merge with /dev/null as base, instead of punting O==empty case

diff --git a/git-parse-remote.sh b/git-parse-remote.sh
index a9db0cd82558af9bebec083450b35348a1d0b29a..aea7b0e5497fb0727533ea750503193fe308374a 100755 (executable)
--- a/git-parse-remote.sh
+++ b/git-parse-remote.sh
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-. git-sh-setup || die "Not a git archive"
+. git-sh-setup
 
 get_data_source () {
        case "$1" in
@@ -65,8 +65,11 @@ get_remote_default_refs_for_push () {
        esac
 }
 
-# Subroutine to canonicalize remote:local notation
+# Subroutine to canonicalize remote:local notation.
 canon_refs_list_for_fetch () {
+       # Leave only the first one alone; add prefix . to the rest
+       # to prevent the secondary branches to be merged by default.
+       dot_prefix=
        for ref
        do
                force=
@@ -91,7 +94,14 @@ canon_refs_list_for_fetch () {
                heads/* | tags/* ) local="refs/$local" ;;
                *) local="refs/heads/$local" ;;
                esac
-               echo "${force}${remote}:${local}"
+
+               if local_ref_name=$(expr "$local" : 'refs/\(.*\)')
+               then
+                  git-check-ref-format "$local_ref_name" ||
+                  die "* refusing to create funny ref '$local_ref_name' locally"
+               fi
+               echo "${dot_prefix}${force}${remote}:${local}"
+               dot_prefix=.
        done
 }
 
@@ -107,6 +117,9 @@ get_remote_default_refs_for_fetch () {
                echo "refs/heads/${remote_branch}:refs/heads/$1"
                ;;
        remotes)
+               # This prefixes the second and later default refspecs
+               # with a '.', to signal git-fetch to mark them
+               # not-for-merge.
                canon_refs_list_for_fetch $(sed -ne '/^Pull: */{
                                                s///p
                                        }' "$GIT_DIR/remotes/$1")