bug#19384: 24.4; variable-pitch-mode should turn itself on when passed nil

[João Távora]

Stefan Monnier <monnier@iro.umontreal.ca> writes:
> Indeed.  Could you make it a bug report?

The minor mode `variable-pitch-mode' should turn itself on when passed
nil as the value of its ARG parameter, cccording to minor-mode
standards.

This is so that placing the symbol `variable-pitch-mode' in any hook
does the intuitive thing: i.e. ensure the mode is turned on. Currently
it might toggle the mode off if it is already on.

The actual problem may live in `buffer-face-mode-invoke', whose
docstring states that its ARG parameter is "interpreted in the usual
manner for minor-mode commands". That is not true, since passing it as
NIL causes `buffer-face-toggle' to be called. It's probably safe to fix
it here since it's apparently only used in two places:

    ./face-remap.el:422:(defun buffer-face-mode-invoke (specs arg &optional 
interactive)
    ./face-remap.el:458:  (buffer-face-mode-invoke 'variable-pitch arg
    ./mouse.el:1836:(declare-function buffer-face-mode-invoke "face-remap"
    ./mouse.el:1896:             (buffer-face-mode-invoke

João


In GNU Emacs 24.4.1 (i686-pc-mingw32)
 of 2014-10-24 on LEG570
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --prefix=/c/usr'

Important settings:
  value of $LC_CTYPE: UTF-8
  value of $LANG: C.UTF-8
  locale-coding-system: cp1252

Major mode: Lisp

Minor modes in effect:
  diff-auto-refine-mode: t
  yas-global-mode: t
  yas-minor-mode: t
  shell-dirtrack-mode: t
  sly-stickers-shortcut-mode: t
  sly-stickers-mode: t
  sly-profiler-shortcut-mode: t
  sly-trace-dialog-shortcut-mode: t
  sly-autodoc-mode: t
  eldoc-mode: t
  sly-editing-mode: t
  sly-mode: t
  global-edit-server-edit-mode: t
  electric-pair-mode: t
  ido-everywhere: t
  delete-selection-mode: t
  global-auto-revert-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t
  hs-minor-mode: t

Recent input:
C-n C-n C-n C-n C-n C-n C-n C-p C-p C-p C-p C-p C-p 
C-p C-p C-p C-p C-p C-p C-p C-p C-p C-e M-b M-b M-b 
M-b C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n 
C-n C-n C-n C-a C-a C-k C-k M-< C-e M-b M-b M-b M-b 
C-b a v o r a C-f M-d g m a i l C-f M-d c o m C-c C-c 
C-g C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n 
C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n 
C-f C-p C-f C-b m o r e SPC M-q C-p C-n <M-backspace> 
m o s t SPC M-b M-b M-d i t s M-q C-p C-n C-e C-x C-s 
C-p C-n C-p C-p C-p C-p C-p C-p C-n C-n C-n C-c C-c 
y C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-x 1 <wheel-down> 
<double-wheel-down> <wheel-down> <wheel-down> <wheel-down> 
<wheel-down> <wheel-down> <wheel-down> <wheel-down> 
<wheel-down> <wheel-down> <double-wheel-down> <wheel-down> 
<wheel-up> <double-wheel-up> <wheel-down> <double-wheel-down> 
<triple-wheel-down> <triple-wheel-down> <wheel-up> 
<double-wheel-up> <down-mouse-1> <mouse-1> <wheel-down> 
<down-mouse-1> <mouse-1> <down-mouse-1> <mouse-1> <wheel-down> 
<wheel-down> <double-wheel-down> <triple-wheel-down> 
<wheel-down> <double-wheel-down> <triple-wheel-down> 
<wheel-down> <double-wheel-down> <triple-wheel-down> 
<wheel-down> <double-wheel-down> <triple-wheel-down> 
<wheel-down> <double-wheel-down> <down-mouse-1> <mouse-1> 
<down-mouse-1> <mouse-1> <down-mouse-1> <mouse-1> <down-mouse-1> 
<mouse-1> <down-mouse-1> <drag-mouse-1> <down-mouse-1> 
<mouse-movement> <drag-mouse-1> <down-mouse-1> <mouse-1> 
<wheel-down> <wheel-down> <down-mouse-1> <mouse-1> 
<down-mouse-1> <mouse-1> <down-mouse-1> <mouse-1> <wheel-down> 
<wheel-up> <down-mouse-1> <mouse-1> <down-mouse-1> 
<mouse-1> <down-mouse-1> <mouse-movement> <mouse-movement> 
<drag-mouse-1> <down-mouse-1> <mouse-1> C-c C-c <down-mouse-1> 
<mouse-1> <down-mouse-1> <mouse-1> C-a C-c @ C-c C-n 
C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n 
C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n 
C-n <S-down-mouse-1> <drag-mouse-1> <down-mouse-1> 
<mouse-movement> <drag-mouse-1> M-x s c s t <backspace> 
<backspace> SPC s t a <tab> <return> M-x r e p o r 
t SPC e m <tab> <return>

Recent messages:
Loading z:/siscog/sc-emacs/cl-hyperspec/online-doc.el (source)...
Loading z:/siscog/sc-emacs/cl-hyperspec/cltl2.el (source)...done
Loading z:/siscog/sc-emacs/cl-hyperspec/hyperspec.el (source)...
../../../../../sc-emacs/cl-hyperspec/hyperspec.el: `labels' is an obsolete 
macro (as of 24.3); use `cl-labels' instead.
Loading z:/siscog/sc-emacs/cl-hyperspec/hyperspec.el (source)...done
Loading z:/siscog/sc-emacs/cl-hyperspec/online-doc.el (source)...done
CREWS_DIR: z:/siscog/crews-vdev
Loading lisp-mode...done
Loading bytecomp...done
Loading z:/siscog/sc-emacs/init.el (source)...done

Load-path shadows:
z:/.emacs.d/el-get/ido-vertical-mode/ido-vertical-mode hides 
z:/holy/share/emacs/ido-vertical-mode
z:/siscog/sc-emacs/eli81/fi-manual hides z:/holy/share/emacs/fi-manual
z:/siscog/sc-emacs/cl-shell/completion hides 
z:/Vendor/emacs-24.4/share/emacs/24.4/lisp/completion

Features:
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text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote make-network-process
w32notify w32 multi-tty emacs)

Memory information:
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 (symbols 32 71291 49)
 (miscs 32 1592 2629)
 (strings 16 158464 16487)
 (string-bytes 1 4848736)
 (vectors 8 66501)
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