bug#6527: C-h b alters key-translation-map (in a bad way)

bug#6527: C-h b alters key-translation-map (in a bad way)

[David Reitter]

X-debbugs-cc: larry@denenberg.com

C-h b alters the key translation map.


Emacs
(setq ns-command-modifier 'alt)  ;; On NS, we need to assign the modifier key
Press Command-C -> A-c is undefined (correct)
C-h b
Press Command-C -> ¢ is inserted


The value of `key-translation-map' is indeed changed by C-h b, and resetting it fixes the problem.

Some debugging suggests that something odd is happening in describe_map(). Commenting out

  map = call1 (Qkeymap_canonicalize, map);

makes the error go away.  A direct call to `keymap-canonicalize' does not, however, reproduce it, so there is something else going on.


Full credit for the original report of a reproducible bug goes to Larry Denenberg - his report is quoted below.



In GNU Emacs 23.2.50.1 (x86_64-apple-darwin10.3.1, NS apple-appkit-1038.29)
 of 2010-05-10 on elin.psy.cmu.edu
Windowing system distributor `Apple', version 10.3.1038
configured using `configure  '--with-ns''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: nil
  value of $XMODIFIERS: nil
  locale-coding-system: nil
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  which-function-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<help-echo> C-x k <return> ) s e <backspace> <backspace> 
<backspace> ( s e t q SPC n s - a <backspace> c o m 
m a n d - m o d i f i e r SPC ' a l t ) C-x C-e <return> 
A-c A-c <down> <down> C-h b <help-echo> <down-mouse-1> 
<mouse-1> A-c A-c <help-echo> <menu-bar> <help-menu> 
<send-emacs-bug-report>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Unable to load color "darkblue"
alt
Type C-x 1 to delete the help window, C-M-v to scroll help.

Load-path shadows:
None found.

Features:
(shadow sort mail-extr message ecomplete rfc822 mml mml-sec
password-cache mm-decode mm-bodies mm-encode mailcap mail-parse rfc2231
rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader gnus-util netrc
time-date mm-util mail-prsvr gmm-utils wid-edit mailheader canlock sha1
hex-util hashcash mail-utils emacsbug kmacro two-column iso-transl
help-mode view ghostedit ghostedit-stopwords-en easy-mmode which-func
imenu tooltip ediff-hook vc-hooks lisp-float-type mwheel ns-win easymenu
tool-bar dnd fontset image fringe lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mldrag mouse jit-lock font-lock
syntax facemenu font-core frame cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
case-table epa-hook jka-cmpr-hook help simple abbrev loaddefs button
minibuffer faces cus-face files text-properties overlay md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process ns multi-tty emacs)

===



Begin forwarded message:

