Excessive highlighting of overlay with display property

[Ralf Angeli]

Copying

(let (ov)
  (insert "\n\nxxx")
  (setq ov (make-overlay (line-beginning-position) (point)))
  (overlay-put ov 'mouse-face 'highlight)
  (overlay-put ov 'display "yyy"))

into the *scratch* buffer and typing `C-x C-e' with point at the last
parenthesis, you will see the string "yyy" further below.  If you
hover with the mouse pointer over it, not only the string will be
highlighted (which is what I expected) but also the line above the
string.

(I don't know if this is related, but some time ago I reported a bug
concerning partial highlighting of a wrapped overlay (see
<URL:http://article.gmane.org/gmane.emacs.pretest.bugs:4225>).
According to src/ChangeLog I think it was fixed on 2005-01-18.  Maybe
the fix has something to do with it?)


In GNU Emacs 22.0.50.1 (i686-pc-linux-gnu, GTK+ Version 2.6.2)
 of 2005-02-19 on neutrino
Distributor `The XFree86 Project, Inc', version 11.0.40300001
configured using `configure '--with-gtk''

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
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  display-time-mode: t
  iswitchb-mode: t
  show-paren-mode: t
  encoded-kbd-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
i o n ) <right> <right> <right> <right> <C-backspace> 
( p o i n t ) <down> <down> C-x C-e q C-_ <down> <down> 
<down> <up> <left> <left> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> " " <left> y y 
y <right> <right> <right> C-x C-e C-: C-_ <up> <up> 
<up> <left> <left> <left> <left> <left> \ n <down> 
<down> <down> <down> <down> <down> <left> C-x C-e C-_ 
<right> <up> <return> <return> <return> <up> <up> <up> 
<left> ) C-x C-e C-_ C-_ C-_ C-_ C-_ <down> <left> 
<right> <down> M-x r e p o r t - e m <tab> <return
>

Recent messages:
Entering debugger...
Back to top level.
Undo!
"yyy"
Undo!
"yyy"
Undo!
highlight
Undo! [5 times]
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