construct expected results as DataFrame instead of FrozenList

Author: funnycrab

pandas/tests/tools/test_concat.py

@@ -1050,21 +1050,25 @@ def test_concat_multiindex_with_tz(self):
 
     def test_concat_multiindex_with_none_in_index_names(self):
         # GH 15787
-        from pandas.indexes.frozen import FrozenList
-
         index = pd.MultiIndex.from_product([[1], range(5)],
                                            names=['level1', None])
         df = pd.DataFrame({'col': range(5)}, index=index)
 
         result = concat([df, df], keys=[1, 2], names=['level2'])
-        result = result.index.names
-        expected = FrozenList(['level2', 'level1', None])
-        self.assertEqual(result, expected)
+        index = pd.MultiIndex.from_product([[1, 2], [1], range(5)],
+                                           names=['level2', 'level1', None])
+        expected = pd.DataFrame({'col': list(range(5)) * 2}, index=index)
+        assert_frame_equal(result, expected)
 
         result = concat([df, df[:2]], keys=[1, 2], names=['level2'])
-        result = result.index.names
-        expected = FrozenList(['level2', 'level1', None])
-        self.assertEqual(result, expected)
+        level2 = [1] * 5 + [2] * 2
+        level1 = [1] * 7
+        no_name = list(range(5)) + list(range(2))
+        tuples = list(zip(level2, level1, no_name))
+        index = pd.MultiIndex.from_tuples(tuples,
+                                          names=['level2', 'level1', None])
+        expected = pd.DataFrame({'col': no_name}, index=index)
+        assert_frame_equal(result, expected)
 
     def test_concat_keys_and_levels(self):
         df = DataFrame(np.random.randn(1, 3))