Re: linum.el: problem (bug ?) fix and improvement

[Eli Zaretskii]

> From: Stefan Monnier <address@hidden>
> Date: Thu, 12 May 2011 10:58:58 -0300
> Cc: address@hidden
> 
> What we'd like here is for the redisplay to ignore the margin property
> placed on invisible text.

Are you sure?  Only part of a line could be invisible, in which case
it won't be easy to explain why we drop the before-string on the
floor.  I would be uneasy to make such radical changes on behalf of a
single use case.

> This boils down to making Emacs ignore
> `before-string' properties placed at the beginning of invisible text.
> I don't think it's always right to ignore them, tho.

There's explicit code to do it the way we do now:

          /* If there are before-strings at the start of invisible
             text, and the text is invisible because of a text
             property, arrange to show before-strings because 20.x did
             it that way.  (If the text is invisible because of an
             overlay property instead of a text property, this is
             already handled in the overlay code.)  */
          if (NILP (overlay)
              && get_overlay_strings (it, it->stop_charpos))
            {
              handled = HANDLED_RECOMPUTE_PROPS;
              it->stack[it->sp - 1].display_ellipsis_p = display_ellipsis_p;
            }

Just undoing this would be regression from Emacs 20.x.