Tie over barline, different stem directions, wrong default tie direction

[Owain Evans]

Hi Bug-Lily List,

I found this very trivial issue with tie default behaviour.
I am changing the tie direction, which is fine, but the default
would be nice to have.

% Ties over barline should have
% automatic behaviour of being up
% (if 1st note stemDown, 2nd note stemUp).
% works as expected in bar but not over barline
\version "2.20.0"

\relative c'' {

 b2 b4 b~ | % undesired behaviour
 b8 g g g g2 |
 b4 b~ b8 g g g % in bar works
 
 % e2 e8 g a b_~ | % this works
 % b b b b b2 |
 
 % g'2 g8 g g, g~ | % undesired behaviour
 % g g g g g2 |
}

Note after first seven bars uncommented, the first undesired behaviour goes 
away!

Kind regards and Many thanks,

Owain Evans