Correct report_callback_exception type from attribute to method

stdlib/@tests/test_cases/check_tkinter.py

@@ -2,19 +2,17 @@
 
 import sys
 import tkinter
-import traceback
 import types
 from typing import Optional, Tuple
 from typing_extensions import assert_type
 
-
-def custom_handler(exc: type[BaseException], val: BaseException, tb: types.TracebackType | None) -> None:
-    print("oh no")
+root = tkinter.Tk()
+tkinter.Tk.report_callback_exception(root, TypeError, TypeError("no"), None)
 
 
-root = tkinter.Tk()
-root.report_callback_exception = traceback.print_exception
-root.report_callback_exception = custom_handler
+class App(tkinter.Tk):
+    def report_callback_exception(self, exc: type[BaseException], val: BaseException, tb: types.TracebackType | None) -> None:
+        print("oh no")
 
 
 def foo(x: int, y: str) -> None:

stdlib/@tests/test_cases/check_tkinter_method_assign.py

@@ -0,0 +1,20 @@
+# mypy: disable-error-code="method-assign"
+from __future__ import annotations
+
+import tkinter
+import traceback
+import types
+
+
+def custom_handler(exc: type[BaseException], val: BaseException, tb: types.TracebackType | None) -> None:
+    print("oh no")
+
+
+def custom_wrong_handler(exc: BaseException, val: BaseException, tb: types.TracebackType | None) -> None:
+    print("oh no")
+
+
+root = tkinter.Tk()
+root.report_callback_exception = traceback.print_exception
+root.report_callback_exception = custom_handler
+root.report_callback_exception = custom_wrong_handler  # type: ignore

stdlib/tkinter/__init__.pyi

@@ -1063,7 +1063,8 @@ class Tk(Misc, Wm):
     config = configure
     def destroy(self) -> None: ...
     def readprofile(self, baseName: str, className: str) -> None: ...
-    report_callback_exception: Callable[[type[BaseException], BaseException, TracebackType | None], object]
+    def report_callback_exception(self, exc: type[BaseException], val: BaseException, tb: TracebackType | None, /) -> object: ...
+
     # Tk has __getattr__ so that tk_instance.foo falls back to tk_instance.tk.foo
     # Please keep in sync with _tkinter.TkappType.
     # Some methods are intentionally missing because they are inherited from Misc instead.