X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=git-checkout-script;h=b31ded716d470a4975512ebc4cb912b3adb5fb7f;hb=b893f09104ee5f1d8710dfe17cdf1cbac995f17a;hp=4b3ae4adc262a7255882d4faff09c0e3a5f5afad;hpb=9661c256400d1a17a27e014592f887359f74707e;p=git.git

diff --git a/git-checkout-script b/git-checkout-script
index 4b3ae4ad..b31ded71 100755
--- a/git-checkout-script
+++ b/git-checkout-script
@@ -1,18 +1,28 @@
 #!/bin/sh
-: ${GIT_DIR=.git}
+. git-sh-setup-script || die "Not a git archive"
+
 old=$(git-rev-parse HEAD)
 new=
 force=
 branch=
+newbranch=
 while [ "$#" != "0" ]; do
     arg="$1"
     shift
     case "$arg" in
+	"-b")
+		newbranch="$1"
+		shift
+		[ -z "$newbranch" ] &&
+			die "git checkout: -b needs a branch name"
+		[ -e "$GIT_DIR/refs/heads/$newbranch" ] &&
+			die "git checkout: branch $newbranch already exists"
+		;;
 	"-f")
 		force=1
 		;;
 	*)
-		rev=$(git-rev-parse "$arg")
+		rev=$(git-rev-parse --verify "$arg^0") || exit
 		if [ -z "$rev" ]; then
 			echo "unknown flag $arg"
 			exit 1
@@ -27,10 +37,19 @@ while [ "$#" != "0" ]; do
 		fi
 		;;
     esac
-    i=$(($i+1))
 done
 [ -z "$new" ] && new=$old
 
+#
+# If we don't have an old branch that we're switching to,
+# and we don't have a new branch name for the target we
+# are switching to, then we'd better just be checking out
+# what we already had
+#
+[ -z "$branch$newbranch" ] &&
+	[ "$new" != "$old" ] &&
+	die "git checkout: you need to specify a new branch name"
+
 if [ "$force" ]
 then
     git-read-tree --reset $new &&
@@ -46,6 +65,12 @@ fi
 # be based on them, since we re-set the index)
 #
 if [ "$?" -eq 0 ]; then
+	if [ "$newbranch" ]; then
+		echo $new > "$GIT_DIR/refs/heads/$newbranch"
+		branch="$newbranch"
+	fi
 	[ "$branch" ] && ln -sf "refs/heads/$branch" "$GIT_DIR/HEAD"
 	rm -f "$GIT_DIR/MERGE_HEAD"
+else
+	exit 1
 fi