diff --git a/__tests__/string.spec.js b/__tests__/string.spec.js
index e7202bb..81262d6 100644
--- a/__tests__/string.spec.js
+++ b/__tests__/string.spec.js
@@ -112,7 +112,7 @@ describe('string', () => {
     new Schema({
       v: {
         type: 'string',
-        len: 5,
+        len: 6,
         message: 'haha',
       },
     }).validate({