DEPR: Index.__and__, __or__, __xor__ (pandas-dev#49503)

* DEPR: Index.__and__, __or__, __xor__

* construct expected explicitly

doc/source/whatsnew/v2.0.0.rst

@@ -429,6 +429,7 @@ Removal of prior version deprecations/changes
 - Changed behavior of :meth:`Index.to_frame` with explicit ``name=None`` to use ``None`` for the column name instead of the index's name or default ``0`` (:issue:`45523`)
 - Changed behavior of :class:`DataFrame` constructor given floating-point ``data`` and an integer ``dtype``, when the data cannot be cast losslessly, the floating point dtype is retained, matching :class:`Series` behavior (:issue:`41170`)
 - Changed behavior of :class:`Index` constructor when given a ``np.ndarray`` with object-dtype containing numeric entries; this now retains object dtype rather than inferring a numeric dtype, consistent with :class:`Series` behavior (:issue:`42870`)
+- Changed behavior of :meth:`Index.__and__`, :meth:`Index.__or__` and :meth:`Index.__xor__` to behave as logical operations (matching :class:`Series` behavior) instead of aliases for set operations (:issue:`37374`)
 - Changed behavior of :class:`DataFrame` constructor when passed a ``dtype`` (other than int) that the data cannot be cast to; it now raises instead of silently ignoring the dtype (:issue:`41733`)
 - Changed the behavior of :class:`Series` constructor, it will no longer infer a datetime64 or timedelta64 dtype from string entries (:issue:`41731`)
 - Changed behavior of :class:`Timestamp` constructor with a ``np.datetime64`` object and a ``tz`` passed to interpret the input as a wall-time as opposed to a UTC time (:issue:`42288`)

pandas/core/indexes/base.py

@@ -2932,39 +2932,6 @@ def __iadd__(self, other):
         # alias for __add__
         return self + other
 
-    @final
-    def __and__(self, other):
-        warnings.warn(
-            "Index.__and__ operating as a set operation is deprecated, "
-            "in the future this will be a logical operation matching "
-            "Series.__and__.  Use index.intersection(other) instead.",
-            FutureWarning,
-            stacklevel=find_stack_level(),
-        )
-        return self.intersection(other)
-
-    @final
-    def __or__(self, other):
-        warnings.warn(
-            "Index.__or__ operating as a set operation is deprecated, "
-            "in the future this will be a logical operation matching "
-            "Series.__or__.  Use index.union(other) instead.",
-            FutureWarning,
-            stacklevel=find_stack_level(),
-        )
-        return self.union(other)
-
-    @final
-    def __xor__(self, other):
-        warnings.warn(
-            "Index.__xor__ operating as a set operation is deprecated, "
-            "in the future this will be a logical operation matching "
-            "Series.__xor__.  Use index.symmetric_difference(other) instead.",
-            FutureWarning,
-            stacklevel=find_stack_level(),
-        )
-        return self.symmetric_difference(other)
-
     @final
     def __nonzero__(self) -> NoReturn:
         raise ValueError(
@@ -6692,6 +6659,16 @@ def _cmp_method(self, other, op):
 
         return result
 
+    @final
+    def _logical_method(self, other, op):
+        res_name = ops.get_op_result_name(self, other)
+
+        lvalues = self._values
+        rvalues = extract_array(other, extract_numpy=True, extract_range=True)
+
+        res_values = ops.logical_op(lvalues, rvalues, op)
+        return self._construct_result(res_values, name=res_name)
+
     @final
     def _construct_result(self, result, name):
         if isinstance(result, tuple):

pandas/tests/indexes/datetimes/test_setops.py

@@ -305,8 +305,7 @@ def test_intersection_bug_1708(self):
         index_1 = date_range("1/1/2012", periods=4, freq="12H")
         index_2 = index_1 + DateOffset(hours=1)
 
