Issue 2091 in lilypond: bug or feature with the extent of NoteColumn with 2.15.20

[lilypond]

Status: Accepted
Owner: ----
Labels: Type-Defect

New issue 2091 by address@hidden: bug or feature with the extent of  
NoteColumn with 2.15.20
http://code.google.com/p/lilypond/issues/detail?id=2091


Thomas Morley <thomasmorley65 <at> googlemail.com> sent an email

http://article.gmane.org/gmane.comp.gnu.lilypond.bugs/30626

reporting some unexpected behaviour as follows:

trying to compile a function manipulating the NoteColumn with "2.15.20" I
noticed some differences to "2.14.2"
So I wrote a test-function to display the grob-length:

\version "2.14.2"
%\version "2.15.20"

#(define (x-length-of-grob grob)
  (let* ((sys (ly:grob-system grob))
         (grob-length (interval-length (ly:grob-extent grob sys X))))
  (newline)
  (display grob-length)))

\relative c' {
        \override NoteColumn #'after-line-breaking = #x-length-of-grob
        <c e>4
        <c e>4.
        <c eis>4
        <c eis>4\arpeggio
}

With "2.14.2" I get:
1.316178
1.316178
1.316178
1.316178

With "2.15.20" I get:
1.316178
1.316178
1.316178
2.616182

It seems that in "2.15.20" the arpeggio is part of the NoteColumn. (But not
the DotColumn or the AccidentalPlacement)
The IR 3.2.71 note-column-interface states only stems and noteheads.
->
http://lilypond.org/doc/v2.15/Documentation/internals-big-page#note_002dcolumn_002dinterface

Is this a bug or a feature for something?

Cheers,
  Harm