[PATCH 2/2 v2] checkout: add a test for creating a new branch with regexp as a starting point

["Dmitry V. Levin" <ldv@altlinux.org>]

Reported-by: Ivan Zakharyaschev <imz@altlinux.org>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
---
 t/t2018-checkout-branch.sh |   25 +++++++++++++++++++++----
 1 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/t/t2018-checkout-branch.sh b/t/t2018-checkout-branch.sh
index 1caffea..6ada870 100755
--- a/t/t2018-checkout-branch.sh
+++ b/t/t2018-checkout-branch.sh
@@ -4,12 +4,13 @@ test_description='checkout '
 
 . ./test-lib.sh
 
-# Arguments: <branch> <sha> [<checkout options>]
+# Arguments: <branch> <start_point> [<checkout options>]
 #
 # Runs "git checkout" to switch to <branch>, testing that
 #
 #   1) we are on the specified branch, <branch>;
-#   2) HEAD is <sha>; if <sha> is not specified, the old HEAD is used.
+#   2) HEAD points to the same commit as <start_point> does;
+#      if <start_point> is not specified, the old HEAD is used.
 #
 # If <checkout options> is not specified, "git checkout" is run with -b.
 do_checkout() {
@@ -17,7 +18,8 @@ do_checkout() {
 	exp_ref="refs/heads/$exp_branch" &&
 
 	# if <sha> is not specified, use HEAD.
-	exp_sha=${2:-$(git rev-parse --verify HEAD)} &&
+	start_point=${2:-HEAD}
+	exp_sha=$(git rev-parse --verify $start_point) &&
 
 	# default options for git checkout: -b
 	if [ -z "$3" ]; then
@@ -26,7 +28,7 @@ do_checkout() {
 		opts="$3"
 	fi
 
-	git checkout $opts $exp_branch $exp_sha &&
+	git checkout $opts $exp_branch $start_point &&
 
 	test $exp_ref = $(git rev-parse --symbolic-full-name HEAD) &&
 	test $exp_sha = $(git rev-parse --verify HEAD)
@@ -118,7 +120,22 @@ test_expect_success 'checkout -b to an existing branch fails' '
 	test_must_fail do_checkout branch2 $HEAD2
 '
 
+test_expect_failure 'checkout -b new_branch :/regexp' '
+	# clean up from previous test
+	git reset --hard &&
+
+	do_checkout old_regexp_branch branch1 &&
+	# The first commit in this test should not be referenced by
+	# other branches or tags.
+	test_commit first a a "" &&
+	test_commit second &&
+
+	do_checkout new_regexp_branch :/first
+'
+
 test_expect_success 'checkout -B to an existing branch resets branch to HEAD' '
+	# clean up from previous test
+	git reset --hard &&
 	git checkout branch1 &&
 
 	do_checkout branch2 "" -B
-- 
1.7.2.1