        self, labels, *, axis: Axis = ..., inplace: Literal[False] = ...
+        self,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: Literal[False] = ...,
+        copy: bool | lib.NoDefault = ...,
     ) -> Series:
         ...
 
     @overload
-    def set_axis(self, labels, *, axis: Axis = ..., inplace: Literal[True]) -> None:
+    def set_axis(
+        self,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: Literal[True],
+        copy: bool | lib.NoDefault = ...,
+    ) -> None:
         ...
 
     @overload
     def set_axis(
-        self, labels, *, axis: Axis = ..., inplace: bool = ...
+        self,
+        labels,
+        *,
+        axis: Axis = ...,
+        inplace: bool = ...,
+        copy: bool | lib.NoDefault = ...,
     ) -> Series | None:
         ...
 
@@ -4968,9 +4985,13 @@ def set_axis(
     )
     @Appender(NDFrame.set_axis.__doc__)
     def set_axis(  # type: ignore[override]
-        self, labels, axis: Axis = 0, inplace: bool = False
+        self,
+        labels,
+        axis: Axis = 0,
+        inplace: bool = False,
+        copy: bool | lib.NoDefault = lib.no_default,
     ) -> Series | None:
-        return super().set_axis(labels, axis=axis, inplace=inplace)
+        return super().set_axis(labels, axis=axis, inplace=inplace, copy=copy)
 
     # error: Cannot determine type of 'reindex'
     @doc(
diff --git a/pandas/tests/frame/methods/test_set_axis.py b/pandas/tests/frame/methods/test_set_axis.py
index 3284243ddac48..2bf612895aa1e 100644
--- a/pandas/tests/frame/methods/test_set_axis.py
+++ b/pandas/tests/frame/methods/test_set_axis.py
@@ -24,6 +24,37 @@ def test_set_axis(self, obj):
         result = obj.set_axis(new_index, axis=0, inplace=False)
         tm.assert_equal(expected, result)
 
+    def test_set_axis_copy(self, obj):
+        # Test copy keyword
+        new_index = list("abcd")[: len(obj)]
+
+        expected = obj.copy()
+        expected.index = new_index
+
+        with pytest.raises(
+            ValueError, match="Cannot specify both inplace=True and copy=True"
+        ):
+            obj.set_axis(new_index, axis=0, inplace=True, copy=True)
+
+        result = obj.set_axis(new_index, axis=0, copy=True)
+        tm.assert_equal(expected, result)
+        assert result is not obj
+        # check we DID make a copy
+        assert not tm.shares_memory(result, obj)
+
+        result = obj.set_axis(new_index, axis=0, copy=False)
+        tm.assert_equal(expected, result)
+        assert result is not obj
+        # check we did NOT make a copy
+        assert tm.shares_memory(result, obj)
+
+        # copy defaults to True
+        result = obj.set_axis(new_index, axis=0)
+        tm.assert_equal(expected, result)
+        assert result is not obj
+        # check we DID make a copy
+        assert not tm.shares_memory(result, obj)
+
     @pytest.mark.parametrize("axis", [0, "index", 1, "columns"])
     def test_set_axis_inplace_axis(self, axis, obj):
         # GH#14636

From b2214920dadeadc7a120c34d0491ea23446f762a Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Tue, 2 Aug 2022 10:37:28 -0700
Subject: [PATCH 2/9] GH ref

---
 doc/source/whatsnew/v1.5.0.rst              | 2 +-
 pandas/tests/frame/methods/test_set_axis.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/doc/source/whatsnew/v1.5.0.rst b/doc/source/whatsnew/v1.5.0.rst
index 55c31fe1c77f2..03007355e68e4 100644
--- a/doc/source/whatsnew/v1.5.0.rst
+++ b/doc/source/whatsnew/v1.5.0.rst
@@ -279,7 +279,7 @@ Other enhancements
 - :class:`Series` reducers (e.g. ``min``, ``max``, ``sum``, ``mean``) will now successfully operate when the dtype is numeric and ``numeric_only=True`` is provided; previously this would raise a ``NotImplementedError`` (:issue:`47500`)
 - :meth:`RangeIndex.union` now can return a :class:`RangeIndex` instead of a :class:`Int64Index` if the resulting values are equally spaced (:issue:`47557`, :issue:`43885`)
 - :meth:`DataFrame.compare` now accepts an argument ``result_names`` to allow the user to specify the result's names of both left and right DataFrame which are being compared. This is by default ``'self'`` and ``'other'`` (:issue:`44354`)
-- Added ``copy`` keyword to :meth:`Series.set_axis` and :meth:`DataFrame.set_axis` to allow user to set axis on a new object without necessarily copying the underlying data (:issue:`??`)
+- Added ``copy`` keyword to :meth:`Series.set_axis` and :meth:`DataFrame.set_axis` to allow user to set axis on a new object without necessarily copying the underlying data (:issue:`47932`)
 
