block rest auto width to text?

[David Bobroff]

I'm using the \markup a lot with multimeasure rests.  I find that I have
to set the minimum-length a rearly every time to make sure that the
multimeasureRestText doesn't spill over the barline(s).  Is there a way
to make the multimeasure rests take the width of the text (or the text
width plus a bit extra) as the minimum-length in order to automate this?

-David Bobroff