update tests

Signed-off-by: Praateek <praateekm@gmail.com>

Author: praateekmahajan

pandas/tests/series/test_arithmetic.py

@@ -155,42 +155,25 @@ def _check_fill(meth, op, a, b, fill_value=0):
         # should accept axis=0 or axis='rows'
         op(a, b, axis=0)
 
-    def test_extarray_rhs_datetime_sub_with_fill_value(self):
-        # Ensure ExtensionArray (DatetimeArray) RHS is handled via array-like path
-        # and does not hit scalar isna branch.
-        left = Series(
-            [
-                pd.Timestamp("2025-08-20"),
-                pd.Timestamp("2025-08-21"),
-                pd.Timestamp("2025-08-22"),
-            ],
-            dtype=np.dtype("datetime64[ns]"),
-        )
-        right = left._values  # DatetimeArray
-
-        result = left.sub(right, fill_value=left.iloc[0])
-        # result dtype may vary (e.g., seconds vs ns), build expected from result dtype
-        expected = Series(np.zeros(3, dtype=np.dtype("timedelta64[ns]")))
-        tm.assert_series_equal(result, expected)
+    @pytest.mark.parametrize("kind", ["datetime", "timedelta"])
+    def test_rhs_extension_array_sub_with_fill_value(self, kind):
+        if kind == "datetime":
+            left = Series(
+                [pd.Timestamp("2025-08-20"), pd.Timestamp("2025-08-21")],
+                dtype=np.dtype("datetime64[ns]"),
+            )
+        else:
+            left = Series(
+                [Timedelta(days=1), Timedelta(days=2)],
+                dtype=np.dtype("timedelta64[ns]"),
+            )
 
-    def test_extarray_rhs_timedelta_sub_with_fill_value(self):
-        left = Series(
-            [Timedelta(days=1), Timedelta(days=2), Timedelta(days=3)],
-            dtype=np.dtype("timedelta64[ns]"),
-        )
-        right = left._values  # TimedeltaArray
+        right = (
+            left._values
+        )  # DatetimeArray or TimedeltaArray which is an ExtensionArray
 
         result = left.sub(right, fill_value=left.iloc[0])
-        expected = Series(np.zeros(3, dtype=np.dtype("timedelta64[ns]")))
-        tm.assert_series_equal(result, expected)
-
-    def test_extarray_rhs_period_eq_with_fill_value(self):
-        # Use equality to validate ExtensionArray RHS path for PeriodArray
-        left = Series(pd.period_range("2020Q1", periods=3, freq="Q"))
-        right = left._values  # PeriodArray
-
-        result = left.eq(right, fill_value=left.iloc[0])
-        expected = Series([True, True, True])
+        expected = Series(np.zeros(len(left), dtype=np.dtype("timedelta64[ns]")))
         tm.assert_series_equal(result, expected)
 
 
@@ -442,10 +425,16 @@ def test_comparison_flex_alignment(self, values, op):
         expected = Series(values, index=list("abcd"))
         tm.assert_series_equal(result, expected)
 
-    def test_extarray_rhs_categorical_eq_with_fill_value(self):
-        # Categorical RHS should be treated as array-like, not as scalar
-        left = Series(Categorical(["a", "b", "a"]))
-        right = left._values  # Categorical
+    @pytest.mark.parametrize(
+        "left",
+        [
+            Series(Categorical(["a", "b", "a"])),
+            Series(pd.period_range("2020Q1", periods=3, freq="Q")),
+        ],
+        ids=["categorical", "period"],
+    )
+    def test_rhs_extension_array_eq_with_fill_value(self, left):
+        right = left._values  # this is an ExtensionArray
 
         result = left.eq(right, fill_value=left.iloc[0])
         expected = Series([True, True, True])