 .. ---------------------------------------------------------------------------
 .. _whatsnew_150.notable_bug_fixes:
diff --git a/pandas/tests/frame/methods/test_set_axis.py b/pandas/tests/frame/methods/test_set_axis.py
index 2bf612895aa1e..556a5ab13ce5b 100644
--- a/pandas/tests/frame/methods/test_set_axis.py
+++ b/pandas/tests/frame/methods/test_set_axis.py
@@ -25,7 +25,7 @@ def test_set_axis(self, obj):
         tm.assert_equal(expected, result)
 
     def test_set_axis_copy(self, obj):
-        # Test copy keyword
+        # Test copy keyword GH#47932
         new_index = list("abcd")[: len(obj)]
 
         expected = obj.copy()

From 526b471f1b0918ff75729eed39c539c5e77a5570 Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Tue, 2 Aug 2022 12:18:01 -0700
Subject: [PATCH 3/9] fix test

---
 pandas/core/generic.py                      |  1 +
 pandas/tests/frame/methods/test_set_axis.py | 24 ++++++++++++++++++---
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index d8393ea9f435c..38432afbc77fe 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -744,6 +744,7 @@ def set_axis(
         labels,
         axis: Axis = 0,
         inplace: bool_t = False,
+        *,
         copy: bool_t | lib.NoDefault = lib.no_default,
     ) -> NDFrameT | None:
         """
diff --git a/pandas/tests/frame/methods/test_set_axis.py b/pandas/tests/frame/methods/test_set_axis.py
index 556a5ab13ce5b..a43f118a19265 100644
--- a/pandas/tests/frame/methods/test_set_axis.py
+++ b/pandas/tests/frame/methods/test_set_axis.py
@@ -40,20 +40,38 @@ def test_set_axis_copy(self, obj):
         tm.assert_equal(expected, result)
         assert result is not obj
         # check we DID make a copy
-        assert not tm.shares_memory(result, obj)
+        if obj.ndim == 1:
+            assert not tm.shares_memory(result, obj)
+        else:
+            assert not any(
+                tm.shares_memory(result.iloc[:, i], obj.iloc[:, i])
+                for i in range(obj.shape[1])
+            )
 
         result = obj.set_axis(new_index, axis=0, copy=False)
         tm.assert_equal(expected, result)
         assert result is not obj
         # check we did NOT make a copy
-        assert tm.shares_memory(result, obj)
+        if obj.ndim == 1:
+            assert not tm.shares_memory(result, obj)
+        else:
+            assert not any(
+                tm.shares_memory(result.iloc[:, i], obj.iloc[:, i])
+                for i in range(obj.shape[1])
+            )
 
         # copy defaults to True
         result = obj.set_axis(new_index, axis=0)
         tm.assert_equal(expected, result)
         assert result is not obj
         # check we DID make a copy
-        assert not tm.shares_memory(result, obj)
+        if obj.ndim == 1:
+            assert not tm.shares_memory(result, obj)
+        else:
+            assert not any(
+                tm.shares_memory(result.iloc[:, i], obj.iloc[:, i])
+                for i in range(obj.shape[1])
+            )
 
     @pytest.mark.parametrize("axis", [0, "index", 1, "columns"])
     def test_set_axis_inplace_axis(self, axis, obj):

From 86173b5caa3c1be44793d475dd98581921f24db4 Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Wed, 3 Aug 2022 18:21:32 -0700
Subject: [PATCH 4/9] fix test

