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

[Tom Tromey]

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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  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
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  savehist-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
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  column-number-mode: t
  line-number-mode: t
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Recent messages:
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Mark set
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previous-line: Beginning of buffer
funcall-interactively: End of buffer
Saving file /tmp/q.el...
Wrote /tmp/q.el

Load-path shadows:
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/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

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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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