bug#35393: 26.2; `help-echo' text propertized with `face' is not shown in that face

bug#35393: 26.2; `help-echo' text propertized with `face' is not shown in that face

[Drew Adams]

emacs -Q
C-x b foo ; buffer in fundamental mode

Type a line of arbitrary text.

Type this and evaluate it:

  (put-text-property 1 10 'help-echo "ABCDEFG")

No problem. The tooltip appears as expected, using face `tooltip'.

Now try this instead:

(put-text-property 1 10
  'help-echo (propertize "rstuvwxyz" 'face 'custom-changed))

The propertized string is not used.  The text property `face' is set
correctly, but the tooltip displayed ignores it.

If this is not considered a bug then please consider it an enhancement
request to be able to use a propertized string.

Consider the use case of a tooltip that shows a tiny bit of code, but
with more than one line, so that alignment etc. is important.  You might
well want that code to be shown in a fixed-width font.  You should be
able to do this by passing a string propertized with the appropriate
face.


In GNU Emacs 26.2 (build 1, x86_64-w64-mingw32)
 of 2019-04-13
Repository revision: fd1b34bfba8f3f6298df47c8e10b61530426f749
Windowing system distributor `Microsoft Corp.', version 10.0.17134
Configured using:
 `configure --without-dbus --host=x86_64-w64-mingw32
 --without-compress-install 'CFLAGS=-O2 -static -g3''

bug#35393: 26.2; `help-echo' text propertized with `face' is not shown in that face

[Drew Adams]

Forgot to add:

Contrast this with `x-show-tip', which accepts a propertized string and shows the tooltip using it.

Why should tooltip use of `help-echo' override or
ignore any text properties on its string value?

bug#35393: 26.2; `help-echo' text propertized with `face' is not shown in that face

[Lars Ingebrigtsen]

Drew Adams <drew.adams@oracle.com> writes:

> Now try this instead:
>
> (put-text-property 1 10
>   'help-echo (propertize "rstuvwxyz" 'face 'custom-changed))
>
> The propertized string is not used.  The text property `face' is set
> correctly, but the tooltip displayed ignores it.

So the test case here is basically:

(tooltip-show (propertize "foo" 'face 'error))

This was apparently fixed earlier this year in Emacs 28.  The code is
now:

          ;; Use non-nil APPEND argument below to avoid overriding any
          ;; faces used in our TEXT.  Among other things, this allows
          ;; tooltips to use the `help-key-binding' face used in
          ;; `substitute-command-keys' substitutions.
          (add-face-text-property 0 (length text) 'variable-pitch t text)

So I'm closing this bug report.  If this is still a problem (there's
some difference between different architectures), please respond to the
debbugs address and we'll reopen.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no