From de486684e3df1988080fd41c97d5f6ab8e6171ed Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Sun, 13 Jan 2013 20:37:14 -0500
Subject: [PATCH] Fix f860e0bd Firefox failures (cherry picked from commit
 0a3a424e65f66414305bf6a34fc6fd93d3b61c62)

---
 test/unit/event.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/test/unit/event.js b/test/unit/event.js
index 182e10b1a..041920a53 100644
--- a/test/unit/event.js
+++ b/test/unit/event.js
@@ -1234,7 +1234,7 @@ test(".trigger() doesn't bubble load event (#10717)", function() {
 test("Delegated events in SVG (#10791; #13180)", function() {
 	expect(2);
 
-	var e,
+	var instanceRoot, e,
 		svg = jQuery(
 			"<svg height='1' version='1.1' width='1' xmlns='http://www.w3.org/2000/svg'>" +
 			"<defs><rect id='ref' x='10' y='20' width='100' height='60' r='10' rx='10' ry='10'></rect></defs>" +
@@ -1258,10 +1258,11 @@ test("Delegated events in SVG (#10791; #13180)", function() {
 
 	// Fire a native click on an SVGElementInstance (the instance tree of an SVG <use>)
 	// to confirm that it doesn't break our event delegation handling (#13180)
-	if ( document.createEvent ) {
+	instanceRoot = svg.find("#use")[0].instanceRoot;
+	if ( instanceRoot && document.createEvent ) {
 		e = document.createEvent("MouseEvents");
 		e.initEvent( "click", true, true );
-		svg.find("#use")[0].instanceRoot.dispatchEvent( e );
+		instanceRoot.dispatchEvent( e );
 	}
 
 	jQuery("#qunit-fixture").off("click");
-- 
2.39.5