BUG: Fix Series.reindex losing values when reindexing to MultiIndex - build test expected results

Author: Roline Stapny Saldanha

pandas/tests/frame/methods/test_reindex.py

@@ -1270,7 +1270,10 @@ def test_reindex_index_name_matches_multiindex_level(self):
         )
 
         result = df.reindex(index=target)
-        expected = df.reindex(index=target, level="a")
+        expected = DataFrame(
+            data={"value": [1, 1, 2, 2], "other": ["A", "A", "B", "B"]},
+            index=MultiIndex.from_product([[10, 20], ["x", "y"]], names=["a", "b"]),
+        )
         tm.assert_frame_equal(result, expected)
 
     def test_reindex_index_name_no_match_multiindex_level(self):
@@ -1279,7 +1282,7 @@ def test_reindex_index_name_no_match_multiindex_level(self):
 
         result = df.reindex(index=target)
         expected = DataFrame(
-            {"value": [np.nan] * 4},
+            data={"value": [np.nan] * 4},
             index=MultiIndex.from_product([[10, 20], ["x", "y"]], names=["a", "b"]),
         )
         tm.assert_frame_equal(result, expected)

pandas/tests/series/methods/test_reindex.py

@@ -453,8 +453,22 @@ def test_reindex_multiindex_automatic_level(name, expected_match_level_a):
     result = series.reindex(target)
 
     if expected_match_level_a:
-        expected = series.reindex(target, level="a")
+        expected = Series(
+            data=[26.73, 26.73, 24.255, 24.255],
+            index=MultiIndex.from_product(
+                [[81, 82], [np.nan], ["2018-06-01", "2018-07-01"]],
+                names=["a", "b", "c"],
+            ),
+            dtype=series.dtype,
+        )
     else:
-        expected = Series(np.nan, index=target, dtype=series.dtype)
+        expected = Series(
+            data=[np.nan] * 4,
+            index=MultiIndex.from_product(
+                [[81, 82], [np.nan], ["2018-06-01", "2018-07-01"]],
+                names=["a", "b", "c"],
+            ),
+            dtype=series.dtype,
+        )
 
     tm.assert_series_equal(result, expected)