diff --git a/test/unit/dom-repeat.html b/test/unit/dom-repeat.html
index 7ab64294b9..00f1bedfad 100644
--- a/test/unit/dom-repeat.html
+++ b/test/unit/dom-repeat.html
@@ -127,6 +127,7 @@ <h4>x-repeat-chunked</h4>
 
   <script>
   (function() {
+    'use strict';
   /* global limited inDocumentRepeater inDocumentContainer inDocumentContainerOrig stamped:true chunked nonUpgrade*/
 
     /*
@@ -3607,7 +3608,7 @@ <h4>x-repeat-chunked</h4>
       test('increase limit above items.length', function() {
         limited.$.repeater.__limit = 30;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 20);
         checkItemOrder(stamped);
       });
@@ -3629,7 +3630,7 @@ <h4>x-repeat-chunked</h4>
       test('negative limit', function() {
         limited.$.repeater.__limit = -10;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 0);
       });
 
@@ -3675,7 +3676,7 @@ <h4>x-repeat-chunked</h4>
       test('increase limit above items.length', function() {
         limited.$.repeater.__limit = 30;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 20);
         checkItemOrder(stamped);
       });
@@ -3697,7 +3698,7 @@ <h4>x-repeat-chunked</h4>
       test('negative limit', function() {
         limited.$.repeater.__limit = -10;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 0);
       });
 
@@ -3745,7 +3746,7 @@ <h4>x-repeat-chunked</h4>
       test('increase limit above items.length', function() {
         limited.$.repeater.__limit = 30;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 10);
           checkItemOrder(stamped);
       });
@@ -3767,7 +3768,7 @@ <h4>x-repeat-chunked</h4>
       test('negative limit', function() {
         limited.$.repeater.__limit = -10;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 0);
       });
 
@@ -3817,7 +3818,7 @@ <h4>x-repeat-chunked</h4>
       test('increase limit above items.length', function() {
         limited.$.repeater.__limit = 30;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 10);
         checkItemOrder(stamped);
       });
@@ -3839,7 +3840,7 @@ <h4>x-repeat-chunked</h4>
       test('negative limit', function() {
         limited.$.repeater.__limit = -10;
         limited.$.repeater.render();
-        stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
+        var stamped = limited.root.querySelectorAll('*:not(template):not(dom-repeat)');
         assert.equal(stamped.length, 0);
       });