Re: [PATCH 2/3] cvsimport: use show-ref to support packed refs

[Junio C Hamano <gitster@pobox.com>]

Jeff King <peff@peff.net> writes:

> Since get_headref is useful in contexts where "$remote" is not always
> prepended (see patch 3/3), I think the best solution is:

...

> +	if ($branch eq $opt_o && !$index{branch} &&
> +		!get_headref("$remote/$branch")) {
> +	my $parent = get_headref("$remote/$last_branch");
> +		if (my $sha1 = get_headref("$remote/$mparent")) {

So the definition of get_headref() is to always take everything under
but not including "refs/"?  IOW, the tip of the master branch is asked
with get_headref("heads/master")?

I think show-ref can easily be confused by its tail matching behaviour,
and is a bad command to use in a context like this.  To be safe, I think
get_headref() should be:

	sub get_headref {
        	my ($it) = (@_);
                my $r = `git-rev-parse --verify "refs/$it"`;
		return undef unless $? == 0;
		chomp $r;
		return $r;
	}