> From: Larry Denenberg <larry@denenberg.com>
> Date: June 25, 2010 7:02:32 AM EDT
> To: aquamacs-bugs@aquamacs.org
> Cc: larry@denenberg.com
> Subject: [Aquamacs-bugs] 23.2; ^H B doesn't just describe bindings, it changes them
> Reply-To: Bug reports for Aquamacs Emacs <aquamacs-bugs@aquamacs.org>
> 
> 
> Starting from scratch, type ^H C ⌘. [that's C-h A-.) to get
>        ⌘. runs the command keyboard-quit
> 
> Then type ^H B to see a help buffer describing key bindings, after
> which ^H C ⌘. again (in any buffer) yields
>        · (translated from ⌘.) runs the command self-insert-command
> 
> Note that the first character here is not a period but a centered dot, #xb7.
> 
> BTW, after you've done this, you get "Options have changed - save them?"
> upon exit.
> 
> I get this behavior in Aquamacs as described below, whether starting
> "-q" or "-Q", and also in 24.0.50.1.  I do not get it in 22.3.1, nor in
> plain GNU Emacs 24.0.50.2.
> 
> /Larry Denenberg
> larry@denenberg.com
> http://larry.denenberg.com/
> 
> 
> In GNU Emacs 23.2.1 (i386-apple-darwin9.8.0, NS apple-appkit-949.54)
> of 2010-05-09 on braeburn.aquamacs.org - Aquamacs Distribution 2.0
> Windowing system distributor `Apple', version 10.3.1038
> configured using `configure  '--with-ns' '--without-x' 'CFLAGS=-arch i386 -arch ppc' 'LDFLAGS=-arch i386 -arch ppc''
> 
> Important settings:
>  value of $LC_ALL: nil
>  value of $LC_COLLATE: nil
>  value of $LC_CTYPE: nil
>  value of $LC_MESSAGES: nil
>  value of $LC_MONETARY: nil
>  value of $LC_NUMERIC: nil
>  value of $LC_TIME: nil
>  value of $LANG: en_US.UTF-8
>  value of $XMODIFIERS: nil
>  locale-coding-system: utf-8-unix
>  default enable-multibyte-characters: t
> 
> Major mode: Text
> 
> Minor modes in effect:
>  savehist-mode: t
>  smart-frame-positioning-mode: t
>  aquamacs-autoface-mode: t
>  recentf-mode: t
>  osx-key-mode: t
>  tabbar-mwheel-mode: t
>  tabbar-mode: t
>  show-paren-mode: t
>  delete-selection-mode: t
>  pc-selection-mode: t
>  cua-mode: t
>  tooltip-mode: t
>  mouse-wheel-mode: t
>  tool-bar-mode: t
>  menu-bar-mode: t
>  file-name-shadow-mode: t
>  global-font-lock-mode: t
>  font-lock-mode: t
>  blink-cursor-mode: t
>  auto-encryption-mode: t
>  auto-compression-mode: t
>  smart-spacing-mode: t
>  column-number-mode: t
>  line-number-mode: t
>  visual-line-mode: t
>  transient-mark-mode: t
> 
> Recent input:
> <ns-application-activated> ^H C ⌘. ^H B ^H C ⌘. ^X 
> O ^H O <help-echo> <help-echo> <help-echo> <help-echo> 
> <help-echo> <switch-frame> ^H C ⌘. <menu-bar> <help-menu> 
> <bug-diagnosis> <start-vanilla-aquamacs> <menu-bar> 
> <help-menu> <bug-diagnosis> <send-emacs-bug-report
>> 
> 
> Recent messages:
> Cleaning up the recentf list...done (0 removed)
> 29 environment variables imported from login shell (/bin/bash).
> Loading /Applications/Aquamacs.app/Contents/Resources/lisp/aquamacs/edit-modes/auctex.el (source)...done
> Loading /Applications/Aquamacs.app/Contents/Resources/lisp/aquamacs/edit-modes/haskell-mode/haskell-site-file.el (source)...done
> one-buffer-one-frame-mode disabled.
> Mark set [32 times]
> Aquamacs is based on GNU Emacs, a part of the GNU/Linux system. It is Free Software: you can improve and redistribute it under the GNU General Public License, version 3 or later. Copyright (C) 2010 Free Software Foundation, Inc. (C) 2010 D. Reitter. No Warranty.
> ⌘. runs the command keyboard-quit
> Type "q" to quit, M-x scroll-up to scroll help.
> · (translated from ⌘.) runs the command self-insert-command [2 times]
> start-vanilla-aquamacs: Searching for program: no such file or directory, Aquamacs.app/Contents/MacOS/Aquamacs
> 
> Load-path shadows:
> None found.
> 
> Features:
> (shadow sort mail-extr message ecomplete rfc822 mml mml-sec
> password-cache mm-decode mm-bodies mm-encode mailcap mail-parse rfc2231
> rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader gnus-util netrc
> mm-util mail-prsvr gmm-utils mailheader canlock sha1 hex-util hashcash
> mail-utils emacsbug kmacro two-column iso-transl aquamacs-mode-defaults
> auctex-config server tex-site smart-dnd aquamacs-aux savehist mouse-sel
> one-buffer-one-frame smart-frame-positioning drews_init
> color-theme-autoloads saveplace visual-line aquamacs-bug
> aquamacs-autoface-mode aquamacs-editing sendmail recentf tree-widget
> cus-edit osxkeys emulate-mac-keyboard-mode frame-cmds strings misc-fns
> thingatpt+ thingatpt frame-fns avoid aquamacs-mac-fontsets fit-frame
> aquamacs-frame-setup aquamacs-tabbar tabbar-window cl cl-19 tabbar
> easy-mmode cus-start cus-load aquamacs-site-start cocoa-compatibility
> filladapt aquamacs-redo check-for-updates aquamacs-menu osx_defaults
> aquamacs-tool-bar aquamacs mac-extra-functions aquamacs-tools
> aquamacs-macros parse-time timezone time-date paren delsel pc-select
> cua-base wid-edit regexp-opt advice advice-preload byte-opt bytecomp
> byte-compile debug help-fns help-mode view image-file disp-table tooltip
> ediff-hook vc-hooks lisp-float-type mwheel ns-win easymenu tool-bar dnd
> fontset image fringe lisp-mode register page menu-bar rfn-eshadow timer
> select scroll-bar mldrag mouse jit-lock font-lock syntax facemenu
> font-core frame cham georgian utf-8-lang misc-lang vietnamese tibetan
> thai tai-viet lao korean japanese hebrew greek romanian slovak czech
> european ethiopic indian cyrillic chinese case-table epa-hook
> jka-cmpr-hook help simple abbrev loaddefs button minibuffer faces
> cus-face files text-properties overlay md5 base64 format env code-pages
> mule custom widget hashtable-print-readable backquote
> make-network-process ns multi-tty emacs)
> 
> Command line: (Aquamacs.app/Contents/MacOS/Aquamacs)
> 
> PATH: /Users/larry/Bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/nmh/bin:/usr/local/bin:/usr/local/mysql/bin:/usr/texbin:/opt/subversion/bin:/usr/lib:/Users/larry/Bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/nmh/bin:/usr/local/bin:/usr/local/mysql/bin:/usr/texbin:/opt/subversion/bin:/usr/lib:/usr/texbin:/usr/local/texlive/2008/bin
> 
> exec-path: (/Users/larry/Bin /bin /sbin /usr/bin /usr/sbin /usr/local/nmh/bin /usr/local/bin /usr/local/mysql/bin /usr/texbin /opt/subversion/bin /usr/lib /Users/larry/Bin /bin /sbin /usr/bin /usr/sbin /usr/local/nmh/bin /usr/local/bin /usr/local/mysql/bin /usr/texbin /opt/subversion/bin /usr/lib /Applications/Aquamacs.app/Contents/MacOS/bin /usr/local/texlive/2008/bin)
> _______________________________________________
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> http://lists.aquamacs.org/mailman/listinfo.cgi/aquamacs-bugs

