Slightly better error reporting.

scripts/runtest.sh

diff --git a/scripts/runtest.sh b/scripts/runtest.sh
index b1e7076..9ee6cd8 100644
--- a/scripts/runtest.sh
+++ b/scripts/runtest.sh
@@ -147,7 +147,7 @@
   if ! verbose_has quiet && { [ -n "$DIFF" ] || verbose_has spam; }
   then
     [ ! -z "$4" ] && printf "%s\n" "echo -ne \"$4\" > input"
-    printf "%s\n" "echo -ne '$5' |$EVAL $2"
+    printf "%s\n" "echo -ne '$5' |$EVAL ${2@Q}"
     [ -n "$DIFF" ] && printf "%s\n" "$DIFF"
   fi