Re: Truncating HEAD reflog on branch move

> > diff --git a/reflog-walk.c b/reflog-walk.c
> > index ed99437ad..b7e489ad3 100644
> > --- a/reflog-walk.c
> > +++ b/reflog-walk.c
> > @@ -259,6 +259,8 @@ void fake_reflog_parent(struct reflog_walk_info *info, struct commit *commit)
> >  		/* a root commit, but there are still more entries to show */
> >  		reflog = &commit_reflog->reflogs->items[commit_reflog->recno];
> >  		logobj = parse_object(&reflog->noid);
> > +		if (!logobj)
> > +			logobj = parse_object(&reflog->ooid);
> >  	}
> >  
> >  	if (!logobj || logobj->type != OBJ_COMMIT) {
> 
> We already have a loop to find an entry that is a commit that
> discards any non-commit object before the pre-context of this hunk.
> This "oops, old side is NULL so let's cover it up by using the new
> side" kicks in after that.  I wonder if we can roll that cover-up
> logic into the loop, perhaps like

> 	do {
> 		reflog = &commit_reflog->...[recno];
> 		commit_reflog->recno--;
> -		logobj = parse_object(&reflog->ooid);
> +		logobj = parse_object(is_null_oid(&reflog->ooid) 
> +				? &reflog->noid : &reflog->ooid);
> -	} while (commit_reflog->recno && (logobj && logobj->type != OBJ_COMMIT));
> +	} while (commit_reflog->recno && (!logobj || logobj->type != OBJ_COMMIT));
> -
> -	if (!logobj && commit_reflog->recno >= 0 && is_null_oid(&reflog->ooid)) {
> -		/* a root commit ... */
> -		reflog = &commit_reflog->...[recno];
> -		logobj = parse_object(&reflog->noid);
> -	}