Broken TextSpanner does affect horizontal spacing

[David Nalesnik]

In the following snippet, horizontal spacing is not stretched to fit the
broken spanner with long text on its second line.

It may be that proper accommodation requires at least one bound of
TextSpanner to be set to NoteColumn.  In the snippet, one of the bounds of
the sibling on either the first or third line is set to NoteColumn, while
the sibling on the middle line is bounded on left and right by
NonMusicalPaperColumn.

(The snippet outputs the bound information.)

#(define (display-bounds grob)
   (format #t "spanner: ~a LEFT: ~a RIGHT: ~a~%"
     grob
     (ly:spanner-bound grob LEFT)
     (ly:spanner-bound grob RIGHT)))

\score {
  \relative c' {
    \override TextSpanner.after-line-breaking = #display-bounds
    \override TextSpanner.minimum-length = #50
    \override TextSpanner.springs-and-rods = #ly:spanner::set-spacing-rods
    \override TextSpanner.bound-details.left.text =
    \markup { \upright "an excessively long text indication" }
    a4 \startTextSpan c d e
    \break
    a4 b c d
    \break
    a b c d\stopTextSpan
  }
  \layout {
    ragged-right = ##t
  }
}

text-spanner-bug.png
Description: PNG image