diff --git a/test/spec/lib/manipulators.js b/test/spec/lib/manipulators.js
index c886d62..df860f2 100644
--- a/test/spec/lib/manipulators.js
+++ b/test/spec/lib/manipulators.js
@@ -9,7 +9,7 @@ describe('manipulators', function() {
   /**
    * @param {string} itemType
    * @param {*} value
-   * @param {*} expected
+   * @param {*} [expected]
    * @return {void}
    */
   function testSetGet(itemType, value, expected) {