gh-112898: warn about unsaved files when quitting IDLE on macOS (#112939)

* gh-112898: warn about unsaved files when quitting IDLE on macOS

Implement the TK function ``::tk::mac::Quit`` on macOS to
ensure that IDLE asks about saving unsaved files when
quitting IDLE. 

Co-authored-by: Christopher Chavez [email protected]

Author: ronaldoussoren

Lib/idlelib/macosx.py

@@ -221,7 +221,7 @@ def help_dialog(event=None):
         # The binding above doesn't reliably work on all versions of Tk
         # on macOS. Adding command definition below does seem to do the
         # right thing for now.
-        root.createcommand('exit', flist.close_all_callback)
+        root.createcommand('::tk::mac::Quit', flist.close_all_callback)
 
     if isCarbonTk():
         # for Carbon AquaTk, replace the default Tk apple menu

Misc/NEWS.d/next/IDLE/2023-12-10-20-01-11.gh-issue-112898.98aWv2.rst

@@ -0,0 +1 @@
+Fix processing unsaved files when quitting IDLE on macOS.