---
 pandas/tests/frame/methods/test_set_axis.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/frame/methods/test_set_axis.py b/pandas/tests/frame/methods/test_set_axis.py
index a43f118a19265..6639a6804ec64 100644
--- a/pandas/tests/frame/methods/test_set_axis.py
+++ b/pandas/tests/frame/methods/test_set_axis.py
@@ -53,9 +53,9 @@ def test_set_axis_copy(self, obj):
         assert result is not obj
         # check we did NOT make a copy
         if obj.ndim == 1:
-            assert not tm.shares_memory(result, obj)
+            assert tm.shares_memory(result, obj)
         else:
-            assert not any(
+            assert all(
                 tm.shares_memory(result.iloc[:, i], obj.iloc[:, i])
                 for i in range(obj.shape[1])
             )

From 360f0b7945bbfcb1cf22f8d1f8455d325dbc5e59 Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Wed, 3 Aug 2022 18:27:27 -0700
Subject: [PATCH 5/9] troubleshoot mypy

---
 pandas/core/frame.py   | 1 +
 pandas/core/generic.py | 1 +
 2 files changed, 2 insertions(+)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 2784da605e339..2265fcb263bb3 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -5086,6 +5086,7 @@ def set_axis(
         labels,
         axis: Axis = 0,
         inplace: bool = False,
+        *,
         copy: bool | lib.NoDefault = lib.no_default,
     ):
         return super().set_axis(labels, axis=axis, inplace=inplace, copy=copy)
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 38432afbc77fe..0a8a9108c8604 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -735,6 +735,7 @@ def set_axis(
         *,
         axis: Axis = ...,
         inplace: bool_t | lib.NoDefault = ...,
+        copy: bool_t | lib.NoDefault = ...,
     ) -> NDFrameT | None:
         ...
 

From a9610340b253481f821f513b2e798ce020e81368 Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Thu, 4 Aug 2022 09:46:18 -0700
Subject: [PATCH 6/9] mypy fixup

---
 pandas/core/generic.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 0a8a9108c8604..e80b4a45bb774 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -734,7 +734,7 @@ def set_axis(
         labels,
         *,
         axis: Axis = ...,
-        inplace: bool_t | lib.NoDefault = ...,
+        inplace: bool_t = ...,
         copy: bool_t | lib.NoDefault = ...,
     ) -> NDFrameT | None:
         ...

From 135527b615768ec9840884a336b3c951c8b3cd70 Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Tue, 9 Aug 2022 15:39:35 -0700
Subject: [PATCH 7/9] test inplace=True/copy=False case

---
 pandas/tests/frame/methods/test_set_axis.py | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/pandas/tests/frame/methods/test_set_axis.py b/pandas/tests/frame/methods/test_set_axis.py
index 6639a6804ec64..67488dff3c335 100644
--- a/pandas/tests/frame/methods/test_set_axis.py
+++ b/pandas/tests/frame/methods/test_set_axis.py
@@ -28,6 +28,7 @@ def test_set_axis_copy(self, obj):
         # Test copy keyword GH#47932
         new_index = list("abcd")[: len(obj)]
 
+        orig = obj.iloc[:]
         expected = obj.copy()
         expected.index = new_index
 
@@ -73,6 +74,19 @@ def test_set_axis_copy(self, obj):
                 for i in range(obj.shape[1])
             )
 
+        # Do this last since it alters obj inplace
+        res = obj.set_axis(new_index, inplace=True, copy=False)
+        assert res is None
+        tm.assert_equal(expected, obj)
+        # check we did NOT make a copy
+        if obj.ndim == 1:
+            assert tm.shares_memory(obj, orig)
+        else:
+            assert all(
+                tm.shares_memory(obj.iloc[:, i], orig.iloc[:, i])
+                for i in range(obj.shape[1])
+            )
+
     @pytest.mark.parametrize("axis", [0, "index", 1, "columns"])
     def test_set_axis_inplace_axis(self, axis, obj):
         # GH#14636

From 25b98820b4cb2de547e559e4770c1acb66631c6a Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Wed, 17 Aug 2022 12:51:47 -0700
Subject: [PATCH 8/9] DEPR: inplace keyword in set_axis

