Event: Fix chaining .on() with null handlers

Fixes gh-2812
Close gh-2825

2 files changed, 9 insertions, 2 deletions

diff --git a/src/event.js b/src/event.js
index e9d1053dc..6d60b4c11 100644
--- a/src/event.js
+++ b/src/event.js
@@ -71,7 +71,7 @@ function on( elem, types, selector, data, fn, one ) {
 	if ( fn === false ) {
 		fn = returnFalse;
 	} else if ( !fn ) {
-		return this;
+		return elem;
 	}
 
 	if ( one === 1 ) {
diff --git a/test/unit/event.js b/test/unit/event.js
index 6cccb8d1a..04ca615eb 100644
--- a/test/unit/event.js
+++ b/test/unit/event.js
@@ -6,7 +6,7 @@ QUnit.module( "event", {
 } );
 
 QUnit.test( "null or undefined handler", function( assert ) {
-	assert.expect( 2 );
+	assert.expect( 4 );
 
 	// Supports Fixes bug #7229
 	try {
@@ -18,6 +18,13 @@ QUnit.test( "null or undefined handler", function( assert ) {
 		jQuery( "#firstp" ).on( "click", undefined );
 		assert.ok( true, "Passing an undefined handler will not throw an exception" );
 	} catch ( e ) {}
+
+	var expectedElem = jQuery( "#firstp" );
+	var actualElem = expectedElem.on( "click", null );
+	assert.equal(actualElem, expectedElem, "Passing a null handler should return the original element");
+
+	actualElem = expectedElem.on( "click", undefined );
+	assert.equal(actualElem, expectedElem, "Passing a null handler should return the original element");
 } );
 
 QUnit.test( "on() with non-null,defined data", function( assert ) {