bug#54684: 28.0.92; tab-undo doesn't respect numeric tab-bar-show

bug#54684: 28.0.92; tab-undo doesn't respect numeric tab-bar-show

[Knut Anders Hatlen]

(setq tab-bar-show 1)
(tab-new)
(tab-close)
(tab-undo)

The expected result of this sequence of commands is to have two tabs,
and the tab bar is shown because the number of tabs is higher than the
value of tab-bar-show. The actual result is that there are two tabs, but
the tab bar is not shown. (If a third tab is created, the tab bar
reappears.)


In GNU Emacs 28.0.92 (build 3, x86_64-pc-linux-gnu, GTK+ Version 3.24.33, cairo version 1.16.0)
 of 2022-04-02 built on dell
Repository revision: 9b5e9715ea64f971e215e91898e3ef49b159cdbe
Repository branch: emacs-28
System Description: Debian GNU/Linux bookworm/sid

Configured using:
 'configure --with-native-compilation --with-json --with-xml2
 --with-modules 'CFLAGS=-O2 -flto -march=native' LDFLAGS=-flto
 --prefix=/usr/local/stow/emacs'

Configured features:
CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LCMS2 LIBOTF LIBSELINUX LIBXML2 M17N_FLT MODULES NATIVE_COMP NOTIFY
INOTIFY PDUMPER PNG RSVG SECCOMP SOUND THREADS TIFF TOOLKIT_SCROLL_BARS
X11 XDBE XIM XPM GTK3 ZLIB

Important settings:
  value of $LANG: nn_NO.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Outline

Minor modes in effect:
  bug-reference-mode: t
  tooltip-mode: t
  global-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
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t
  view-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug comp comp-cstr warnings rx message rmc
puny dired dired-loaddefs rfc822 mml mml-sec epa derived epg rfc6068
epg-config gnus-util rmail rmail-loaddefs auth-source cl-seq eieio
eieio-core cl-macs eieio-loaddefs password-cache json map time-date
subr-x mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util
mail-prsvr mail-utils shortdoc text-property-search cl-extra cl-print
misearch multi-isearch vc-git diff-mode vc-dispatcher bug-reference seq
noutline outline easy-mmode view thingatpt help-fns radix-tree help-mode
cl-loaddefs cl-lib term/xterm xterm byte-opt gv bytecomp byte-compile
cconv iso-transl tooltip 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 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 composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice button
loaddefs faces cus-face macroexp files window text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote threads dbusbind inotify lcms2
dynamic-setting system-font-setting font-render-setting cairo
move-toolbar gtk x-toolkit x multi-tty make-network-process
native-compile emacs)

Memory information:
((conses 16 118140 10397)
 (symbols 48 8927 1)
 (strings 32 28029 1855)
 (string-bytes 1 888628)
 (vectors 16 17393)
 (vector-slots 8 321422 13305)
 (floats 8 77 112)
 (intervals 56 353 0)
 (buffers 992 15))

-- 
Knut Anders

bug#54684: 28.0.92; tab-undo doesn't respect numeric tab-bar-show

[Juri Linkov]

close 54684 29.0.50
thanks

> (setq tab-bar-show 1)
> (tab-new)
> (tab-close)
> (tab-undo)
>
> The expected result of this sequence of commands is to have two tabs,
> and the tab bar is shown because the number of tabs is higher than the
> value of tab-bar-show. The actual result is that there are two tabs, but
> the tab bar is not shown. (If a third tab is created, the tab bar
> reappears.)

Thanks for showing the valid use case.  This is fixed now in Emacs 29.