diff --git a/parser/tst/equality.sh b/parser/tst/equality.sh
index 6f4ee6082..f0b90379b 100755
--- a/parser/tst/equality.sh
+++ b/parser/tst/equality.sh
@@ -1223,7 +1223,7 @@ done
 
 set -- "${POSITIONAL_ARGS[@]}" # restore positional parameters
 
-if [ $# -eq 0 -o -z $testtype] ; then
+if [ $# -eq 0 -o -z "$testtype" ] ; then
 	run_tests "$@"
 	exit $?
 fi