bug#6527: C-h b alters key-translation-map (in a bad way)

[David Reitter]

I have reduced bug 6527 to this:

(map-keymap-internal 'ignore 'iso-transl-ctl-x-8-map)

(as called via `keymap_canonicalize')

or also

(keymap-parent  'iso-transl-ctl-x-8-map)

because it seems to be the call to get_keymap with autoloading that is causing it.

Indeed we have the following autoload:

;;;***
;;;### (autoloads nil "iso-transl" "international/iso-transl.el"
;;;;;;  (19423 17168))
;;; Generated autoloads from international/iso-transl.el
 (or key-translation-map (setq key-translation-map (make-sparse-keymap)))
 (define-key key-translation-map "\C-x8" 'iso-transl-ctl-x-8-map)
 (autoload 'iso-transl-ctl-x-8-map "iso-transl" "Keymap for C-x 8 prefix." t 'keymap)


And, merely loading iso-trans.el is documented to create keybindings with Alt.

iso-transl pach (bug#6527: C-h b alters key-translation-map (in a bad way))

[David Reitter]

I reported bug 6527 a while ago.

> 6527: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=6527

The problem was that iso-trans.el is autoloaded (e.g., when doing C-h b) and unconditionally binds Alt key combinations, overriding any user/package defined A- keys.  Once loaded, there is no obvious way to undo those bindings.

Here's a fix for this.  It defines a new minor mode, `iso-transl-mode', which controls those A-... key bindings.
I chose to automatically define the C-x 8 prefix key combinations when the package is loaded, so that the C-x 8 autoloading mechanism remains in place for the comfort of the occasional user. 

