Adjust tests in window folder for new string option (#56182)

Author: phofl

pandas/tests/window/test_api.py

@@ -70,7 +70,9 @@ def tests_skip_nuisance(step):
 def test_sum_object_str_raises(step):
     df = DataFrame({"A": range(5), "B": range(5, 10), "C": "foo"})
     r = df.rolling(window=3, step=step)
-    with pytest.raises(DataError, match="Cannot aggregate non-numeric type: object"):
+    with pytest.raises(
+        DataError, match="Cannot aggregate non-numeric type: object|string"
+    ):
         # GH#42738, enforced in 2.0
         r.sum()
 

pandas/tests/window/test_groupby.py

@@ -1181,7 +1181,9 @@ def test_pairwise_methods(self, method, expected_data):
         )
         tm.assert_frame_equal(result, expected)
 
-        expected = df.groupby("A").apply(lambda x: getattr(x.ewm(com=1.0), method)())
+        expected = df.groupby("A")[["B"]].apply(
+            lambda x: getattr(x.ewm(com=1.0), method)()
+        )
         tm.assert_frame_equal(result, expected)
 
     def test_times(self, times_frame):