gh-88516: show file proxy icon in IDLE editor windows on macOS

Lib/idlelib/editor.py

@@ -1043,7 +1043,9 @@ def open_recent_file(fn_closure=file_name):
     def saved_change_hook(self):
         short = self.short_title()
         long = self.long_title()
-        if short and long:
+        if short and long and not macosx.isCocoaTk():
+            # Don't use both values on macOS because
+            # that doesn't match platform conventions.
             title = short + " - " + long + _py_version
         elif short:
             title = short
@@ -1058,6 +1060,13 @@ def saved_change_hook(self):
         self.top.wm_title(title)
         self.top.wm_iconname(icon)
 
+        if macosx.isCocoaTk():
+            # Add a proxy icon to the window title
+            self.top.wm_attributes("-titlepath", long)
+
+            # Maintain the modification status for the window
+            self.top.wm_attributes("-modified", not self.get_saved())
+
     def get_saved(self):
         return self.undo.get_saved()
 

Misc/NEWS.d/next/IDLE/2023-12-09-11-04-26.gh-issue-88516.SIIvfs.rst

@@ -0,0 +1,2 @@
+On macOS show a proxy icon in the title bar of editor windows to match
+platform behaviour.