diff --git a/test/unit/ready-elements.html b/test/unit/ready-elements.html
index 2fb0b44628..1fdfe384d7 100644
--- a/test/unit/ready-elements.html
+++ b/test/unit/ready-elements.html
@@ -1,4 +1,6 @@
 <script>
+  /* global chai */
+  var assert = chai.assert;
   var configureList = [];
   var readyList = [];