Subject: bug#64713: 30.0.50; Modeline position not being updated while using mode-line-format-right-align

From: Juan Palacios <[email-masked]>
Date: Tue, 18 Jul 2023 18:15:27 +0200

mode-line-position does not get updated consistently when used in
combination with mode-line-format-right-align in mode-line-format.

Evaluate the following code in the *scratch* buffer, then C-n and C-p
and observe how the line counter on the mode line is not updated most
of the time:

(setq mode-line-format '("%e" mode-line-front-space
 (:propertize
  ("" mode-line-mule-info mode-line-client mode-line-modified
   mode-line-remote)
  display (min-width (5.0)))
 mode-line-frame-identification mode-line-buffer-identification "   "
 mode-line-position
 mode-line-format-right-align
 (vc-mode vc-mode) "  " mode-line-modes
 mode-line-misc-info mode-line-end-spaces))

Notice that mode-line-format-right-align was added just after
mode-line-position.

In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
 3.24.38, cairo version 1.17.8) of 2023-07-15 built on lilac-0
Repository revision: c5fa58cbc4a33a0a65494b9ab2e35d4f30ab849b
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101008
System Description: Arch Linux

Configured using:
 'configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
 --localstatedir=/var --mandir=/usr/share/man --with-gameuser=:games
 --with-modules --without-libotf --without-m17n-flt --without-gconf
 --with-native-compilation=yes --with-native-compilation=aot
 --with-sound=no --with-xwidgets --with-tree-sitter --without-gpm
 '--program-transform-name=s/\([ec]tags\)/\1.emacs/'
 'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions
 -Wp,-D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security
 -fstack-clash-protection -fcf-protection -g
 -ffile-prefix-map=/build/emacs-native-comp-git/src=/usr/src/debug/emacs-native-comp-git
 -flto=auto' 'LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now
 -flto=auto''

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LCMS2 LIBSYSTEMD LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY PDUMPER PNG
RSVG SECCOMP SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS TREE_SITTER WEBP
X11 XDBE XIM XINPUT2 XPM XWIDGETS GTK3 ZLIB

Important settings:
  value of $LANG: es_ES.utf8
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  show-paren-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
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr compile comint ansi-osc ansi-color ring comp
comp-cstr warnings icons rx cl-seq cl-macs gv cl-extra help-mode
bytecomp byte-compile emacsbug message mailcap yank-media puny dired
dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068
epg-config gnus-util text-property-search time-date subr-x mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
cl-loaddefs cl-lib sendmail rfc2047 rfc2045 ietf-drums mm-util
mail-prsvr mail-utils rmc iso-transl tooltip cconv eldoc paren electric
uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
term/x-win x-win term/common-win x-dnd tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer nadvice seq simple cl-generic
indonesian philippine 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
composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs
theme-loaddefs faces cus-face macroexp files window text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget keymap
hashtable-print-readable backquote threads xwidget-internal dbusbind
inotify lcms2 dynamic-setting system-font-setting font-render-setting
cairo gtk x-toolkit xinput2 x multi-tty move-toolbar
make-network-process native-compile emacs)

Memory information:
((conses 16 88483 19852) (symbols 48 7834 0) (strings 32 21667 1211)
 (string-bytes 1 676973) (vectors 16 16914)
 (vector-slots 8 344602 18303) (floats 8 27 63) (intervals 56 268 0)
 (buffers 984 11))