diff --git a/tests/hash.sh b/tests/hash.sh
index b3f3fa5bf9..5022ea2469 100644
--- a/tests/hash.sh
+++ b/tests/hash.sh
@@ -1,7 +1,7 @@
 source common.sh
 
 try () {
-    echo -n "$2" > $TEST_ROOT/vector
+    printf "%s" "$2" > $TEST_ROOT/vector
     hash=$($nixhash $EXTRA --flat --type "$1" $TEST_ROOT/vector)
     if test "$hash" != "$3"; then
         echo "hash $1, expected $3, got $hash"