Fastest jQuery.fn.find

jquery.fn.find.js

/**
 * Fastest jQuery.fn.find
 * @jsperf  http://jsperf.com/jquery-find-vs-jquery-fastestfind
 * @author  RubaXa  <ibnRubaXa@gmail.com>
 * @license MIT
 */


/* global document, jQuery */
document.createElement('div').querySelectorAll && (function ($, originalFind){
	var rbuggyQSA = /[>+~*&|:!=?;]|[\w\]]\s+[\[#.\w]|^#\d/;

	/**
	 * Find elements
	 * @param    {String|jQuery|HTMLElement}   selector
	 * @returns  {jQuery}
	 */
	$.fn.find = function (selector){
		if( (typeof selector === 'string') && !rbuggyQSA.test(selector) ){
			var ret = this.pushStack([], 'find', selector), el, length;

			for( var i = 0, l = this.length; i < l; i++ ){
				el = this[i];
				length = ret.length;

				if( el && el.querySelectorAll ){
					var res = el.querySelectorAll(selector);
					if( res.length ){
						for( var j = 0, jn = res.length; j < jn; j++ ){
							ret[length+j] = res[j];
							ret.length++;
						}
					}

					if( i > 0 ){
						// jQuery: Make sure that the results are unique
						for( var n = length; n < ret.length; n++ ){
							for( var r = 0; r < length; r++ ){
								if( ret[r] === ret[n] ){
									ret.splice(n--, 1);
									break;
								}
							}
						}
					}
				}
			}

			return	ret;
		}

		return    originalFind.call(this, selector);
	};
})(jQuery, jQuery.fn.find);