DEPR fixup warning message of MultiIndex.lexsort_depth deprecation (pandas-dev#48025)

fixup warning message of MultiIndex.lexsort_depth deprecation

Author: MarcoGorelli

doc/source/whatsnew/v1.5.0.rst

@@ -843,6 +843,7 @@ Other Deprecations
 - 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 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`)
 
 .. ---------------------------------------------------------------------------
 .. _whatsnew_150.performance:

pandas/core/indexes/multi.py

@@ -1911,7 +1911,7 @@ def _is_lexsorted(self) -> bool:
     @property
     def lexsort_depth(self) -> int:
         warnings.warn(
-            "MultiIndex.is_lexsorted is deprecated as a public function, "
+            "MultiIndex.lexsort_depth is deprecated as a public function, "
             "users should use MultiIndex.is_monotonic_increasing instead.",
             FutureWarning,
             stacklevel=find_stack_level(inspect.currentframe()),

pandas/tests/indexes/multi/test_lexsort.py

@@ -24,7 +24,10 @@ def test_is_lexsorted(self):
 
     def test_is_lexsorted_deprecation(self):
         # GH 32259
-        with tm.assert_produces_warning():
+        with tm.assert_produces_warning(
+            FutureWarning,
+            match="MultiIndex.is_lexsorted is deprecated as a public function",
+        ):
             MultiIndex.from_arrays([["a", "b", "c"], ["d", "f", "e"]]).is_lexsorted()
 
 
@@ -53,5 +56,8 @@ def test_lexsort_depth(self):
 
     def test_lexsort_depth_deprecation(self):
         # GH 32259
-        with tm.assert_produces_warning():
+        with tm.assert_produces_warning(
+            FutureWarning,
+            match="MultiIndex.lexsort_depth is deprecated as a public function",
+        ):
             MultiIndex.from_arrays([["a", "b", "c"], ["d", "f", "e"]]).lexsort_depth