jQuery Clone Bug 1.4.2+

[ambar]

code

Array.prototype.xyzz = function (arg) {
	console.log(1,this,arg);
};
Array.prototype.xyzzz = function (arg) {
	console.log(2,this,arg);
};

$(function() {
	$('button').click(function () {
		$('div.demo').clone(true).appendTo( 'body' );
	})
	$('div.demo').click(function () {
		console.log('click..');
	})    
});

click the new div will trigger this bug.

bug src

// event.js, jQuery.event.add:
// before jQuery 1.4.1
handlers = events[ type ] = {};
// jQuery 1.4.2+
handlers = events[ type ] = [];

// manipulation.js, jQuery.clone : , cloneCopyEvent():
for ( var type in events ) {
	for ( var handler in events[ type ] ) {
		jQuery.event.add( this, type, events[ type ][ handler ], events[ type ][ handler ].data );
	}
}

resolve

there is no hasOwnProperty() check in for...in loop, use each() is better.

var self = this;
for ( var type in events ) {
	jQuery.each(events[ type ],function(idx,evt) {
		jQuery.event.add( self, type, evt.handler, evt.data );
	});
}

[ambar]

​http://jsfiddle.net/ambar/qQkYA/

[Section_Ei8ht]

Came here to submit this exact bug. Could be solved using either each() or a for statement rather than a for-in statement as the nested loop.

[Rick Waldron]

If you augment or extend native/host objects, such as Array.prototype, your code will exhibit unexpected behaviour

[Section_Ei8ht]

I apologize if this comment comes across as harsh, but I disagree with the reason for invalidating this ticket. jQuery has a no conflict mode to allow it to be used together with libraries like Prototype, but Prototype modifies the prototypes of several native objects (Array, in this case), which makes this a bug in the compatibility of jQuery with other libraries. You shouldn't say that the fix for this problem is to simply not do it when your documentation says that you can.

It's a one line change, and I respectfully feel that the reason supplied for closing this ticket seems to me to be against the entire mantra of jQuery itself (everything being contained in the jQuery namespace), and a cop-out answer.

I've submitted a pull request to the jQuery github repository that fixes this ticket: ​https://github.com/jquery/jquery/pull/138

[dmethvin]

Duplicate of #6355.