DEPR: Index.is_mixed (pandas-dev#33291)

Author: jbrockmendel

doc/source/whatsnew/v1.1.0.rst

@@ -256,6 +256,7 @@ Deprecations
 - :meth:`DataFrame.to_dict` has deprecated accepting short names for ``orient`` in future versions (:issue:`32515`)
 - :meth:`Categorical.to_dense` is deprecated and will be removed in a future version, use ``np.asarray(cat)`` instead (:issue:`32639`)
 - The ``fastpath`` keyword in the ``SingleBlockManager`` constructor is deprecated and will be removed in a future version (:issue:`33092`)
+- :meth:`Index.is_mixed` is deprecated and will be removed in a future version, check ``index.inferred_type`` directly instead (:issue:`32922`)
 
 .. ---------------------------------------------------------------------------
 

pandas/core/indexes/base.py

@@ -1955,6 +1955,12 @@ def is_mixed(self) -> bool:
         >>> idx.is_mixed()
         False
         """
+        warnings.warn(
+            "Index.is_mixed is deprecated and will be removed in a future version. "
+            "Check index.inferred_type directly instead.",
+            FutureWarning,
+            stacklevel=2,
+        )
         return self.inferred_type in ["mixed"]
 
     def holds_integer(self) -> bool:
@@ -3131,7 +3137,7 @@ def is_int(v):
         # convert the slice to an indexer here
 
         # if we are mixed and have integers
-        if is_positional and self.is_mixed():
+        if is_positional:
             try:
                 # Validate start & stop
                 if start is not None:

pandas/tests/indexes/test_base.py

@@ -1160,6 +1160,12 @@ def test_intersection_difference(self, indices, sort):
         diff = indices.difference(indices, sort=sort)
         tm.assert_index_equal(inter, diff)
 
+    def test_is_mixed_deprecated(self):
+        # GH#32922
+        index = self.create_index()
+        with tm.assert_produces_warning(FutureWarning):
+            index.is_mixed()
+
     @pytest.mark.parametrize(
         "indices, expected",
         [