What to do with input/regression/page-spacing.ly

[Thomas Morley]

Hi,

in input/regression/page-spacing.ly several commands for
    \overrideProperty
    Score.NonMusicalPaperColumn.line-break-system-details
    ...
are applied, i.e. settings for Y-extent, refpoint-Y-extent,
next-padding, next-space, bottom-space.

As far as I can tell none of them has any visual effect anymore as
opposed to (far) earlier ly-version.
Attached a cut off from
http://lilypond.org/doc/v2.10/input/regression/collated-files.pdf
page 86
(In my pdf-viewer every glyph is omitted, incompatlible software for
such an old file I guess, but that's not the point here)
You'll see those settings _had_ an effect with v2.10
Additionally, the `obsolete-between-system-space` there let me guess
that convert-ly was applied to it at some point of time and since then
nobody touched it.

Strange enough, the last commit I've found tackling paper-system.scm is

commit 920dccaf627f00ec2d5bbd49ffeb9ad01236da3b
Author: Joe Neeman <address@hidden>
Date:   Fri Jun 9 02:20:21 2006 +0000

        * scm/paper-system.scm (paper-system-annotate): also annotate the
        estimated pure-Y-extent

        * scm/define-grobs.scm: add pure-Y-extent and pure-Y-offset functions

        * lily/system.cc (break_into_pieces): set the estimated height
        of each child system

        * lily/stem.cc (pure_height): new pure-Y-extent callback

        * lily/staff-symbol-referencer.cc (callback): don't destroy
        the staff-position property

        * lily/hara-kiri-group-spanner.cc (request_suicide): split
        consider_suicide into two functions

        * lily/constrained-breaking.cc (resize): use the new pure
        callbacks to estimate the height of a system

        * lily/axis-group-interface.cc (pure_group_height): new
        side-effect-free VerticalAxisGroup height-callback

        * lily/align-interface.cc (get_extents_aligned_translates):
        split align_elements_to_extents into two functions
        (get_pure_child_y_translation): new function

        * lily/grob.cc: new functions for pure-Y-extent and pure-Y-offset

        * lily/item.cc: new functions pure_is_visible and spanned_rank_iv

        * lily/paper-score.cc: cache break_indices and columns

        * lily/side-position-interface.cc: new pure-Y-extent callbacks

(maybe my search was not sufficient, though)

What happened with the possible settings for line-break-system-details and why?
What to do with this regtest?

Cheers,
  Harm

regtest-cut-off.pdf
Description: Adobe PDF document