too much recursion with animate( params, options ) [when options is a var]

[adrien.gibrat]

options.old (set in $.speed for queueing purpose) seems to store too much recursive call and freeze the browser when called more than x times, in firebug error message are:

too much recursion

fn.constructor != Array && /^{[\s[]?function/.test( fn + "" );}

in jquery.js (ligne 619)

too much recursion

if ( jQuery.isFunction( opt.old ) )

in jquery.js (ligne 3158)

To resolve this bug:

speed: function(speed, easing, fn) { var opt = speed && speed.constructor == Object ? speed : {...}; ...

should be:

speed: function(speed, easing, fn) { var opt = speed && speed.constructor == Object ? jQuery.extend({},speed) : {...}; ...

[cdmckay]

I had this problem too.

Basically, if you re-use the "options" parameter object for many animations, you'll get a infinite loop.

Please update the animate() documentation to say that the "options" parameter is modified by animate() and cannot be re-used.

Better yet, why not make animate() make a copy of the "options" parameter object so that this bug will not occur anymore.

[cdmckay]

This bug still occurs as of 1.4.2.

[desandro]

​Stephen Rushing found a good work-around using $.extend inside $.fn.animate.

var animationOptions = {
    duration: 1000,
    easing: 'linear',
    queue: false
}

$(elem).animate(props, $.extend( true, [], animationOptions) )

[dmethvin]

Agreed, we should either document options as mutated or make a copy.

[john]

Fixed ​http://github.com/jquery/jquery/commit/f10057bc481753d92ebfb8dfcef5197af5d76972