fix: remove pandas.concat signature hook (#2173)

Signed-off-by: Ryo Kitagawa <kitadrum50@gmail.com>

Author: kitagry

pandera/mypy.py

@@ -64,11 +64,6 @@ def __init__(self, options) -> None:
         self.plugin_config = PanderaPluginConfig(options)
         super().__init__(options)
 
-    def get_function_signature_hook(self, fullname: str):
-        """Adjust the function signatures of pandas functions."""
-        if fullname == PANDAS_CONCAT:
-            return self.pandas_concat_callback
-
     def get_base_class_hook(
         self, fullname: str
     ) -> "Optional[Callable[[ClassDefContext], None]]":
@@ -87,30 +82,6 @@ def _pandera_model_class_maker_callback(
         transformer = DataFrameModelTransformer(ctx, self.plugin_config)
         transformer.transform()
 
-    def pandas_concat_callback(
-        self, ctx: Union[FunctionSigContext, MethodSigContext]
-    ) -> CallableType:
-        """Adjusts the signature pandas.concat to allow generator inputs."""
-        iterable = self.lookup_fully_qualified("typing.Iterable")
-        if iterable is not None:
-            iterable_node = cast(TypeInfo, iterable.node)
-        else:
-            raise ValueError("typing.Iterable node not found")
-
-        union_type = cast(UnionType, ctx.default_signature.arg_types[0])
-
-        pandas_data_type = ctx.default_signature.ret_type
-        arg_types = [
-            UnionType(
-                [
-                    Instance(iterable_node, [pandas_data_type]),
-                    *union_type.items,
-                ]
-            ),
-            *ctx.default_signature.arg_types[1:],
-        ]
-        return ctx.default_signature.copy_modified(arg_types=arg_types)
-
 
 class DataFrameModelTransformer:
     def __init__(self, ctx: ClassDefContext, plugin_config):

tests/mypy/test_pandas_static_type_checking.py

@@ -220,7 +220,10 @@ def test_pandas_stubs_false_positives(
         str(test_module_dir / "config" / config),
     ]
     # pylint: disable=subprocess-run-check
-    subprocess.run(commands, text=True)
+    result = subprocess.run(commands, text=True)
+    # NOTE: mypy return code is 0 if no errors were found, 1 if errors were found
+    # or 2 if there was a failure in checking
+    assert result.returncode in (0, 1)
     resulting_errors = _get_mypy_errors(module, capfd.readouterr().out)
     assert len(expected_errors) == len(resulting_errors)
     for expected, error in zip(expected_errors, resulting_errors):