-find_matching_branch="/^$headrev "'refs\/heads\//{
- s/^.* refs\/heads\///
- p
- q
-}'
-branch=$(git ls-remote "$url" | sed -n -e "$find_matching_branch")
+# $head is the token given from the command line. If a ref with that
+# name exists at the remote and their values match, we should use it.
+# Otherwise find a ref that matches $headrev.
+find_matching_ref='
+ sub abbr {
+ my $ref = shift;
+ if ($ref =~ s|refs/heads/||) {
+ return $ref;
+ } elsif ($ref =~ s|refs/tags/||) {
+ return "tag $ref";
+ } else {
+ return $ref;
+ }
+ }
+
+ my ($exact, $found);
+ while (<STDIN>) {
+ my ($sha1, $ref, $deref) = /^(\S+)\s+(\S+?)(\^\{\})?$/;
+ next unless ($sha1 eq $ARGV[1]);
+ $found = abbr($ref);
+ if ($ref =~ m|/\Q$ARGV[0]\E$|) {
+ $exact = $found;
+ last;
+ }
+ }
+ if ($exact) {
+ print "$exact\n";
+ } elsif ($found) {
+ print "$found\n";
+ }
+'
+
+ref=$(git ls-remote "$url" | perl -e "$find_matching_ref" "$head" "$headrev")
+