Completion notes

[Thies Albrecht]

Hi everybody!

For the first I'm typesetting a score containing 'completion notes'. I 
don't know if that's the correct name for it, but I found something 
similar in the regression tests.

What I mean with 'completion' is:
There is a dotted half note starting in  bar#1 on beat 3 with time 
signature set 4/4, so the note will last until the end of beat 1, bar#2. 
(In the regression test I found the 'Completion_heads_engraver', that's 
how I got the name for it.)

My question:
The notes are notated in the correct way (dotted half on beat3, bar#1, 
correct bar line, next note on beat2, bar#2). But what I observed is 
that there will be no line break at the bar line neither if left to lily 
nor by manually inserting \break in a global section.

Is that correct behaviour of lily? If yes, I would be happy about any 
hints on a workaround.

Kind regards,
Thies Albrecht