---
 doc/source/whatsnew/v1.5.0.rst                |  1 +
 pandas/core/frame.py                          | 11 +++---
 pandas/core/generic.py                        | 37 +++++++++++++------
 pandas/core/groupby/groupby.py                |  9 +++--
 pandas/core/series.py                         |  6 +--
 pandas/tests/frame/methods/test_set_axis.py   | 17 ++++++---
 pandas/tests/generic/test_duplicate_labels.py | 12 +++++-
 7 files changed, 62 insertions(+), 31 deletions(-)

diff --git a/doc/source/whatsnew/v1.5.0.rst b/doc/source/whatsnew/v1.5.0.rst
index 0ceac8aeb9db8..a51094ccfabf2 100644
--- a/doc/source/whatsnew/v1.5.0.rst
+++ b/doc/source/whatsnew/v1.5.0.rst
@@ -847,6 +847,7 @@ Other Deprecations
 - Deprecated the ``inplace`` keyword in :meth:`Categorical.set_ordered`, :meth:`Categorical.as_ordered`, and :meth:`Categorical.as_unordered` (:issue:`37643`)
 - Deprecated setting a categorical's categories with ``cat.categories = ['a', 'b', 'c']``, use :meth:`Categorical.rename_categories` instead (:issue:`37643`)
 - Deprecated unused arguments ``encoding`` and ``verbose`` in :meth:`Series.to_excel` and :meth:`DataFrame.to_excel` (:issue:`47912`)
+- Deprecated the ``inplace`` keyword in :meth:`DataFrame.set_axis` and :meth:`Series.set_axis`, use ``obj = obj.set_axis(..., copy=False)`` instead (:issue:`??`)
 - Deprecated producing a single element when iterating over a :class:`DataFrameGroupBy` or a :class:`SeriesGroupBy` that has been grouped by a list of length 1; A tuple of length one will be returned instead (:issue:`42795`)
 - Fixed up warning message of deprecation of :meth:`MultiIndex.lesort_depth` as public method, as the message previously referred to :meth:`MultiIndex.is_lexsorted` instead (:issue:`38701`)
 - Deprecated the ``sort_columns`` argument in :meth:`DataFrame.plot` and :meth:`Series.plot` (:issue:`47563`).
diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 7a4f41da5840c..93096126d0682 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -5060,7 +5060,7 @@ def set_axis(
         labels,
         *,
         axis: Axis = ...,
-        inplace: Literal[False] = ...,
+        inplace: Literal[False] | lib.NoDefault = ...,
         copy: bool | lib.NoDefault = ...,
     ) -> DataFrame:
         ...
@@ -5082,7 +5082,7 @@ def set_axis(
         labels,
         *,
         axis: Axis = ...,
-        inplace: bool = ...,
+        inplace: bool | lib.NoDefault = ...,
         copy: bool | lib.NoDefault = ...,
     ) -> DataFrame | None:
         ...
@@ -5111,10 +5111,9 @@ def set_axis(
         1  2   5
         2  3   6
 
-        Now, update the labels inplace.
+        Now, update the labels without copying the underlying data.
 
-        >>> df.set_axis(['i', 'ii'], axis='columns', inplace=True)
-        >>> df
+        >>> df.set_axis(['i', 'ii'], axis='columns', copy=False)
            i  ii
         0  1   4
         1  2   5
@@ -5132,7 +5131,7 @@ def set_axis(
         self,
         labels,
         axis: Axis = 0,
-        inplace: bool = False,
+        inplace: bool | lib.NoDefault = lib.no_default,
         *,
         copy: bool | lib.NoDefault = lib.no_default,
     ):
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 45b839f175a88..1cf308f06c7c7 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -715,7 +715,7 @@ def set_axis(
         labels,
         *,
         axis: Axis = ...,
-        inplace: Literal[False] = ...,
+        inplace: Literal[False] | lib.NoDefault = ...,
         copy: bool_t | lib.NoDefault = ...,
     ) -> NDFrameT:
         ...
@@ -737,7 +737,7 @@ def set_axis(
         labels,
         *,
         axis: Axis = ...,
-        inplace: bool_t = ...,
+        inplace: bool_t | lib.NoDefault = ...,
         copy: bool_t | lib.NoDefault = ...,
     ) -> NDFrameT | None:
         ...
@@ -747,7 +747,7 @@ def set_axis(
         self: NDFrameT,
         labels,
         axis: Axis = 0,
-        inplace: bool_t = False,
+        inplace: bool_t | lib.NoDefault = lib.no_default,
         *,
         copy: bool_t | lib.NoDefault = lib.no_default,
     ) -> NDFrameT | None:
@@ -769,6 +769,8 @@ def set_axis(
         inplace : bool, default False
             Whether to return a new %(klass)s instance.
 
