Use fixtures in testing

Author: Dr-Irv

doc/source/whatsnew/v0.24.0.txt

@@ -411,7 +411,7 @@ Reshaping
 - Bug in :func:`pandas.concat` when joining resampled DataFrames with timezone aware index (:issue:`13783`)
 - Bug in :meth:`Series.combine_first` with ``datetime64[ns, tz]`` dtype which would return tz-naive result (:issue:`21469`)
 - Bug in :meth:`Series.where` and :meth:`DataFrame.where` with ``datetime64[ns, tz]`` dtype (:issue:`21546`)
--
+- Bug in :func:`Index.union` and :func:`Index.intersection` where name of the ``Index`` of the result was not computed correctly for certain cases (:issue:`9943`, :issue:`9862`)
 -
 
 Build Changes
@@ -425,6 +425,5 @@ Other
 
 - :meth: `~pandas.io.formats.style.Styler.background_gradient` now takes a ``text_color_threshold`` parameter to automatically lighten the text color based on the luminance of the background color. This improves readability with dark background colors without the need to limit the background colormap range. (:issue:`21258`)
 - Require at least 0.28.2 version of ``cython`` to support read-only memoryviews (:issue:`21688`)
-- Bug in :func:`Index.union` and :func:`Index.intersection` where name of the ``Index`` of the result was not computed correctly for certain cases (:issue:`9943`, :issue:`9862`)
 -
 -

pandas/core/indexes/base.py

@@ -2748,7 +2748,7 @@ def union(self, other):
         return self._wrap_setop_result(other, result)
 
     def _wrap_setop_result(self, other, result):
-        return self.__class__(result, name=get_op_result_name(self, other))
+        return self._constructor(result, name=get_op_result_name(self, other))
 
     def intersection(self, other):
         """

pandas/tests/indexes/conftest.py

@@ -14,6 +14,7 @@
                         tm.makeTimedeltaIndex(100),
                         tm.makeIntIndex(100),
                         tm.makeUIntIndex(100),
+                        tm.makeRangeIndex(100),
                         tm.makeFloatIndex(100),
                         Index([True, False]),
                         tm.makeCategoricalIndex(100),

pandas/tests/indexes/test_base.py

@@ -713,7 +713,10 @@ def test_empty_fancy_raises(self, attr):
 
     @pytest.mark.parametrize("itm", [101, 'no_int'])
     def test_getitem_error(self, indices, itm):
-        with pytest.raises(IndexError):
+        error_type = IndexError
+        if isinstance(indices, RangeIndex) and (itm == 'no_int'):
+            error_type = ValueError
+        with pytest.raises(error_type):
             indices[itm]
 
     def test_intersection(self):
@@ -793,43 +796,41 @@ def test_intersect_str_dates(self):
             (None, 'B', None),
             (None, None, None),
         ])
-    def test_corner_union(self, fname, sname, expected_name):
+    def test_corner_union(self, indices, fname, sname, expected_name):
         # GH 9943 9862
         # Test unions with various name combinations
-        # Do not test MultiIndex
+        # Do not test MultiIndex or repeats
 
-        skip_index_keys = ['tuples', 'repeats']
-        for key, id in self.indices.items():
-            if key in skip_index_keys:
-                continue
+        if isinstance(indices, MultiIndex) or not indices.is_unique:
+            pytest.skip("Not for MultiIndex or repeated indices")
+
+        # Test copy.union(copy)
+        first = indices.copy().set_names(fname)
+        second = indices.copy().set_names(sname)
+        union = first.union(second)
+        expected = indices.copy().set_names(expected_name)
+        tm.assert_index_equal(union, expected)
+
+        # Test copy.union(empty)
+        first = indices.copy().set_names(fname)
+        second = indices.drop(indices).set_names(sname)
+        union = first.union(second)
+        expected = indices.copy().set_names(expected_name)
+        tm.assert_index_equal(union, expected)
+
+        # Test empty.union(copy)
+        first = indices.drop(indices).set_names(fname)
+        second = indices.copy().set_names(sname)
+        union = first.union(second)
+        expected = indices.copy().set_names(expected_name)
+        tm.assert_index_equal(union, expected)
 
-            # Test copy.union(copy)
-            first = id.copy().set_names(fname)
-            second = id.copy().set_names(sname)
-            union = first.union(second)
-            expected = id.copy().set_names(expected_name)
-            tm.assert_index_equal(union, expected)
-
-            # Test copy.union(empty)
-            first = id.copy().set_names(fname)
-            second = id.drop(id).set_names(sname)
-            union = first.union(second)
-            expected = id.copy().set_names(expected_name)
-            tm.assert_index_equal(union, expected)
-
-            # Test empty.union(copy)
-            first = id.drop(id).set_names(fname)
-            second = id.copy().set_names(sname)
-            union = first.union(second)
-            expected = id.copy().set_names(expected_name)
-            tm.assert_index_equal(union, expected)
-
-            # Test empty.union(empty)
-            first = id.drop(id).set_names(fname)
-            second = id.drop(id).set_names(sname)
-            union = first.union(second)
-            expected = id.drop(id).set_names(expected_name)
-            tm.assert_index_equal(union, expected)
+        # Test empty.union(empty)
+        first = indices.drop(indices).set_names(fname)
+        second = indices.drop(indices).set_names(sname)
+        union = first.union(second)
+        expected = indices.drop(indices).set_names(expected_name)
+        tm.assert_index_equal(union, expected)
 
     def test_chained_union(self):
         # Chained unions handles names correctly
@@ -2533,6 +2534,10 @@ def test_generated_op_names(opname, indices):
         # pd.Index.__rsub__ does not exist; though the method does exist
         # for subclasses.  see GH#19723
         return
+    if (isinstance(index, RangeIndex) and
+        opname in ['add', 'radd', 'sub', 'rsub',
+                   'mul', 'rmul', 'truediv', 'rtruediv']):
+        pytest.skip("RangeIndex does operators differently")
     opname = '__{name}__'.format(name=opname)
     method = getattr(index, opname)
     assert method.__name__ == opname