From a38e727925bfad369fc98165f6ff161193397f28 Mon Sep 17 00:00:00 2001
From: Junio C Hamano <junkio@cox.net>
Date: Fri, 22 Jul 2005 19:08:47 -0700
Subject: [PATCH] [PATCH] git-branch: avoid getting confused by empty or
 nonexisting branches.

When not specifying the start point explicitly, we ended up
emitting ^0 in addition to the default HEAD.  Be careful to see
if we have "$2" before finding out which commit to base the new
branch on.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
---
 git-branch-script | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/git-branch-script b/git-branch-script
index ade0abf069..041ca515ae 100755
--- a/git-branch-script
+++ b/git-branch-script
@@ -3,7 +3,13 @@
 . git-sh-setup-script || die "Not a git archive"
 
 branchname="$1"
-rev=$(git-rev-parse --verify --default HEAD "$2"^0) || exit
+case "$2" in
+'')
+	head=HEAD ;;
+*)
+	head="$2^0" ;;
+esac
+rev=$(git-rev-parse --revs-only --verify "$head") || exit
 
 [ -z "$branchname" ] && die "git branch: I want a branch name"
 [ -e "$GIT_DIR/refs/heads/$branchname" ] && die "$branchname already exists"