+            .. deprecated:: 1.5.0
+
         copy : bool, default True
             Whether to make a copy of the underlying data.
 
@@ -783,6 +785,17 @@ def set_axis(
         --------
         %(klass)s.rename_axis : Alter the name of the index%(see_also_sub)s.
         """
+        if inplace is not lib.no_default:
+            warnings.warn(
+                f"{type(self).__name__}.set_axis 'inplace' keyword is deprecated "
+                "and will be removed in a future version. Use "
+                "`obj = obj.set_axis(..., copy=False)` instead",
+                FutureWarning,
+                stacklevel=find_stack_level(inspect.currentframe()),
+            )
+        else:
+            inplace = False
+
         if inplace:
             if copy is True:
                 raise ValueError("Cannot specify both inplace=True and copy=True")
@@ -795,14 +808,13 @@ def set_axis(
 
     @final
     def _set_axis_nocheck(self, labels, axis: Axis, inplace: bool_t, copy: bool_t):
-        # NDFrame.rename with inplace=False calls set_axis(inplace=True) on a copy.
         if inplace:
             setattr(self, self._get_axis_name(axis), labels)
         else:
             # With copy=False, we create a new object but don't copy the
             #  underlying data.
             obj = self.copy(deep=copy)
-            obj.set_axis(labels, axis=axis, inplace=True)
+            setattr(obj, obj._get_axis_name(axis), labels)
             return obj
 
     def _set_axis(self, axis: int, labels: AnyArrayLike | list) -> None:
@@ -904,7 +916,7 @@ def droplevel(self: NDFrameT, level: IndexLabel, axis: Axis = 0) -> NDFrameT:
         """
         labels = self._get_axis(axis)
         new_labels = labels.droplevel(level)
-        return self.set_axis(new_labels, axis=axis, inplace=False)
+        return self.set_axis(new_labels, axis=axis)
 
     def pop(self, item: Hashable) -> Series | Any:
         result = self[item]
@@ -1363,7 +1375,11 @@ def _set_axis_name(self, name, axis=0, inplace=False):
 
         inplace = validate_bool_kwarg(inplace, "inplace")
         renamed = self if inplace else self.copy()
-        renamed.set_axis(idx, axis=axis, inplace=True)
+        if axis == 0:
+            renamed.index = idx
+        else:
+            renamed.columns = idx
+
         if not inplace:
             return renamed
 
@@ -10205,8 +10221,7 @@ def slice_shift(self: NDFrameT, periods: int = 1, axis=0) -> NDFrameT:
 
         new_obj = self._slice(vslicer, axis=axis)
         shifted_axis = self._get_axis(axis)[islicer]
-        new_obj.set_axis(shifted_axis, axis=axis, inplace=True)
-
+        new_obj = new_obj.set_axis(shifted_axis, axis=axis, copy=False)
         return new_obj.__finalize__(self, method="slice_shift")
 
     @final
@@ -10465,7 +10480,7 @@ def _tz_convert(ax, tz):
             ax = _tz_convert(ax, tz)
 
         result = self.copy(deep=copy)
-        result = result.set_axis(ax, axis=axis, inplace=False)
+        result = result.set_axis(ax, axis=axis, copy=False)
         return result.__finalize__(self, method="tz_convert")
 
     @final
@@ -10635,7 +10650,7 @@ def _tz_localize(ax, tz, ambiguous, nonexistent):
             ax = _tz_localize(ax, tz, ambiguous, nonexistent)
 
         result = self.copy(deep=copy)
-        result = result.set_axis(ax, axis=axis, inplace=False)
+        result = result.set_axis(ax, axis=axis, copy=False)
         return result.__finalize__(self, method="tz_localize")
 
