bug#2680: 23.0.91; Tooltip persists inappropriately with tooltip-mode off

bug#2680: 23.0.91; Tooltip persists inappropriately with tooltip-mode off

[Bob Rogers]

   According to the tooltip-mode docstring:

	When Tooltip mode is disabled, Emacs displays one line of the
	help text in the echo area, and does not make a pop-up window.

Under certain circumstances, the full tooltip is redisplayed in the
message area after moving the mouse to a spot where no tooltip applies,
when it should be erased.

   To reproduce:

   1.  "emacs -Q"

   2.  "M-x tooltip-mode RET".  This is on by default, so it should
display "Tooltip mode disabled" in the message area.

   3.  Invoke "C-b" (or whatever) in order to clear the message area;
the bug manifests only if nothing is displayed there.

   4.  Move the mouse into the "-----" part of the right edge of the
mode line.  The message area will show the tooltip correctly, combined
into a single line and (if the frame is narrow enough) truncated at the
right.

   5.  Now move the mouse back into either the *scratch* buffer or the
message area.  The tooltip will still be displayed -- incorrectly, as it
no longer applies.  Furthermore, it won't be truncated; if the frame is
sufficiently narrow, the message area will grow in height to accomodate
the full message.

   6.  Moving the mouse out of the frame restores the message area.

   The attached patch to tooltip-show-help-non-mode appears to fix the
problem, though I suspect it is not TRT.  Shouldn't the third "cond"
clause in this function take care of this case?

					-- Bob Rogers
					   http://www.rgrjr.com/

------------------------------------------------------------------------
In GNU Emacs 23.0.91.1 (i686-pc-linux-gnu, GTK+ Version 2.12.9)
 of 2009-03-06 on rgr
Windowing system distributor `The X.Org Foundation', version 11.0.10400090
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: Emacs-Lisp

Minor modes in effect:
  diff-auto-refine-mode: t
  shell-dirtrack-mode: t
  mouse-wheel-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
  line-number-mode: t

Recent input:
C-SPC C-M-b M-w TAB C-SPC C-u C-SPC C-u C-n C-n C-n 
C-n M-f M-f SPC [ x ] C-c C-c C-n C-n C-n C-n C-p M-b 
M-d " " C-c C-c C-b [ y ] C-c C-c C-u C-p C-u C-p C-p 
C-M-f C-M-f C-M-b ( o r SPC C-M-f SPC " " ) C-c C-c 
C-b C-b [ ` <backspace> z ] C-e C-M-b C-M-f C-c C-c 
<help-echo> M-f M-f C-n C-M-f C-M-f C-x C-e <help-echo> 
C-u C-n M-b C-b C-b <backspace> <backspace> <backspace> 
<backspace> C-n C-n C-n C-b <backspace> <backspace> 
<backspace> C-f <backspace> <backspace> n i l C-e C-M-b 
C-M-f C-c C-c C-c C-c <help-echo> M-b <help-echo> C-u 
C-p C-u C-p M-b M-b M-b C-d C-d <backspace> C-e C-M-b 
C-M-f C-c C-c <help-echo> C-f <help-echo> M-b M-b M-b 
C-u C-u C-n C-u C-p C-p C-p C-p M-b M-b M-. <return> 
C-c b C-h f <return> M-, C-x o C-e M-b <return> C-v 
C-p C-p M-v C-s m e s s a g e ( C-r C-e C-f C-u C-SPC 
C-s m e s s a g e SPC ( C-r C-r C-s C-s C-s C-s C-s 
C-e C-f C-u C-SPC C-x C-b C-n C-n SPC C-u C-p C-p C-p 
C-p C-p C-p C-e C-b C-b C-b C-f <backspace> <backspace> 
<backspace> <backspace> C-M-b <M-backspace> <backspace> 
C-e C-M-b C-M-f C-c C-c <help-echo> C-f C-u C-n C-u 
C-n C-n M-b M-d " " C-c C-c <help-echo> C-b <help-echo> 
C-_ C-_ C-_ C-_ C-_ C-_ C-_ C-e C-M-b C-M-f ) C-c C-c 
<help-echo> C-f <help-echo> C-c C-c <help-echo> C-x 
h C-u C-SPC C-u C-SPC C-M-h M-w <help-echo> C-h c C-c 
C-c <help-echo> M-x e m a c - <backspace> s - b u <tab> 
g C-a C-k a p r SPC <return> C-y <return> M-x r e p 
o r <tab> <return>

Recent messages:
Done -- 510 definition lines.
Mark saved where search started [2 times]
tooltip-show-help-non-mode [2 times]
Auto-saving...
Undo! [7 times]
tooltip-show-help-non-mode [2 times]
Auto-saving...done
Mark set [4 times]
C-c C-c runs the command compile-defun
Auto-saving...done

[ATTACHMENT /usr/src/emacs/fix-tooltip-persistence.patch, text/plain]

bug#2680: 23.0.91; Tooltip persists inappropriately with tooltip-mode off

[Chong Yidong]

>    The attached patch to tooltip-show-help-non-mode appears to fix the
> problem, though I suspect it is not TRT.  Shouldn't the third "cond"
> clause in this function take care of this case?

I'm afraid the net monsters ate your attachment.  Could you resend it?
It's probably easiest to just put it in the body of your email.

bug#2680: 23.0.91; Tooltip persists inappropriately with tooltip-mode off

[Bob Rogers]

   From: Chong Yidong <cyd@stupidchicken.com>
   Date: Sun, 15 Mar 2009 21:44:56 -0400

   >    The attached patch to tooltip-show-help-non-mode appears to fix the
   > problem, though I suspect it is not TRT.  Shouldn't the third "cond"
   > clause in this function take care of this case?

   I'm afraid the net monsters ate your attachment.  Could you resend it?
   It's probably easiest to just put it in the body of your email.

Here it is.  (I was trying to distinguish the patch from the M-x
report-emacs-bug spew that came before it.  I guess I succeeded too
well.)

					-- Bob

------------------------------------------------------------------------
Index: lisp/tooltip.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/tooltip.el,v
retrieving revision 1.91
diff -u -r1.91 tooltip.el
--- lisp/tooltip.el	5 Jan 2009 03:19:50 -0000	1.91
+++ lisp/tooltip.el	15 Mar 2009 19:45:29 -0000
@@ -334,7 +334,7 @@
     (cond
      ((stringp help)
       (unless tooltip-previous-message
-        (setq tooltip-previous-message (current-message)))
+        (setq tooltip-previous-message (or (current-message) "")))
       (let ((message-truncate-lines t)
             (message-log-max nil))
         (message "%s" (replace-regexp-in-string "\n" ", " help))))