Subject: bug#75931: 31.0.50; mouse-face and pointer properties make pointer change back and forth

From: Mauro Aranda <[email-masked]>
Date: Wed, 29 Jan 2025 15:22:41 -0300

After emacs -Q, evaluate this:

(defun my-test ()
   (interactive)
   (switch-to-buffer "*Test*")
   (kill-all-local-variables)
   (make-local-variable 'widget-example-repeat)
   (let ((inhibit-read-only t))
     (erase-buffer))
   (remove-overlays)
   (insert "TEST")
   (let ((ov (make-overlay (point-min) (point-max))))
     (overlay-put ov 'pointer 'hand))
   (let ((ov (make-overlay (point-min) (point-max))))
     (overlay-put ov 'pointer 'arrow)
     (overlay-put ov 'mouse-face 'shadow)
     (overlay-put ov 'priority 110))
   (insert "\nText without overlay"))

M-x my-test RET

Hover with the mouse the text "TEST", and move point to it (for example,
with M-<).  The pointer begins to change back and forth between arrow
and hand, staying as arrow most of the time.

This seems to be toolkit-dependant, since it doesn't happen on
MS-Windows:
https://lists.gnu.org/archive/html/emacs-devel/2025-01/msg01116.html

In GNU Emacs 31.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
  3.24.33, cairo version 1.16.0) of 2025-01-29 built on tbb-desktop
Repository revision: 142fe5ace4e5d4ed667505f73fc95757a764d530
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12201001
System Description: Ubuntu 22.04.5 LTS

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG
LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 M17N_FLT MODULES NOTIFY
INOTIFY PDUMPER PNG RSVG SECCOMP SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS TREE_SITTER X11 XDBE XIM XINPUT2 XPM GTK3 ZLIB

Important settings:
   value of $LC_MONETARY: es_AR.UTF-8
   value of $LC_NUMERIC: es_AR.UTF-8
   value of $LC_TIME: es_AR.UTF-8
   value of $LANG: en_US.UTF-8
   value of $XMODIFIERS: @im=ibus
   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
   minibuffer-regexp-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 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 touch-screen 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 dbusbind inotify lcms2
dynamic-setting system-font-setting font-render-setting cairo gtk
x-toolkit xinput2 x multi-tty move-toolbar make-network-process
tty-child-frames emacs)

Memory information:
((conses 16 38994 10422) (symbols 48 5406 0) (strings 32 12571 1813)
  (string-bytes 1 303272) (vectors 16 9355)
  (vector-slots 8 112629 8058) (floats 8 21 3) (intervals 56 233 0)
  (buffers 992 10))