bug#12204: 24.1.50; Binding mouse-movement interferes with "C-h c" for mouse clicks

[Eli Zaretskii]

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgment at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from `emacs -Q':

    emacs -Q
    M-x gdb RET

 . Choose some executable, it doesn't matter which one, and type its file
   name followed by RET.

 . Wait for GDB to start up and show its prompt, then type:

    M-x gud-tooltip-mode RET

 . If your Emacs bzr revision is older than 109615, click the mouse
   once somewhere in the window.  (Revision 109615 fixed the bug which
   required that click.)

 . Type "C-h c", and then move the mouse to some tool-bar button or
   menu-bar menu item, and click on it.  Watch in disbelief as Emacs
   _executes_ the command bound to that click instead of showing its
   documentation.

 . Repeat the experiment, but this time, after "C-h c" slowly move the
   mouse a small ways and watch the echo area.  You will see a message
   there:

     <mouse-movement> runs the command gud-tooltip-mouse-motion

   The message will disappear after you move the mouse again.

This happens because gud-tooltip-mode binds the command
gud-tooltip-mouse-motion to mouse-movement event.  The echo area
display of "C-h c" about that is promptly erased by the next mouse
motion, so if you are going for a tool bar or menu bar, you won't
notice it.  Then you will be surprised by the execution of a command
for which you wanted to see help.

This is not a bug, strictly speaking: the help command works as
designed.  But I wonder whether we could somehow surprise the user
less in this situation.

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
d:/gnu/bzr/emacs/trunk/etc/DEBUG.


In GNU Emacs 24.1.50.1 (i386-mingw-nt5.1.2600)
 of 2012-08-14 on HOME-C4E4A596F7
Bzr revision: 109616 eliz@gnu.org-20120814184839-4s25r2c06hsuazco
Windowing system distributor `Microsoft Corp.', version 5.1.2600
Configured using:
 `configure --with-gcc (3.4) --no-opt --enable-checking --cflags
 -Id:/usr/include/libxml2 -DGLYPH_DEBUG=1'

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1255
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  gud-tooltip-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-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x g d b <return> <M-backspace> <M-backspace> . . 
/ s r <tab> o <tab> / i <tab> e m a c s SPC <backspace> 
. e x e <return> M-x g u d - g d b <tab> <backspace> 
<backspace> <backspace> t o o l <tab> m o d e <return> 
<mouse-movement> C-h c <mouse-movement> C-h c <mouse-movement> 
<mouse-movement> <help-echo> <help-echo> <mouse-movement> 
<menu-bar> <buffer> C-@ <help-echo> <mouse-movement> 
<help-echo> <mouse-movement> <mouse-movement> <mouse-movement> 
C-h c <mouse-movement> <mouse-movement> <mouse-movement> 
<help-echo> <menu-bar> <buffer> C-a <help-echo> M-x 
r e p o r t - e m <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Target doesn't support non-stop mode.  Turning it off.
Gud-Tooltip mode enabled
<mouse-movement> runs the command gud-tooltip-mouse-motion [3 times]

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
easymenu mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils cus-start cus-load gdb-mi bindat json gud
easy-mmode comint ansi-color ring time-date tooltip ediff-hook vc-hooks
lisp-float-type mwheel dos-w32 disp-table ls-lisp w32-win w32-vars
tool-bar dnd fontset image regexp-opt fringe tabulated-list newcomment
lisp-mode register page menu-bar rfn-eshadow timer select scroll-bar
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
minibuffer button faces cus-face files text-properties overlay sha1 md5
base64 format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process multi-tty emacs)