-        with tm.assert_produces_warning(FutureWarning):
-            result = index_1 & index_2
+        result = index_1.intersection(index_2)
         assert len(result) == 0
 
     @pytest.mark.parametrize("tz", tz)

pandas/tests/indexes/multi/test_setops.py

@@ -111,13 +111,11 @@ def test_symmetric_difference(idx, sort):
 def test_multiindex_symmetric_difference():
     # GH 13490
     idx = MultiIndex.from_product([["a", "b"], ["A", "B"]], names=["a", "b"])
-    with tm.assert_produces_warning(FutureWarning):
-        result = idx ^ idx
+    result = idx.symmetric_difference(idx)
     assert result.names == idx.names
 
     idx2 = idx.copy().rename(["A", "B"])
-    with tm.assert_produces_warning(FutureWarning):
-        result = idx ^ idx2
+    result = idx.symmetric_difference(idx2)
     assert result.names == [None, None]
 
 

pandas/tests/indexes/numeric/test_setops.py

@@ -131,12 +131,6 @@ def test_symmetric_difference(self, sort):
             expected = expected.sort_values()
         tm.assert_index_equal(result, expected)
 
-        # __xor__ syntax
-        with tm.assert_produces_warning(FutureWarning):
-            expected = index1 ^ index2
-        assert tm.equalContents(result, expected)
-        assert result.name is None
-
 
 class TestSetOpsSort:
     @pytest.mark.parametrize("slice_", [slice(None), slice(0)])

pandas/tests/indexes/test_setops.py

@@ -191,20 +191,6 @@ def test_union_dtypes(left, right, expected, names):
     assert result.name == names[2]
 
 
-def test_dunder_inplace_setops_deprecated(index):
-    # GH#37374 these will become logical ops, not setops
-
-    with tm.assert_produces_warning(FutureWarning):
-        index |= index
-
-    with tm.assert_produces_warning(FutureWarning):
-        index &= index
-
-    is_pyarrow = str(index.dtype) == "string[pyarrow]" and pa_version_under7p0
-    with tm.assert_produces_warning(FutureWarning, raise_on_extra_warnings=is_pyarrow):
-        index ^= index
-
-
 @pytest.mark.parametrize("values", [[1, 2, 2, 3], [3, 3]])
 def test_intersection_duplicates(values):
     # GH#31326

pandas/tests/indexes/timedeltas/test_setops.py

@@ -101,15 +101,13 @@ def test_intersection_bug_1708(self):
         index_1 = timedelta_range("1 day", periods=4, freq="h")
         index_2 = index_1 + pd.offsets.Hour(5)
 
-        with tm.assert_produces_warning(FutureWarning):
-            result = index_1 & index_2
+        result = index_1.intersection(index_2)
         assert len(result) == 0
 
         index_1 = timedelta_range("1 day", periods=4, freq="h")
         index_2 = index_1 + pd.offsets.Hour(1)
 
-        with tm.assert_produces_warning(FutureWarning):
-            result = index_1 & index_2
+        result = index_1.intersection(index_2)
         expected = timedelta_range("1 day 01:00:00", periods=3, freq="h")
         tm.assert_index_equal(result, expected)
         assert result.freq == expected.freq

pandas/tests/series/test_arithmetic.py

@@ -729,7 +729,6 @@ def test_series_ops_name_retention(self, flex, box, names, all_binary_operators)
 
         name = op.__name__.strip("_")
         is_logical = name in ["and", "rand", "xor", "rxor", "or", "ror"]
-        is_rlogical = is_logical and name.startswith("r")
 
         right = box(right)
         if flex:
@@ -739,16 +738,7 @@ def test_series_ops_name_retention(self, flex, box, names, all_binary_operators)
             result = getattr(left, name)(right)
         else:
             # GH#37374 logical ops behaving as set ops deprecated
-            warn = FutureWarning if is_rlogical and box is Index else None
-            msg = "operating as a set operation is deprecated"
-            with tm.assert_produces_warning(warn, match=msg):
-                # stacklevel is correct for Index op, not reversed op
-                result = op(left, right)
-
-        if box is Index and is_rlogical:
-            # Index treats these as set operators, so does not defer
-            assert isinstance(result, Index)
-            return
+            result = op(left, right)
 
         assert isinstance(result, Series)
         if box in [Index, Series]:

pandas/tests/series/test_logical_ops.py

@@ -264,44 +264,26 @@ def test_logical_ops_with_index(self, op):
         result = op(ser, idx2)
         tm.assert_series_equal(result, expected)
 
