Re: [PATCH] line-log: protect inner strbuf from free

> > The whole thing feels a bit over-engineered with the callback. The graph
> > code is the only one that needs anything beyond a static string. And the
> > way --line-prefix interacts with it is odd, since some callers override
> > the callback (e.g., "range-diff --line-prefix=foo" is accepted, but
> > doesn't do anything). I don't think there's a bug anybody cares about,
> > but, well...it's not how I would have written it. ;)
> 
> Thanks for exploring this with the diff you sent. It's subtle, but you
> did a good job of recognizing that when the callback is used without
> a 'graph' value, it returns opt->line_prefix.
> 
> > +	if (!graph)
> > +		return opt->line_prefix;
> 
> I was wondering why there was no need to edit graph_setup_line_prefix()
> in your diff, and this explains why. Your change is simple enough to
> handle that change while being robust to a future assignment of the
> callback data.