BUG: Fix Series.append raises TypeError with tuple of Series

doc/source/whatsnew/v1.0.0.rst

@@ -234,7 +234,7 @@ Other
 - Trying to set the ``display.precision``, ``display.max_rows`` or ``display.max_columns`` using :meth:`set_option` to anything but a ``None`` or a positive int will raise a ``ValueError`` (:issue:`23348`)
 - Using :meth:`DataFrame.replace` with overlapping keys in a nested dictionary will no longer raise, now matching the behavior of a flat dictionary (:issue:`27660`)
 - :meth:`DataFrame.to_csv` and :meth:`Series.to_csv` now support dicts as ``compression`` argument with key ``'method'`` being the compression method and others as additional compression options when the compression method is ``'zip'``. (:issue:`26023`)
--
+- :meth:`Series.append` will no longer raise a ``TypeError`` when passed a tuple of ``Series`` (:issue:`28410`)
 
 .. _whatsnew_1000.contributors:
 

pandas/core/series.py

@@ -2730,7 +2730,8 @@ def append(self, to_append, ignore_index=False, verify_integrity=False):
         from pandas.core.reshape.concat import concat
 
         if isinstance(to_append, (list, tuple)):
-            to_concat = [self] + to_append
+            to_concat = [self]
+            to_concat.extend(to_append)
         else:
             to_concat = [self, to_append]
         return concat(

pandas/tests/series/test_combine_concat.py

@@ -54,6 +54,17 @@ def test_append_duplicates(self):
         with pytest.raises(ValueError, match=msg):
             pd.concat([s1, s2], verify_integrity=True)
 
+    def test_append_tuples(self):
+        # GH 28410
+        s = pd.Series([1, 2, 3])
+        list_input = [s, s]
+        tuple_input = (s, s)
+
+        expected = s.append(list_input)
+        result = s.append(tuple_input)
+
+        tm.assert_series_equal(expected, result)
+
     def test_combine_scalar(self):
         # GH 21248
         # Note - combine() with another Series is tested elsewhere because