bug#3576: 23.0.94; scroll bar scrolls past eob - keeps scrolling

[Drew Adams]

> > emacs -Q
> > C-x C-f /path/to/allout.el
> > C-x 1
> > Scroll down using mouse on scroll-bar slider. You can 
> > scroll so that no text is visible, all text is above the
> > (single) window. Same thing even if there are
> > other windows above or below.
> 
> Yep.  Emacs 21.4 stops on the last text line, Emacs 22.3 and 23.0.94
> stop on EOB.

What do you mean by "stop on EOB"? If end of the buffer is the newline
immediately following the last line of non-newline chars, then how can showing
up to a screenful of blank vertical space be considered "stopping at EOB"?

Do you mean that it decides that the final newline has as a right to be scrolled
to the top of the screen? Is that what "stopping at eob" means?

If this is just an unfortunate result of the way things happen to be currently
implemented, that's one thing. But I find it hard to believe that this would
have been a design goal - that someone would start out intentionally to produce
this behavior. What's the advantage or use case?

I've never seen this behavior in any other app (though I'm sure you'll come up
with some other app that has the same behavior). ;-)