Issue 2256 in lilypond: empty strings: tabStaff insists on stringnumbers and looses notes

[lilypond]

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

New issue 2256 by address@hidden: empty strings: tabStaff insists on  
stringnumbers and looses notes
http://code.google.com/p/lilypond/issues/detail?id=2256

S. Runkel writes :

\version 2.14.2
\makeStringTuning #'custom-tuning <c g d' a'>
\score {
 \new TabStaff {
   \set TabStaff.stringTunings = #custom-tuning
   <c g'> 1 <c\4 g'> 1
 }
}

%{
results in:
----------
---5--5---
----------
------0---

But should read:
----------
---5--5---
----------
---0--0---

%}