for #410 (#413)

* for #410

added series in astypr

* up

* up2

Author: ramvikrams

pandas-stubs/core/frame.pyi

@@ -1359,7 +1359,7 @@ class DataFrame(NDFrame, OpsMixin):
     ) -> DataFrame: ...
     def astype(
         self,
-        dtype: _str | Dtype | dict[_str, _str | Dtype],
+        dtype: _str | Dtype | dict[_str, _str | Dtype] | Series,
         copy: _bool = ...,
         errors: _str = ...,
     ) -> DataFrame: ...

tests/test_frame.py

@@ -1921,3 +1921,9 @@ def df_accepting_dicts_iterator() -> None:
     # GH 392
     data = [{"a": 1, "b": 2}, {"a": 3, "b": 5}]
     check(assert_type(pd.DataFrame(iter(data)), pd.DataFrame), pd.DataFrame)
+
+
+def series_added_in_astype() -> None:
+    # GH410
+    df = pd.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6]})
+    check(assert_type(df.astype(df.dtypes), pd.DataFrame), pd.DataFrame)