diff --git a/lib/ace/test/mockrenderer.js b/lib/ace/test/mockrenderer.js
index 589beabe..5efac2a9 100644
--- a/lib/ace/test/mockrenderer.js
+++ b/lib/ace/test/mockrenderer.js
@@ -101,6 +101,9 @@ MockRenderer.prototype.on = function() {
 MockRenderer.prototype.updateCursor = function() {
 };
 
+MockRenderer.prototype.scrollToX = function(scrollTop) {};
+MockRenderer.prototype.scrollToY = function(scrollLeft) {};
+    
 MockRenderer.prototype.scrollToLine = function(line, center) {
     var lineHeight = { lineHeight: 16 };
     var row = 0;