Re: [PATCH 4/8] interpret_branch_name: allow callers to restrict expansions

> Jeff King <peff@peff.net> writes:
> 
> > The original purpose of interpret_branch_name() was to be used by
> > get_sha1() in resolving refs.  As such, some of its expansions may
> > point to refs outside of the local "refs/heads" namespace.
> 
> I am not sure the reference to "get_sha1()" is entirely correct.
> 
> Until it was renamed at 431b1969fc ("Rename interpret/substitute
> nth_last_branch functions", 2009-03-21), the function was called
> interpret_nth_last_branch() which was originally introduced for the
> name, not sha1, at ae5a6c3684 ("checkout: implement "@{-N}" shortcut
> name for N-th last branch", 2009-01-17).  The use of the same syntax
> and function for the object name came a bit later.
> 
> But I think that is an insignificant detail.  Let's read on.

> > @@ -405,7 +405,7 @@ int refname_match(const char *abbrev_name, const char *full_name)
> >  static char *substitute_branch_name(const char **string, int *len)
> >  {
> >  	struct strbuf buf = STRBUF_INIT;
> > -	int ret = interpret_branch_name(*string, *len, &buf);
> > +	int ret = interpret_branch_name(*string, *len, &buf, 0);
> >  
> >  	if (ret == *len) {
> >  		size_t size;
> 
> This is the one used by dwim_ref/log, so we'd need to allow it to
> resolve to anything, e.g. "@" -> "HEAD", and pretend that the user
> typed that expansion.  OK.