\barNumberCheck breaks \partcombine in 2.9.14

[Markus Schneider]

Hello all,

there's a bug in 2.9.14 (W2k):

\partcombine doesn't work anymore if a \barNumberCheck is used in any of the
two music expressions passed to it.

Error message:
------------------
Processing `partcombine_broken_2.9.14.ly'
Parsing...
Interpreting music...
Interpreting music... ERROR: In procedure =:
ERROR: Wrong type argument in position 1: ()
------------------

See example.

Markus


%%% Begin .ly snippet
%%% =================
\version "2.9.14"

musicI = \relative c' {
  c d e f
  g a b c
  \barNumberCheck #3 % if omitted, \partcombine will work as expected
  c, d e f
  g a b c
}

musicII = \relative c' {
  c d e f
  c d e f
  % \barNumberCheck #3
  c d e f
  c d e f
}

\score { {
  <<
    \partcombine \musicI \musicII
  >>
  }
  \layout {
    indent = 0
    ragged-right = ##t
  }
}
%%% ===============
%%% End .ly snippet