bug#81462: [PATCH] Skip non-key events in `where-is-internal' with FIRSTONLY

Ping!  How can we make some further progress with this issue?

> Cc: [email protected], [email protected]
> Date: Mon, 27 Jul 2026 23:07:25 -0400
> From: Stefan Monnier via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <[email protected]>
> 
> >> Could you clarify why you think this is a bug?
> >> The doc says:
> >>
> >>     If FIRSTONLY is the symbol ‘non-ascii’, return the first binding
> >>     found, no matter what it is.
> >
> > At the end of the docstring for `where-is-internal', it says:
> >
> >     Keys that are represented as events that have a ‘non-key-event’ non-nil
> >     symbol property are ignored.
> 
> I see.  [ I don't think that addition was justified.  ]
> 
> > I figured that the intent was that such events in keymaps are not
> > really keys, cannot be invoked by users, and therefore should not be
> > listed by, e.g., where-is, describe-function, or
> > substitute-command-keys.  FWIW, shadowed key bindings are also skipped
> > even when FIRSTONLY is `non-ascii', so this seemed like an analogous
> > situation to me.
> 
> I'd argue they *can* be invoked by users, by causing the
> corresponding event.  I think it's not that different from the "events"
> used for menu entries.  Or the pseudo-events used for clicks on GUI
> elements like `mode-line`, `left-fringe`, ...
> 
> I think it's better to "demote" them (i.e. list them further down the
> list) rather than completely skip them.
> 
> >> BTW, I see that in bug#55940, Lars introduced the property `non-key-event`,
> >> but I'm not sure it's been fully thought through.  It seems wrong not to
> >> list them at all in `where-is-internal`.  I suspect it should be
> >> integrated into `preferred_sequence_p` instead.
> > The reason I was looking into this code at all was because I wanted to
> > tweak the behavior of where-is at my site.  Apologies in advance for
> > the verboseness below.
> 
> No apology needed, such background info is very welcome.
> 
> > Many of my site's users enable evil-mode, which happens to use some
> > non-key events for implementation reasons---see function
> > `evil-get-auxiliary-keymap'---and marking these synthetic events with
> > the `non-key-event' property might be a reasonable way to prevent
> > `substitute-command-keys' from returning them (albeit with some
> > additional patching here).
> >
> > As an example, from emacs -Q -L ~/src/evil-mode:
> >
> >   (evil-mode)
> >   (defun my-custom-command () (interactive))
> >   (keymap-global-set "C-x x z" #'my-custom-command) ;global key
> > binding for non-evil-mode users
> >   (evil-define-key 'normal lisp-interaction-mode-map
> >     (kbd "<f4>") #'my-custom-command)
> >   (evil-define-key 'insert lisp-interaction-mode-map
> >     (kbd "<f5>") #'my-custom-command)
> >
> > Now, invoking where-is or describe-function on my-custom-command
> > (assume you are in evil-normal-state) will tell you that the command
> > is bound to:
> >
> > my-custom-command is on <f4>, <normal-state> <f4>, <insert-state> <f5>, C-x x z
> >
> > Whereas the only key sequences you can actually type are <f4> and C-x
> > x z.  I would like to give the `normal-state' and `insert-state'
> > symbols a `non-key-event' property to prevent them from showing up in
> > this output at all.
> 
> Interesting.  This ties in with the recent discussion on emacs-devel
> about the "slow erosion of help's utility" for things like
> "metafunctions" (think `indent-for-tab-command`) and packages
> like Transient.
> 
> I'm thinking of adding what I think we should call "partial bindings"
> such that when a key lookup finds such a partial-binding it doesn't stop
> but keeps looking further and returns a "composite command" made up of
> all the partial bindings found (plus potentially a final non-partial
> binding), and partial bindings would have enough extra info to describe
> themselves (e.g. describe when they're active and when not).
> So `describe-function` could end up saying something like
> 
>     my-custom-command is on C-x x z, <f4> (in normal state), <f5>
>     (in insert state)
> 
> 
> === Stefan
> 
> 
> 
> 
>