GH1541 Revert Series[Any].__add__(str)

Author: loicdiridollou

pandas-stubs/core/series.pyi

@@ -1789,7 +1789,7 @@ class Series(IndexOpsMixin[S1], ElementOpsMixin[S1], NDFrame):
     # just failed to generate these so I couldn't match
     # them up.
     @overload
-    def __add__(self: Series[Never], other: complex | ListLike) -> Series: ...
+    def __add__(self: Series[Never], other: _str | complex | ListLike) -> Series: ...
     @overload
     def __add__(self, other: Index[Never] | Series[Never]) -> Series: ...
     @overload

tests/series/test_series.py

@@ -4080,3 +4080,11 @@ def test_series_index_setter() -> None:
     check(assert_type(sr.index, pd.Index), pd.Index)
     sr.index = [2, 3]
     check(assert_type(sr.index, pd.Index), pd.Index)
+
+
+def test_series_add_str() -> None:
+    """Test Series.__add__ with Series[Any]."""
+    df = pd.DataFrame({0: ["a", "b"]})
+    sr = df[0]
+
+    check(assert_type(sr.__add__("c1"), pd.Series), pd.Series, str)