Fix tests

Author: phofl

pandas/tests/frame/methods/test_align.py

@@ -107,7 +107,7 @@ def test_align_float(self, float_frame, using_copy_on_write):
             af, bf = float_frame.align(
                 other.iloc[:, 0], join="inner", axis=1, method=None, fill_value=None
             )
-        tm.assert_index_equal(bf.index, Index([]))
+        tm.assert_index_equal(bf.index, Index([]).astype(bf.index.dtype))
 
         msg = (
             "The 'method', 'limit', and 'fill_axis' keywords in DataFrame.align "
@@ -117,7 +117,7 @@ def test_align_float(self, float_frame, using_copy_on_write):
             af, bf = float_frame.align(
                 other.iloc[:, 0], join="inner", axis=1, method=None, fill_value=0
             )
-        tm.assert_index_equal(bf.index, Index([]))
+        tm.assert_index_equal(bf.index, Index([]).astype(bf.index.dtype))
 
         # Try to align DataFrame to Series along bad axis
         msg = "No axis named 2 for object type DataFrame"

pandas/tests/frame/methods/test_rank.py

@@ -476,7 +476,7 @@ def test_rank_object_first(
         obj = frame_or_series(["foo", "foo", None, "foo"])
         result = obj.rank(method="first", na_option=na_option, ascending=ascending)
         expected = frame_or_series(expected)
-        if using_infer_string:
+        if using_infer_string and isinstance(obj, Series):
             expected = expected.astype("uint64")
         tm.assert_equal(result, expected)