strbuf_check_branch_ref(): a helper to check a refname for a branch

This allows a common calling sequence

	strbuf_branchname(&ref, name);
	strbuf_splice(&ref, 0, 0, "refs/heads/", 11);
	if (check_ref_format(ref.buf))
		die(...);

to be refactored into

	if (strbuf_check_branch_ref(&ref, name))
		die(...);

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 4 deletions

diff --git a/branch.c b/branch.c
index 558f092701..62030af4b5 100644
--- a/branch.c
+++ b/branch.c
@@ -135,10 +135,7 @@ void create_branch(const char *head,
 	struct strbuf ref = STRBUF_INIT;
 	int forcing = 0;
 
-	strbuf_branchname(&ref, name);
-	strbuf_splice(&ref, 0, 0, "refs/heads/", 11);
-
-	if (check_ref_format(ref.buf))
+	if (strbuf_check_branch_ref(&ref, name))
 		die("'%s' is not a valid branch name.", name);
 
 	if (resolve_ref(ref.buf, sha1, 1, NULL)) {