bug#57082: 29.0.50; emacs-news-view-mode breakage

[Stephen Berman <stephen.berman@gmx.net>]

On Tue, 09 Aug 2022 22:18:21 +0300 Juri Linkov <juri@linkov.net> wrote:

>>> The attached patch appears to fix the problems described above, but the
>>> only buffer using outline-minor-mode beside NEWS that I've tested it on
>>> is *Help* showing the output of describe-bindings, and the seems to work
>>> as expected with the patch (and due to the patch is not flagged as
>>> modified, though that isn't important for *Help*.)
>>
>> Thanks; patch applied to Emacs 29.

Thanks Lars.

> I noticed more problems: arrow directions are inverted - when an outline
> is hidden the arrow direction is open; when it's shown then the button has
> the closed state.

The arrows behave the same as in *Help* with describe-bindings:
outline-close (downward-pointing) when the body is hidden, outline-open
(leftward-pointing) when the body is shown.  Is that wrong?

> S-TAB (outline-cycle-buffer) is very slow: takes ~3 seconds on a small
> NEWS buffer.
>
> Also don't understand why is this change:
>
>          (when outline-minor-mode-highlight
> -          (if (and global-font-lock-mode (font-lock-specified-p major-mode))
> -              (progn
> -                (font-lock-add-keywords nil outline-font-lock-keywords t)
> -                (font-lock-flush))
> -            (outline-minor-mode-highlight-buffer)))
> +          (when (and global-font-lock-mode (font-lock-specified-p major-mode))
> +            (font-lock-add-keywords nil outline-font-lock-keywords t)
> +            (font-lock-flush))
> +          (outline-minor-mode-highlight-buffer))
>
> `outline-minor-mode-highlight-buffer' is intended only for buffers
> that don't support font-lock highlighting.

Yes, but with that change, arrows are displayed on first visiting the
NEWS buffer; without it, they only appear when typing TAB on an outline
heading.

>> The outline button stuff is still a work in progress, as you've found
>> out.  I'm not quite sure whether it should be switched on by default in
>> NEWS buffers -- it doesn't seem to bring much value there.  (As opposed
>> to in `describe-bindings', where it seems very helpful (since we're
>> starting out with some parts already folded.)
>
> It would be nicer if the color of the button depended on the outline's color,
> e.g. blue for the top-level blue outline face, etc.

I guess that would require using suitable images rather than emojis.

Steve Berman