[PATCH 5/8] push, send-pack: support pushing HEAD to real ref name

[Steffen Prohaska <prohaska@zib.de>]

This teaches "push <remote> HEAD" to resolve HEAD on the local
side to its real ref name, e.g. refs/heads/master, and then
use the real ref name on the remote side to search a matching
remote ref.

Signed-off-by: Steffen Prohaska <prohaska@zib.de>
---
 remote.c              |   13 ++++++++++---
 t/t5516-fetch-push.sh |   29 +++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/remote.c b/remote.c
index 8908a19..1c96659 100644
--- a/remote.c
+++ b/remote.c
@@ -575,6 +575,8 @@ static struct ref *try_explicit_object_name(const char *name)
 	unsigned char sha1[20];
 	struct ref *ref;
 	int len;
+	char *real_name = 0;
+	const char *best_name;
 
 	if (!*name) {
 		ref = alloc_ref(20);
@@ -582,12 +584,17 @@ static struct ref *try_explicit_object_name(const char *name)
 		hashclr(ref->new_sha1);
 		return ref;
 	}
-	if (get_sha1(name, sha1))
+	if (get_sha1_with_real_ref(name, sha1, &real_name))
 		return NULL;
-	len = strlen(name) + 1;
+	best_name = real_name ? real_name : name;
+	len = strlen(best_name) + 1;
 	ref = alloc_ref(len);
-	memcpy(ref->name, name, len);
+	memcpy(ref->name, best_name, len);
 	hashcpy(ref->new_sha1, sha1);
+
+	if (real_name) {
+		free(real_name);
+	}
 	return ref;
 }
 
diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh
index 42ca0ff..0ff791a 100755
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@@ -282,6 +282,35 @@ test_expect_success 'push with colon-less refspec (4)' '
 
 '
 
+test_expect_success 'push with HEAD' '
+
+	mk_test heads/master &&
+	git push testrepo HEAD &&
+	check_push_result $the_commit heads/master
+
+'
+
+test_expect_success 'push with HEAD (--create)' '
+
+	mk_test &&
+	git push --create testrepo HEAD &&
+	check_push_result $the_commit heads/master
+
+'
+
+test_expect_success 'push with HEAD nonexisting at remote' '
+
+	mk_test heads/master &&
+	git checkout -b local master &&
+	if git push testrepo HEAD
+	then
+		echo "Oops, should have failed"
+		false
+	else
+		check_push_result $the_first_commit heads/master
+	fi
+'
+
 test_expect_success 'push with dry-run' '
 
 	mk_test heads/master &&
-- 
1.5.3.4.1261.g626eb