real_path(): reject the empty string

diff --git a/t/t2017-checkout-orphan.sh b/t/t2017-checkout-orphan.sh
index 0e3b8582f2a3edebb0d9eea7fcebaa88f305fd73..655f278c5f87926311979732eb6c129a14dd87d3 100755 (executable)
--- a/t/t2017-checkout-orphan.sh
+++ b/t/t2017-checkout-orphan.sh
@@ -116,4 +116,10 @@ test_expect_success '--orphan refuses to switch if a merge is needed' '
        git reset --hard
 '
 
+test_expect_success 'cannot --detach on an unborn branch' '
+       git checkout master &&
+       git checkout --orphan new &&
+       test_must_fail git checkout --detach
+'
+
 test_done