TEST: added test case for issue 41800 (pandas-dev#50677)

* TEST: added test case for issue 41800

addresses pandas-dev#41800

* fix lint error

* fix lint error

* added assert_series_equal control and changed date_range call

pandas/tests/series/methods/test_combine_first.py

@@ -100,3 +100,16 @@ def test_combine_first_dt_tz_values(self, tz_naive_fixture):
         )
         exp = Series(exp_vals, name="ser1")
         tm.assert_series_equal(exp, result)
+
+    def test_combine_first_timezone_series_with_empty_series(self):
+        # GH 41800
+        time_index = date_range(
+            datetime(2021, 1, 1, 1),
+            datetime(2021, 1, 1, 10),
+            freq="H",
+            tz="Europe/Rome",
+        )
+        s1 = Series(range(10), index=time_index)
+        s2 = Series(index=time_index)
+        result = s1.combine_first(s2)
+        tm.assert_series_equal(result, s1)