Re: 23.0.60; scroll-up gives something between error and message

[Lennart Borgman (gmail)]

Stefan Monnier wrote:
> > There is something strange with the error handling in scroll-up. When
> > calling (scroll-up 1) in an empty buffer execution of the function calling
> > it stopped and a message is given. However there is no error generated.
>
> What makes you think no error is generated?


There is no traceback, but yes I did not try. Here is a try:

(defun test-scroll ()
  (interactive)
  (setq debug-on-error t)
  (let* ((buffer-name "test-scroll")
        (buffer (get-buffer buffer-name)))
    (when buffer (kill-buffer buffer))
    (setq buffer (get-buffer-create buffer-name))
    (switch-to-buffer buffer)
    (message "here 1") (sit-for 1)
    (condition-case err
        (scroll-up 1)
      (error (message "scroll-up error: %s" err)
             (sit-for 1)))
    (message "here 2") (sit-for 1)
    (scroll-up 1)
    (message "here 3") (sit-for 1)
    ))

The output is now

here 1
scroll-up error: (end-of-buffer)
here 2
let*: End of buffer

There is no *Backtrace* window shown for the second (scroll-up 1). Is 
there when you test it?