     # ----------------------------------------------------------------------
diff --git a/pandas/core/groupby/groupby.py b/pandas/core/groupby/groupby.py
index 9523857925f8f..43316873a2ea7 100644
--- a/pandas/core/groupby/groupby.py
+++ b/pandas/core/groupby/groupby.py
@@ -1200,21 +1200,22 @@ def _set_result_index_ordered(
         # set the result index on the passed values object and
         # return the new object, xref 8046
 
+        obj_axis = self.obj._get_axis(self.axis)
+
         if self.grouper.is_monotonic and not self.grouper.has_dropped_na:
             # shortcut if we have an already ordered grouper
-            result.set_axis(self.obj._get_axis(self.axis), axis=self.axis, inplace=True)
+            result = result.set_axis(obj_axis, axis=self.axis, copy=False)
             return result
 
         # row order is scrambled => sort the rows by position in original index
         original_positions = Index(self.grouper.result_ilocs())
-        result.set_axis(original_positions, axis=self.axis, inplace=True)
+        result = result.set_axis(original_positions, axis=self.axis, copy=False)
         result = result.sort_index(axis=self.axis)
-        obj_axis = self.obj._get_axis(self.axis)
         if self.grouper.has_dropped_na:
             # Add back in any missing rows due to dropna - index here is integral
             # with values referring to the row of the input so can use RangeIndex
             result = result.reindex(RangeIndex(len(obj_axis)), axis=self.axis)
-        result.set_axis(obj_axis, axis=self.axis, inplace=True)
+        result = result.set_axis(obj_axis, axis=self.axis, copy=False)
 
         return result
 
diff --git a/pandas/core/series.py b/pandas/core/series.py
index f55d6a26255a0..13aa12287072c 100644
--- a/pandas/core/series.py
+++ b/pandas/core/series.py
@@ -4980,7 +4980,7 @@ def set_axis(
         labels,
         *,
         axis: Axis = ...,
-        inplace: Literal[False] = ...,
+        inplace: Literal[False] | lib.NoDefault = ...,
         copy: bool | lib.NoDefault = ...,
     ) -> Series:
         ...
@@ -5002,7 +5002,7 @@ def set_axis(
         labels,
         *,
         axis: Axis = ...,
-        inplace: bool = ...,
+        inplace: bool | lib.NoDefault = ...,
         copy: bool | lib.NoDefault = ...,
     ) -> Series | None:
         ...
@@ -5038,7 +5038,7 @@ def set_axis(  # type: ignore[override]
         self,
         labels,
         axis: Axis = 0,
-        inplace: bool = False,
+        inplace: bool | lib.NoDefault = lib.no_default,
         copy: bool | lib.NoDefault = lib.no_default,
     ) -> Series | None:
         return super().set_axis(labels, axis=axis, inplace=inplace, copy=copy)
diff --git a/pandas/tests/frame/methods/test_set_axis.py b/pandas/tests/frame/methods/test_set_axis.py
index 67488dff3c335..f105a38e6fdd0 100644
--- a/pandas/tests/frame/methods/test_set_axis.py
+++ b/pandas/tests/frame/methods/test_set_axis.py
@@ -21,7 +21,9 @@ def test_set_axis(self, obj):
         expected.index = new_index
 
         # inplace=False
-        result = obj.set_axis(new_index, axis=0, inplace=False)
+        msg = "set_axis 'inplace' keyword is deprecated"
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            result = obj.set_axis(new_index, axis=0, inplace=False)
         tm.assert_equal(expected, result)
 
     def test_set_axis_copy(self, obj):
@@ -35,7 +37,8 @@ def test_set_axis_copy(self, obj):
         with pytest.raises(
             ValueError, match="Cannot specify both inplace=True and copy=True"
         ):
-            obj.set_axis(new_index, axis=0, inplace=True, copy=True)
+            with tm.assert_produces_warning(FutureWarning):
+                obj.set_axis(new_index, axis=0, inplace=True, copy=True)
 
         result = obj.set_axis(new_index, axis=0, copy=True)
         tm.assert_equal(expected, result)
@@ -75,7 +78,8 @@ def test_set_axis_copy(self, obj):
             )
 
