bug#25855: 25.1; garbage display by raise display specification

bug#25855: 25.1; garbage display by raise display specification

[ynyaaa]

Evaluating the form below, emacs displays garbages at the leftside of
the window. Switching to another buffer and switching back will display
other garbages.

(insert (propertize (make-string 100 ?\n) 'display '(raise 1)))



In GNU Emacs 25.1.1 (i686-w64-mingw32)
 of 2016-09-18 built on LAPHROAIG
Windowing system distributor 'Microsoft Corp.', version 6.0.6002
Configured using:
 'configure --host=i686-w64-mingw32 --without-dbus
 --without-compress-install CFLAGS=-static'

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB
TOOLKIT_SCROLL_BARS

Important settings:
  value of $LANG: JPN
  locale-coding-system: cp932

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-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 messages:

Load-path shadows:
None found.

Features:
(network-stream nsm starttls tls gnutls mailalias smtpmail auth-source
cl-seq eieio byte-opt bytecomp byte-compile cl-extra cconv eieio-core
cl-macs gv misearch multi-isearch pp shadow sort mail-extr emacsbug
message dired format-spec rfc822 mml mml-sec password-cache epg
epg-config gnus-util mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums
mm-util help-fns help-mode easymenu cl-loaddefs pcase cl-lib mail-prsvr
mail-utils time-date mule-util japan-util tooltip eldoc electric
uniquify ediff-hook vc-hooks lisp-float-type mwheel dos-w32 ls-lisp
disp-table w32-win w32-vars term/common-win tool-bar dnd fontset image
regexp-opt fringe tabulated-list newcomment elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow timer select scroll-bar
mouse jit-lock font-lock syntax facemenu font-core frame cl-generic cham
georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese charscript case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer cl-preloaded nadvice
loaddefs button faces cus-face macroexp files text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote w32notify w32 multi-tty
make-network-process emacs)

Memory information:
((conses 8 106168 12671)
 (symbols 32 21061 0)
 (miscs 32 78 212)
 (strings 16 20017 4805)
 (string-bytes 1 568678)
 (vectors 8 15193)
 (vector-slots 4 543326 7314)
 (floats 8 204 315)
 (intervals 28 595 15)
 (buffers 520 23))

bug#25855: 25.1; garbage display by raise display specification

[Eli Zaretskii]

> From: ynyaaa@gmail.com
> Date: Fri, 24 Feb 2017 15:09:43 +0900
> 
> Evaluating the form below, emacs displays garbages at the leftside of
> the window. Switching to another buffer and switching back will display
> other garbages.
> 
> (insert (propertize (make-string 100 ?\n) 'display '(raise 1)))

What did you expect to see from 'raising' the newlines?  A newline has
no glyph on display, so there's nothing to raise.

IOW, why is this not the expected behavior?

bug#25855: 25.1; garbage display by raise display specification

[ynyaaa]

Eli Zaretskii <eliz@gnu.org> writes:
>> (insert (propertize (make-string 100 ?\n) 'display '(raise 1)))
>
> What did you expect to see from 'raising' the newlines?  A newline has
> no glyph on display, so there's nothing to raise.
>
> IOW, why is this not the expected behavior?

I found that it is sufficient to put display property at the last
character of a buffer.
Evaluating the form below, leftmost digits remain to be displayed.

(progn
  (switch-to-buffer (generate-new-buffer "temp"))
  (dotimes (i 100) (insert (format "%d\n" i)))
  (goto-char (point-min))
  (redisplay)
  (erase-buffer)
  (insert (propertize "X" 'display '(raise 1))))

bug#25855: 25.1; garbage display by raise display specification

[Eli Zaretskii]

> From: ynyaaa@gmail.com
> Cc: 25855@debbugs.gnu.org
> Date: Sat, 25 Feb 2017 00:36:15 +0900
> 
> Evaluating the form below, leftmost digits remain to be displayed.
> 
> (progn
>   (switch-to-buffer (generate-new-buffer "temp"))
>   (dotimes (i 100) (insert (format "%d\n" i)))
>   (goto-char (point-min))
>   (redisplay)
>   (erase-buffer)
>   (insert (propertize "X" 'display '(raise 1))))

Thanks, fixed.