On Sat, Jun 18, 2016 at 1:42 PM, Eli Zaretskii <eliz@gnu.org> wrote:

I see that you consider this a regression. But the change you refer
to was in Emacs 22.1, released 9 years ago, so we've lived with this
long enough to consider your proposal a new feature.

Well, we just fixed a 20-year-old documentation bug on markers from some prior discussion, but I see why you might want to view it that way. If the behavior is a bug, no matter how long-standing, it should certainly be given some standing above a regular new feature request. Maybe RMS could comment on whether sort-lines by design should sort only visible lines, e.g. when some are hidden in outlines, or should sort all lines regardless of visibility.

I also think
that your proposed change goes farther than just restoring that old
behavior, because outline and its derivatives are not the only modes
that use invisible text.

Can you provide one example where this patch changes the behavior of line sorting in a negative way? That would help to understand your thinking. I have provided the example of where it improves it.

This should be simple to resolve by just getting to the bottom of what the function is designed to do in the case of invisible lines.

Bob