I don't know how much iso-transl is used by people, so I can't gauge the impact of this.  Please advise.



diff --combined lisp/international/iso-transl.el
index 8a88b50,b11a7a2..0000000
--- a/lisp/international/iso-transl.el
+++ b/lisp/international/iso-transl.el
@@@ -25,21 -25,16 +25,21 @@@
  ;;; Commentary:
  
  ;; Loading this package defines three ways of entering the non-ASCII
 -;; printable characters with codes above 127: the prefix C-x 8, or the
 -;; Alt key, or a dead accent key.  For example, you can enter uppercase
 -;; A-umlaut as `C-x 8 " A' or `Alt-" A' (if you have an Alt key) or
 -;; `umlaut A' (if you have an umlaut/diaeresis key).
 +;; printable characters with codes above 127: the prefix C-x 8, and,
 +;; with `iso-transl-mode' enabled, also the Alt key, and a dead accent
 +;; key.  For example, you can enter uppercase A-umlaut as `C-x 8 " A'
 +;; or, `iso-transl-mode' is enabled, `Alt-" A' (if you have an Alt
 +;; key) or `umlaut A' (if you have an umlaut/diaeresis key).
  
 -;; C-x 8 is set up to autoload this package,
 -;; but Alt keys and dead accent keys are only defined
 -;; once you have loaded the package.  It is nontrivial
 -;; to make all of the Alt keys autoload, and it is not clear
 -;; that the dead accent keys SHOULD autoload this package.
 +;; C-x 8 is set up to autoload this package, but Alt keys and dead
 +;; accent keys are only defined once you have loaded the package and
 +;; enabled `iso-transl-mode'.  It is nontrivial to make all of the Alt
 +;; keys autoload, and it is not clear that the dead accent keys SHOULD
 +;; autoload this package.
 +
 +;; Note that C-h b will autoload this package, which is one reason
 +;; why the more destructive key sequences (without C-x 8 prefix) are
 +;; only defined in `iso-transl-mode', and are thus reversible.
  
  ;;; Code:
  
@@@ -252,41 -247,29 +252,41 @@@ sequence VECTOR.  (VECTOR is normally o
      (setq key-translation-map (make-sparse-keymap)))
  (define-key key-translation-map "\C-x8" iso-transl-ctl-x-8-map)
  
 +(defmacro iso-transl-define-key (keymap key def)
 +  "Back up definition of KEY in KEYMAP, then `define-key'."
 +  `(progn
 +     (push (cons ,key (or (lookup-key ,keymap ,key) 'none))
 +	   (get ',keymap 'iso-transl-backup))
 +     (define-key ,keymap ,key ,def)))
 +
  ;; For each entry in the alist, we'll make up to three ways to generate
  ;; the character in question: the prefix `C-x 8'; the ALT modifier on
  ;; the first key of the sequence; and (if applicable) replacing the first
  ;; key of the sequence with the corresponding dead key.  For example, a
  ;; character associated with the string "~n" can be input with `C-x 8 ~ n'
  ;; or `Alt-~ n' or `mute-asciitilde n'.
 +(defun iso-transl-define-prefix-keys (alist)
 +  (while alist
 +    (let ((translated-vec (cdr (car alist))))
 +      (iso-transl-define-key iso-transl-ctl-x-8-map (car (car alist)) translated-vec))
 +    (setq alist (cdr alist))))
  (defun iso-transl-define-keys (alist)
    (while alist
      (let ((translated-vec (cdr (car alist))))
 -      (define-key iso-transl-ctl-x-8-map (car (car alist)) translated-vec)
 +      ;(iso-transl-define-key iso-transl-ctl-x-8-map (car (car alist)) translated-vec)
        (let ((inchar (aref (car (car alist)) 0))
  	    (vec (vconcat (car (car alist))))
  	    (tail iso-transl-dead-key-alist))
  	(aset vec 0 (logior (aref vec 0) ?\A-\^@))
 -	(define-key key-translation-map vec translated-vec)
 -	(define-key isearch-mode-map (vector (aref vec 0)) nil)
 +	(iso-transl-define-key key-translation-map vec translated-vec)
 +	(iso-transl-define-key isearch-mode-map (vector (aref vec 0)) nil)
  	(while tail
  	  (if (eq (car (car tail)) inchar)
  	      (let ((deadvec (copy-sequence vec))
  		    (deadkey (cdr (car tail))))
  		(aset deadvec 0 deadkey)
 -		(define-key isearch-mode-map (vector deadkey) nil)
 -		(define-key key-translation-map deadvec translated-vec)))
 +		(iso-transl-define-key isearch-mode-map (vector deadkey) nil)
 +		(iso-transl-define-key key-translation-map deadvec translated-vec)))
  	  (setq tail (cdr tail)))))
      (setq alist (cdr alist))))
  
