GNU bug report logs - #25187
Initialization of `shell-mode-map' is not safe

Previous Next

To add a comment to this bug, you must first unarchive it, by sending
a message to control AT debbugs.gnu.org, with unarchive 25187 in the body.
You can then email your comments to 25187 AT debbugs.gnu.org in the normal way.

Toggle the display of automated, internal messages from the tracker.

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Alexander Shukaev <emacs <at> Alexander.Shukaev.name>
To: bug-gnu-emacs <at> gnu.org
Subject: Initialization of `shell-mode-map' is not safe
Date: Tue, 13 Dec 2016 00:08:07 +0100

Hi,

consider

(defvar shell-mode-map
  (let ((map (nconc (make-sparse-keymap) comint-mode-map)))
    (define-key map "\C-c\C-f" 'shell-forward-command)
    (define-key map "\C-c\C-b" 'shell-backward-command)
    (define-key map "\t" 'completion-at-point)
    (define-key map (kbd "M-RET") 'shell-resync-dirs)
    (define-key map "\M-?" 'comint-dynamic-list-filename-completions)
    (define-key map [menu-bar completion]
      (cons "Complete"
	    (copy-keymap (lookup-key comint-mode-map [menu-bar completion]))))
    (define-key-after (lookup-key map [menu-bar completion])
      [complete-env-variable] '("Complete Env. Variable Name" .
				shell-dynamic-complete-environment-variable)
      'complete-file)
    (define-key-after (lookup-key map [menu-bar completion])
      [expand-directory] '("Expand Directory Reference" .
			   shell-replace-by-expanded-directory)
      'complete-expand)
    map))

from 'shell.el'.  When somebody decides to customize `comint-mode-map' 
by, for example, first wiping it out and then filling it again,

(with-eval-after-load 'comint	
  ;; Wipe `comint-mode-map':
  (setcdr comint-mode-map nil)
  ;; Fill `comint-mode-map':
  ...)

then when the `shell' feature is loaded, it will inevitably fail because 
`(lookup-key comint-mode-map [menu-bar completion])' may no longer 
return a keymap but rather nil or a number.

Looking forward for fix.

Regards,
Alexander

Message #10 received at 25187 <at> debbugs.gnu.org (full text, mbox):

From: Lars Ingebrigtsen <larsi <at> gnus.org>
To: Alexander Shukaev <emacs <at> Alexander.Shukaev.name>
Cc: 25187 <at> debbugs.gnu.org
Subject: Re: bug#25187: Initialization of `shell-mode-map' is not safe
Date: Wed, 09 Oct 2019 09:24:15 +0200

Alexander Shukaev <emacs <at> Alexander.Shukaev.name> writes:

> consider
>
> (defvar shell-mode-map
>   (let ((map (nconc (make-sparse-keymap) comint-mode-map)))

[...]

> from 'shell.el'.  When somebody decides to customize `comint-mode-map'
> by, for example, first wiping it out and then filling it again,
>
> (with-eval-after-load 'comint	
>   ;; Wipe `comint-mode-map':
>   (setcdr comint-mode-map nil)
>   ;; Fill `comint-mode-map':
>   ...)
>
> then when the `shell' feature is loaded, it will inevitably fail
> because `(lookup-key comint-mode-map [menu-bar completion])' may no
> longer return a keymap but rather nil or a number.

I've now fixed this in Emacs 27 by just removing the nconc from the
shell mode map -- shell-mode is derived from comint-mode, so it
automatically inherits its map.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.