Re: two related edebug problems

[Chong Yidong <cyd@stupidchicken.com>]

"Ken Manheimer" <ken.manheimer@gmail.com> writes:

> i am able to reliably reproduce the first problem (always single
> stepping).  i open a new emacs session with emacs -Q, find the
> standard `newline' function (in simple.el - i just use
> `find-function'), edebug-defun it, then do a newline in the scratch
> buffer.  if i just use "f" to step through, it almost immediately goes
> into the always-single-step mode - after `(barf-if-buffer-read-only)'.
> "c", "o", "f", "h", all work like hitting the space bar.

This seems to be triggered by the following code in edebug-display:

	  (if (edebug-input-pending-p)
	      (progn
		(setq edebug-execution-mode 'step
		      edebug-stop t)
		(edebug-stop)
		;;	    (discard-input)		; is this unfriendly??
		))

Commenting this out removes the problem, but this is probably not what
we want.  My guess is that input-pending-p is returning spuriously (it
does not guarantee that there is really input pending).

One possibility is to make use of the sit-for statements further down
in edebug-display.  Since sit-for now returns iff there is real input,
we could capture the return value and use that to determine whether to
stop execution.