bug#16870: 24.3; "display" text property versus ":box" face attribute

bug#16870: 24.3; "display" text property versus ":box" face attribute

[Ben Liblit]

If a range of text carries the "display" text property and also has its 
"face" text property set to something with the ":box" attribute, then 
the right edge of the box is not actually drawn.  The following elisp 
code fragment demonstrates the problem:

     (let ((buffer (generate-new-buffer "*bug*")))
       (set-buffer buffer)
       (insert "lorem ipsum dolor\n\nlorem ipsum dolor\n")
       (put-text-property 7 12 'display "xxxxx")
       (put-text-property 7 12 'face '(:box t))
       (put-text-property 26 31 'face '(:box t))
       (switch-to-buffer-other-window buffer))

Observe that on the first line, the displayed "xxxxx" replacement text 
has only three box edges drawn: top, left, and bottom.  The right edge 
is missing.  By contrast, the second line of text has no "display" text 
property set and shows a proper box with all four edges.


In GNU Emacs 24.3.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.18.9)
  of 2013-06-10 on mcgee.cs.wisc.edu
Windowing system distributor `Red Hat, Inc.', version 11.0.11300000
System Description:	Red Hat Enterprise Linux Server release 6.5 (Santiago)

Configured using:
  `configure '--prefix=/unsup/emacs-24.3/amd64_rhel6' '--without-pop'
  '--without-sound' '--with-gif=no''

Important settings:
   value of $LC_CTYPE: en_US.UTF-8
   value of $LANG: en_US.UTF-8
   value of $XMODIFIERS: @im=none
   locale-coding-system: utf-8-unix
   default enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
   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
   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:
C-y C-x C-e <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.
Mark set
#<buffer *bug*>

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 time-date tooltip ediff-hook vc-hooks
lisp-float-type mwheel x-win x-dnd 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 loaddefs button faces
cus-face macroexp files text-properties overlay sha1 md5 base64 format
env code-pages mule custom widget hashtable-print-readable backquote
make-network-process dbusbind dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty emacs)

bug#16870: 24.3; "display" text property versus ":box" face attribute

[Eli Zaretskii]

> Date: Mon, 24 Feb 2014 15:18:07 -0600
> From: Ben Liblit <liblit@acm.org>
> 
> If a range of text carries the "display" text property and also has its 
> "face" text property set to something with the ":box" attribute, then 
> the right edge of the box is not actually drawn.  The following elisp 
> code fragment demonstrates the problem:
> 
>      (let ((buffer (generate-new-buffer "*bug*")))
>        (set-buffer buffer)
>        (insert "lorem ipsum dolor\n\nlorem ipsum dolor\n")
>        (put-text-property 7 12 'display "xxxxx")
>        (put-text-property 7 12 'face '(:box t))
>        (put-text-property 26 31 'face '(:box t))
>        (switch-to-buffer-other-window buffer))
> 
> Observe that on the first line, the displayed "xxxxx" replacement text 
> has only three box edges drawn: top, left, and bottom.  The right edge 
> is missing.  By contrast, the second line of text has no "display" text 
> property set and shows a proper box with all four edges.

Thanks, I fixed this in trunk revision 116585.

For the record: this bug was there since Emacs 21.1, when the 'box'
face was first introduced.

bug#16870: closed (Re: bug#16870: 24.3; "display" text property versus ":box" face attribute)

[Ben Liblit]

Excellent.  Thanks for the speedy fix!