diff --git a/bin/runner b/bin/runner
index 4c0496a..837710b 100755
--- a/bin/runner
+++ b/bin/runner
@@ -29,7 +29,7 @@ shift $((OPTIND-1))
 
 command=$1
 
-if [ "$1" == "" ]; then
+if [ -z "$1" ]; then
   usage
 fi