ENH: Deprecate non-keyword arguments for Index.set_names.

pandas/core/indexes/base.py

@@ -1528,7 +1528,6 @@ def _set_names(self, values, level=None) -> None:
     names = property(fset=_set_names, fget=_get_names)
 
     @deprecate_nonkeyword_arguments(version=None, allowed_args=["self", "names"])
-    @final
     def set_names(self, names, level=None, inplace: bool = False):
         """
         Set Index or MultiIndex name.

pandas/core/indexes/multi.py

@@ -41,6 +41,7 @@
 from pandas.util._decorators import (
     Appender,
     cache_readonly,
+    deprecate_nonkeyword_arguments,
     doc,
 )
 
@@ -295,7 +296,6 @@ class MultiIndex(Index):
     _levels = FrozenList()
     _codes = FrozenList()
     _comparables = ["names"]
-    rename = Index.set_names
 
     sortorder: int | None
 
@@ -3780,19 +3780,24 @@ def delete(self, loc) -> MultiIndex:
             verify_integrity=False,
         )
 
-    @doc(Index.isin)
+    # @doc(Index.isin)
     def isin(self, values, level=None) -> np.ndarray:
         if level is None:
             values = MultiIndex.from_tuples(values, names=self.names)._values
             return algos.isin(self._values, values)
         else:
             num = self._get_level_number(level)
             levs = self.get_level_values(num)
-
             if levs.size == 0:
                 return np.zeros(len(levs), dtype=np.bool_)
             return levs.isin(values)
 
+    @deprecate_nonkeyword_arguments(version=None, allowed_args=["self", "names"])
+    def set_names(self, names, level=None, inplace: bool = False) -> MultiIndex | None:
+        return super().set_names(names=names, level=level, inplace=inplace)
+
+    rename = set_names
+
     # ---------------------------------------------------------------
     # Arithmetic/Numeric Methods - Disabled
 

pandas/tests/indexes/multi/test_get_set.py

@@ -348,21 +348,17 @@ def test_set_names_with_nlevel_1(inplace):
 def test_multi_set_names_pos_args_deprecation():
     # GH#41485
     idx = MultiIndex.from_product([["python", "cobra"], [2018, 2019]])
-
     msg = (
-        "In a future version of pandas all arguments of Index.set_names "
+        "In a future version of pandas all arguments of MultiIndex.set_names "
         "except for the argument 'names' will be keyword-only"
     )
-
     with tm.assert_produces_warning(FutureWarning, match=msg):
         result = idx.set_names(["kind", "year"], None)
-
     expected = MultiIndex(
         levels=[["python", "cobra"], [2018, 2019]],
         codes=[[0, 0, 1, 1], [0, 1, 0, 1]],
         names=["kind", "year"],
     )
-
     tm.assert_index_equal(result, expected)