-    @pytest.mark.filterwarnings("ignore:passing object-dtype arraylike:FutureWarning")
-    def test_reversed_xor_with_index_returns_index(self):
-        # GH#22092, GH#19792
+    def test_reversed_xor_with_index_returns_series(self):
+        # GH#22092, GH#19792 pre-2.0 these were aliased to setops
         ser = Series([True, True, False, False])
         idx1 = Index(
             [True, False, True, False], dtype=object
         )  # TODO: raises if bool-dtype
         idx2 = Index([1, 0, 1, 0])
 
-        msg = "operating as a set operation"
-
-        expected = Index.symmetric_difference(idx1, ser)
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            result = idx1 ^ ser
-        tm.assert_index_equal(result, expected)
+        expected = Series([False, True, True, False])
+        result = idx1 ^ ser
+        tm.assert_series_equal(result, expected)
 
-        expected = Index.symmetric_difference(idx2, ser)
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            result = idx2 ^ ser
-        tm.assert_index_equal(result, expected)
+        result = idx2 ^ ser
+        tm.assert_series_equal(result, expected)
 
     @pytest.mark.parametrize(
         "op",
         [
-            pytest.param(
-                ops.rand_,
-                marks=pytest.mark.xfail(
-                    reason="GH#22092 Index __and__ returns Index intersection",
-                    raises=AssertionError,
-                ),
-            ),
-            pytest.param(
-                ops.ror_,
-                marks=pytest.mark.xfail(
-                    reason="GH#22092 Index __or__ returns Index union",
-                    raises=AssertionError,
-                ),
-            ),
+            ops.rand_,
+            ops.ror_,
         ],
     )
     def test_reversed_logical_op_with_index_returns_series(self, op):
@@ -310,37 +292,31 @@ def test_reversed_logical_op_with_index_returns_series(self, op):
         idx1 = Index([True, False, True, False])
         idx2 = Index([1, 0, 1, 0])
 
-        msg = "operating as a set operation"
-
         expected = Series(op(idx1.values, ser.values))
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            result = op(ser, idx1)
+        result = op(ser, idx1)
         tm.assert_series_equal(result, expected)
 
-        expected = Series(op(idx2.values, ser.values))
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            result = op(ser, idx2)
+        expected = op(ser, Series(idx2))
+        result = op(ser, idx2)
         tm.assert_series_equal(result, expected)
 
     @pytest.mark.parametrize(
         "op, expected",
         [
-            (ops.rand_, Index([False, True])),
-            (ops.ror_, Index([False, True])),
-            (ops.rxor, Index([], dtype=bool)),
+            (ops.rand_, Series([False, False])),
+            (ops.ror_, Series([True, True])),
+            (ops.rxor, Series([True, True])),
         ],
     )
     def test_reverse_ops_with_index(self, op, expected):
         # https://github.com/pandas-dev/pandas/pull/23628
         # multi-set Index ops are buggy, so let's avoid duplicates...
+        # GH#49503
         ser = Series([True, False])
         idx = Index([False, True])
 
-        msg = "operating as a set operation"
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            # behaving as set ops is deprecated, will become logical ops
-            result = op(ser, idx)
-        tm.assert_index_equal(result, expected)
+        result = op(ser, idx)
+        tm.assert_series_equal(result, expected)
 
     def test_logical_ops_label_based(self):
         # GH#4947