bpo-45296: Fix exit/quit message on Windows (GH-28577)

IDLE recognizes Ctrl-D, as on other systems, instead of Ctrl-Z.

Lib/idlelib/pyshell.py

@@ -66,6 +66,13 @@ use_subprocess = False
 HOST = '127.0.0.1' # python execution server on localhost loopback
 PORT = 0  # someday pass in host, port for remote debug capability
 
+try:  # In case IDLE started with -n.
+    eof = 'Ctrl-D (end-of-file)'
+    exit.eof = eof
+    quit.eof = eof
+except NameError: # In case python started with -S.
+    pass
+
 # Override warnings module to write to warning_stream.  Initialize to send IDLE
 # internal warnings to the console.  ScriptBinding.check_syntax() will
 # temporarily redirect the stream to the shell window to display warnings when

Lib/idlelib/run.py

@@ -40,6 +40,13 @@ if not hasattr(sys.modules['idlelib.run'], 'firstrun'):
 
 LOCALHOST = '127.0.0.1'
 
+try:
+    eof = 'Ctrl-D (end-of-file)'
+    exit.eof = eof
+    quit.eof = eof
+except NameError: # In case subprocess started with -S (maybe in future).
+    pass
+
 
 def idle_formatwarning(message, category, filename, lineno, line=None):
     """Format warnings the IDLE way."""