         # Do this last since it alters obj inplace
-        res = obj.set_axis(new_index, inplace=True, copy=False)
+        with tm.assert_produces_warning(FutureWarning):
+            res = obj.set_axis(new_index, inplace=True, copy=False)
         assert res is None
         tm.assert_equal(expected, obj)
         # check we did NOT make a copy
@@ -103,7 +107,8 @@ def test_set_axis_inplace_axis(self, axis, obj):
             expected.columns = new_index
 
         result = obj.copy()
-        result.set_axis(new_index, axis=axis, inplace=True)
+        with tm.assert_produces_warning(FutureWarning):
+            result.set_axis(new_index, axis=axis, inplace=True)
         tm.assert_equal(result, expected)
 
     def test_set_axis_unnamed_kwarg_warns(self, obj):
@@ -113,7 +118,9 @@ def test_set_axis_unnamed_kwarg_warns(self, obj):
         expected = obj.copy()
         expected.index = new_index
 
-        with tm.assert_produces_warning(None):
+        with tm.assert_produces_warning(
+            FutureWarning, match="set_axis 'inplace' keyword"
+        ):
             result = obj.set_axis(new_index, inplace=False)
         tm.assert_equal(result, expected)
 
diff --git a/pandas/tests/generic/test_duplicate_labels.py b/pandas/tests/generic/test_duplicate_labels.py
index c83c8e1d568e6..0546534d91399 100644
--- a/pandas/tests/generic/test_duplicate_labels.py
+++ b/pandas/tests/generic/test_duplicate_labels.py
@@ -429,11 +429,19 @@ def test_inplace_raises(method, frame_only):
     s.flags.allows_duplicate_labels = False
     msg = "Cannot specify"
 
+    warn_msg = "Series.set_axis 'inplace' keyword"
+    if "set_axis" in str(method):
+        warn = FutureWarning
+    else:
+        warn = None
+
     with pytest.raises(ValueError, match=msg):
-        method(df)
+        with tm.assert_produces_warning(warn, match=warn_msg):
+            method(df)
     if not frame_only:
         with pytest.raises(ValueError, match=msg):
-            method(s)
+            with tm.assert_produces_warning(warn, match=warn_msg):
+                method(s)
 
 
 def test_pickle():

From 0fef4a17be7f169dac682a05950057f9689d98e1 Mon Sep 17 00:00:00 2001
From: Brock <jbrockmendel@gmail.com>
Date: Wed, 17 Aug 2022 12:54:56 -0700
Subject: [PATCH 9/9] GH ref

---
 doc/source/whatsnew/v1.5.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.5.0.rst b/doc/source/whatsnew/v1.5.0.rst
index a51094ccfabf2..c95660bf86114 100644
--- a/doc/source/whatsnew/v1.5.0.rst
+++ b/doc/source/whatsnew/v1.5.0.rst
@@ -847,7 +847,7 @@ Other Deprecations
 - Deprecated the ``inplace`` keyword in :meth:`Categorical.set_ordered`, :meth:`Categorical.as_ordered`, and :meth:`Categorical.as_unordered` (:issue:`37643`)
 - Deprecated setting a categorical's categories with ``cat.categories = ['a', 'b', 'c']``, use :meth:`Categorical.rename_categories` instead (:issue:`37643`)
 - Deprecated unused arguments ``encoding`` and ``verbose`` in :meth:`Series.to_excel` and :meth:`DataFrame.to_excel` (:issue:`47912`)
-- Deprecated the ``inplace`` keyword in :meth:`DataFrame.set_axis` and :meth:`Series.set_axis`, use ``obj = obj.set_axis(..., copy=False)`` instead (:issue:`??`)
+- Deprecated the ``inplace`` keyword in :meth:`DataFrame.set_axis` and :meth:`Series.set_axis`, use ``obj = obj.set_axis(..., copy=False)`` instead (:issue:`48130`)
 - Deprecated producing a single element when iterating over a :class:`DataFrameGroupBy` or a :class:`SeriesGroupBy` that has been grouped by a list of length 1; A tuple of length one will be returned instead (:issue:`42795`)
 - Fixed up warning message of deprecation of :meth:`MultiIndex.lesort_depth` as public method, as the message previously referred to :meth:`MultiIndex.is_lexsorted` instead (:issue:`38701`)
 - Deprecated the ``sort_columns`` argument in :meth:`DataFrame.plot` and :meth:`Series.plot` (:issue:`47563`).