Revert #47934 (#48201)

Author: jbrockmendel

doc/source/whatsnew/v1.5.0.rst

@@ -331,7 +331,6 @@ Other enhancements
 - :meth:`DataFrame.quantile` gained a ``method`` argument that can accept ``table`` to evaluate multi-column quantiles (:issue:`43881`)
 - :class:`Interval` now supports checking whether one interval is contained by another interval (:issue:`46613`)
 - 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`)
-- :meth:`Series.add_suffix`, :meth:`DataFrame.add_suffix`, :meth:`Series.add_prefix` and :meth:`DataFrame.add_prefix` support a ``copy`` argument. If ``False``, the underlying data is not copied in the returned object (:issue:`47934`)
 - :meth:`DataFrame.set_index` now supports a ``copy`` keyword. If ``False``, the underlying data is not copied when a new :class:`DataFrame` is returned (:issue:`48043`)
 - The method :meth:`.ExtensionArray.factorize` accepts ``use_na_sentinel=False`` for determining how null values are to be treated (:issue:`46601`)
 

pandas/core/generic.py

@@ -4619,7 +4619,7 @@ def _update_inplace(self, result, verify_is_copy: bool_t = True) -> None:
         self._maybe_update_cacher(verify_is_copy=verify_is_copy, inplace=True)
 
     @final
-    def add_prefix(self: NDFrameT, prefix: str, copy: bool_t = True) -> NDFrameT:
+    def add_prefix(self: NDFrameT, prefix: str) -> NDFrameT:
         """
         Prefix labels with string `prefix`.
 
@@ -4630,10 +4630,6 @@ def add_prefix(self: NDFrameT, prefix: str, copy: bool_t = True) -> NDFrameT:
         ----------
         prefix : str
             The string to add before each label.
-        copy : bool, default True
-            Whether to copy the underlying data.
-
-             .. versionadded:: 1.5.0
 
         Returns
         -------
@@ -4684,10 +4680,10 @@ def add_prefix(self: NDFrameT, prefix: str, copy: bool_t = True) -> NDFrameT:
         # expected "NDFrameT")
         # error: Argument 1 to "rename" of "NDFrame" has incompatible type
         # "**Dict[str, partial[str]]"; expected "Union[str, int, None]"
-        return self._rename(**mapper, copy=copy)  # type: ignore[return-value, arg-type]
+        return self._rename(**mapper)  # type: ignore[return-value, arg-type]
 
     @final
-    def add_suffix(self: NDFrameT, suffix: str, copy: bool_t = True) -> NDFrameT:
+    def add_suffix(self: NDFrameT, suffix: str) -> NDFrameT:
         """
         Suffix labels with string `suffix`.
 
@@ -4698,10 +4694,6 @@ def add_suffix(self: NDFrameT, suffix: str, copy: bool_t = True) -> NDFrameT:
         ----------
         suffix : str
             The string to add after each label.
-        copy : bool, default True
-            Whether to copy the underlying data.
-
-             .. versionadded:: 1.5.0
 
         Returns
         -------
@@ -4752,7 +4744,7 @@ def add_suffix(self: NDFrameT, suffix: str, copy: bool_t = True) -> NDFrameT:
         # expected "NDFrameT")
         # error: Argument 1 to "rename" of "NDFrame" has incompatible type
         # "**Dict[str, partial[str]]"; expected "Union[str, int, None]"
-        return self._rename(**mapper, copy=copy)  # type: ignore[return-value, arg-type]
+        return self._rename(**mapper)  # type: ignore[return-value, arg-type]
 
     @overload
     def sort_values(

pandas/tests/frame/methods/test_add_prefix_suffix.py

@@ -18,56 +18,3 @@ def test_add_prefix_suffix(float_frame):
     with_pct_suffix = float_frame.add_suffix("%")
     expected = Index([f"{c}%" for c in float_frame.columns])
     tm.assert_index_equal(with_pct_suffix.columns, expected)
-
-
-def test_add_prefix_suffix_copy(float_frame):
-    # GH#47934
-    ser = float_frame.iloc[0]
-
-    with_prefix = float_frame.add_prefix("foo#", copy=True)
-    expected = Index([f"foo#{c}" for c in float_frame.columns])
-    tm.assert_index_equal(with_prefix.columns, expected)
-    assert not any(
-        tm.shares_memory(float_frame.iloc[:, i], with_prefix.iloc[:, i])
-        for i in range(float_frame.shape[1])
-    )
-
-    ser_with_prefix = ser.add_prefix("foo#", copy=True)
-    tm.assert_index_equal(ser_with_prefix.index, expected)
-    assert not tm.shares_memory(ser_with_prefix, ser)
-
-    with_prefix = float_frame.add_prefix("foo#", copy=False)
-    expected = Index([f"foo#{c}" for c in float_frame.columns])
-    tm.assert_index_equal(with_prefix.columns, expected)
-    assert all(
-        tm.shares_memory(float_frame.iloc[:, i], with_prefix.iloc[:, i])
-        for i in range(float_frame.shape[1])
-    )
-
-    ser_with_prefix = ser.add_prefix("foo#", copy=False)
-    tm.assert_index_equal(ser_with_prefix.index, expected)
-    assert tm.shares_memory(ser_with_prefix, ser)
-
-    with_suffix = float_frame.add_suffix("#foo", copy=True)
-    expected = Index([f"{c}#foo" for c in float_frame.columns])
-    tm.assert_index_equal(with_suffix.columns, expected)
-    assert not any(
-        tm.shares_memory(float_frame.iloc[:, i], with_suffix.iloc[:, i])
-        for i in range(float_frame.shape[1])
-    )
-
-    ser_with_suffix = ser.add_suffix("#foo", copy=True)
-    tm.assert_index_equal(ser_with_suffix.index, expected)
-    assert not tm.shares_memory(ser_with_suffix, ser)
-
-    with_suffix = float_frame.add_suffix("#foo", copy=False)
-    expected = Index([f"{c}#foo" for c in float_frame.columns])
-    tm.assert_index_equal(with_suffix.columns, expected)
-    assert all(
-        tm.shares_memory(float_frame.iloc[:, i], with_suffix.iloc[:, i])
-        for i in range(float_frame.shape[1])
-    )
-
-    ser_with_suffix = ser.add_suffix("#foo", copy=False)
-    tm.assert_index_equal(ser_with_suffix.index, expected)
-    assert tm.shares_memory(ser_with_suffix, ser)