Update test

Author: dsaxton

pandas/tests/arithmetic/test_interval.py

@@ -273,19 +273,16 @@ def test_index_series_compat(self, op, constructor, expected_type, assert_func):
         assert_func(result, expected)
 
 
-@pytest.mark.parametrize("add", [True, False])
-def test_timestamp_interval_can_add_timedelta(add):
+@pytest.mark.parametrize("method", ["__add__", "__sub__"])
+def test_timestamp_interval_add_subtract_timedelta(method):
     # https://github.com/pandas-dev/pandas/issues/32023
-    interval = pd.Interval(
-        pd.Timestamp("2017-01-01 00:00:00"), pd.Timestamp("2018-01-01 00:00:00")
+    interval = Interval(
+        Timestamp("2017-01-01 00:00:00"), Timestamp("2018-01-01 00:00:00")
     )
-    delta = pd.Timedelta(days=7)
-
-    if add:
-        result = interval + delta
-        expected = pd.Interval(interval.left + delta, interval.right + delta)
-    else:
-        result = interval - delta
-        expected = pd.Interval(interval.left - delta, interval.right - delta)
+    delta = Timedelta(days=7)
+    result = getattr(interval, method)(delta)
+    left = getattr(interval.left, method)(delta)
+    right = getattr(interval.right, method)(delta)
+    expected = Interval(left, right)
 
     assert result == expected