bug#26012: 25.2; help-echo should show in echo area when point is in text

[Tom Tromey <tom@tromey.com>]

Make sure you have font-lock enabled, open a new .el file and insert:

'(("^[ \t]*\\(?:\\* .*\\)?\\(([^\n)]*,\\s-*\\)$"
   (1 '(face font-lock-warning-face
	     help-echo "Continue function lists with \")\\n(\".") t))

(This snippet comes from log-edit.el)

For me the final "t))" is given font-lock-warning-face.
It also has this text property:

  help-echo            "Hidden behind deeper element; move to another line?"

... which is very useful information!

However, the only way I can see this (other than describe-char) is to
hover over the highlighted text with the mouse.

I think it would be handier if this text were displayed somewhere when
point was in this area.  Some other error-displaying programs, like
flycheck (I didn't look at flymake) will do this already; I just think
it should be standard across Emacs.

Tom




In GNU Emacs 25.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.22.8)
 of 2017-03-02 built on bapiya
Repository revision: 6e788ef0e262fafc014c21f4ad52cc5dc9f1715b
Windowing system distributor 'Fedora Project', version 11.0.11901000
System Description:	Fedora release 25 (Twenty Five)

Configured using:
 'configure --prefix=/home/tromey/Emacs/install/ --with-modules'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND GPM DBUS GCONF GSETTINGS
NOTIFY LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 MODULES

Important settings:
  value of $LANG: en_US.utf8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Group

Minor modes in effect:
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  gnus-topic-mode: t
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  shell-dirtrack-mode: t
  diff-auto-refine-mode: t
  which-function-mode: t
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  erc-networks-mode: t
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  erc-track-mode: t
  erc-match-mode: t
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  erc-hl-nicks-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  savehist-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
nnimap read 0k from mail.tromey.com
No more unseen articles
Expiring articles...done
Mark set
(New file)
Mark set
previous-line: Beginning of buffer
funcall-interactively: End of buffer
Saving file /tmp/q.el...
Wrote /tmp/q.el

Load-path shadows:
/home/tromey/.emacs.d/elpa/bubbles-0.5/bubbles hides /home/tromey/Emacs/install/share/emacs/25.2/lisp/play/bubbles
/home/tromey/.emacs.d/elpa/soap-client-3.1.1/soap-inspect hides /home/tromey/Emacs/install/share/emacs/25.2/lisp/net/soap-inspect
/home/tromey/.emacs.d/elpa/soap-client-3.1.1/soap-client hides /home/tromey/Emacs/install/share/emacs/25.2/lisp/net/soap-client

Features:
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log-view bbdb-sc supercite regi org-bullets org-element org-rmail
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org-pcomplete org-list org-faces org-entities noutline outline
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org-src ob-keys ob-comint ob-core ob-eval org-compat org-macs
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appt diary-lib diary-loaddefs cal-menu calendar cal-loaddefs which-func
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erc-pcomplete pcomplete erc-track erc-match erc-netsplit erc-hl-nicks
color erc-button erc-fill erc-stamp wid-edit erc-goodies erc erc-backend
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finder-inf dwarf-mode-autoloads gdb-shell-autoloads eieio-core
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weblogger-autoloads info package epg-config seq byte-opt gv bytecomp
byte-compile cl-extra help-mode easymenu cconv cl-loaddefs pcase cl-lib
bbdb-loaddefs time-date mule-util tooltip eldoc electric uniquify
ediff-hook vc-hooks lisp-float-type mwheel x-win term/common-win x-dnd
tool-bar dnd fontset image regexp-opt fringe tabulated-list newcomment
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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 dbusbind inotify
dynamic-setting system-font-setting font-render-setting move-toolbar gtk
x-toolkit x multi-tty make-network-process emacs)

Memory information:
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 (symbols 48 130591 50)
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 (vectors 16 100488)
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