bug#35564: [PATCH v5] Tweak dired warning about "wildcard" characters

[Juri Linkov <juri@linkov.net>]

> Going over for bug#28969 and bug#35564, here are the
> discussion points I could identify:

It seems all these points are resolved now:

> - y-or-n-p propertizing its prompt rigidly: out of scope, since we use
>   read-multiple-choice now.

y-or-n-p doesn't propertize its prompt rigidly now, but indeed this is
out of scope when using read-char-from-minibuffer.

> - The prompt getting too long: it's now much shorter than the
>   four(!)-line version I came up with in v4; it concisely spells out the
>   issue (some characters will not be substituted) and invites the user
>   to ask for more details if needed.

Please use a shorter prompt like

  1 occurrence of ‘?’ will not be substituted.  Proceed? (y, n or ?) 

> - Asking the user whether they'd like to actually substitute these
>   characters: out of scope; not sure it's necessary, since the new
>   "details" buffer explains how to work around this for '?' (using
>   backquotes).

Displaying the new "Dired help" buffer on demand is a good idea.

> - Ensuring accessibility: users who cannot distinguish the 'warning'
>   face are now invited to add optional '^' markers.

In the new "Dired help" buffer where there is enough space to add
the command line with '^' markers.

> - Preventing '`' being linked to the backquote macro in the docstring
>   for dired-do-shell-command: still no idea how to fix that, but that
>   can be investigated independently.

Maybe use double quotes "`" as an exception.

> Here are some remaining issues I can think of:
>
> - The code that toggles the '^' markers does not check that the command
>   is not wrapped/truncated (i.e. that the window is wide enough).

Everything should be explained in the new "Dired help" buffer
including the command line with '^' markers.

> - The details window might not be tall enough, in which case maybe I
>   should add [f]orward-/[b]ackward-page actions like nsm.el does.

Yesterday I added new keybindings C-v/M-v for scrolling the original
window from the minibuffer.

> - In dired--no-subst-confirm, I did my best to make the window-popping
>   dance as graceful as possible (unwind-protect so that the details
>   buffer is killed even after C-g, save-window-excursion to restore the
>   window configuration…), but maybe it falls apart in cases I haven't
>   considered.

Maybe some of the standard display-window functions can handle this,
but this is a minor question.

> - UI bikeshedding: maybe drop the leading "Warning:"

Right, this makes the prompt shorter.