bug#31692: Emacs sometimes drops key events

[Michael Heerdegen]

Eli Zaretskii <eliz@gnu.org> writes:

> My reading of the documentation of while-no-input is that yes, this
> is the expected behavior.  The description in the ELisp manual is
> especially explicit about "quit-like" effect of early arrival of
> input.

AFAIU, this quit-like effect should be limited to `while-no-input' and
not be propagated to top-level.  I also read the documentation of the
low-level tools with which this is implemented - `throw-input' and
`quit-flag', and that also gives me the impression that generating a
"quit" signal is not intended (that would also be not very useful).  We
only want a quit to come through when the user really quits (C-g) -
that's while `while-no-input' (which uses `with-local-quit' that sets
`quit-flag') explicitly quit - but only when a quit had been
intercepted.

I made some further experiments with my test function

#+begin_src emacs-lisp
(defun test ()
  (interactive)
  (while-no-input
    (sit-for 3))
  (message "Done"))
#+end_src

What I found was that when I load the source file subr.el, or only the
definition of `sit-for', calling `test' and hitting a key does not
produce a quit any more.  Something here seems not kosher.


Michael.