@@@ -297,45 -280,14 +297,45 @@@
    (iso-transl-define-keys (cdr (assoc lang iso-transl-language-alist))))
  
  
 -;; The standard mapping comes automatically.  You can partially overlay it
 -;; with a language-specific mapping by using `M-x iso-transl-set-language'.
 -(iso-transl-define-keys iso-transl-char-map)
 -
 +;; unconditional definitions
 +(iso-transl-define-prefix-keys iso-transl-char-map)
  (define-key isearch-mode-map "\C-x" nil)
  (define-key isearch-mode-map [?\C-x t] 'isearch-other-control-char)
  (define-key isearch-mode-map "\C-x8" nil)
  
 +(define-minor-mode iso-transl-mode
 + "ISO Key translation mode.
 +This mode defines two ways of entering the non-ASCII printable
 +characters with codes above 127: the Alt key and 
 +a dead accent key.  For example, you can enter uppercase A-umlaut as
 +`Alt-\" A' (if you have an Alt key) or `umlaut A' (if
 +you have an umlaut/diaeresis key).
 +
 +This character can always be entered as `C-x 8 \" A' regardless of
 +this mode."
 + :group 'i18n
 + :lighter " ISO"
 +
 + (if iso-transl-mode
 +     ;; The standard mapping comes automatically.  You can partially overlay it
 +     ;; with a language-specific mapping by using `M-x iso-transl-set-language'.
 +     (iso-transl-define-keys iso-transl-char-map)
 +   (mapc
 +    (lambda (key-def) 
 +      (define-key key-translation-map (car key-def) 
 +	(and (not (eq (cdr key-def) 'none)) (cdr key-def))))
 +    (nreverse (get 'key-translation-map 'iso-transl-backup)))
 +   (put 'key-translation-map 'iso-transl-backup nil)
 +   (mapc
 +    (lambda (key-def) 
 +      (condition-case nil
 +	  (define-key isearch-mode-map (car key-def) 
 +	    (and (not (eq (cdr key-def) 'none)) (cdr key-def)))
 +	;; if some of the unconditional definitions above are instead made conditional
 +	;; restoring the default keys fails.
 +	(error nil)))
 +    (nreverse (get 'isearch-mode-map 'iso-transl-backup)))
 +   (put 'isearch-mode-map 'iso-transl-backup nil)))
  
  (provide 'iso-transl)
  

Re: iso-transl pach (bug#6527: C-h b alters key-translation-map (in a bad way))

[Stefan Monnier]

> I chose to automatically define the C-x 8 prefix key combinations when
> the package is loaded, so that the C-x 8 autoloading mechanism remains
> in place for the comfort of the occasional user. 

I agree we need to decouple the 3 parts:
- the C-x 8 should stay, and could be extended to cover many more cases
  (e.g. C-x 8 r ' could insert ŕ, etc...)
- the Alt- bindings (could be under the control of a minor mode, like
  your patch does).
- the deadkey handling, which IIUC should be handled automatically by
  other parts of the code.

So, I think your patch goes in the right direction, except that the
deadkey handling should be either removed (because it doesn't do
anything any way) or always enabled.


        Stefan

bug#6527: C-h b alters key-translation-map (in a bad way)

[Lars Ingebrigtsen]

David Reitter <david.reitter@gmail.com> writes:

> C-h b alters the key translation map.

In Emacs 28, Emacs is preloaded with iso-transl, so this no longer
happens.  I'm therefore closing this bug report.

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