Add failing test for empty boolean Categoricals

Author: pganssle

pandas/tests/arrays/categorical/test_constructors.py

@@ -42,6 +42,13 @@ def test_constructor_empty(self):
         expected = pd.Int64Index([1, 2, 3])
         tm.assert_index_equal(c.categories, expected)
 
+    @pytest.mark.xfail
+    def test_constructor_empty_boolean(self):
+        # see gh-22702
+        cat = pd.CategoricalIndex([], categories=[True, False])
+        categories = sorted(cat.categories.tolist())
+        assert categories == [False, True]
+
     def test_constructor_tuples(self):
         values = np.array([(1,), (1, 2), (1,), (1, 2)], dtype=object)
         result = Categorical(values)