From d483ce0a9c8b19dafa70be93ca071673b86a65e2 Mon Sep 17 00:00:00 2001
From: Jared Grippe <jared@deadlyicon.com>
Date: Sat, 9 Oct 2010 17:32:54 -0700
Subject: [PATCH] added jQuery.subclass

---
 src/core.js       | 31 ++++++++++++++++----
 test/unit/core.js | 72 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+), 5 deletions(-)

diff --git a/src/core.js b/src/core.js
index 4361577e..0bf0cb4b 100644
--- a/src/core.js
+++ b/src/core.js
@@ -3,7 +3,7 @@ var jQuery = (function() {
 // Define a local copy of jQuery
 var jQuery = function( selector, context ) {
 		// The jQuery object is actually just the init constructor 'enhanced'
-		return new jQuery.fn.init( selector, context );
+		return new jQuery.fn.init( selector, context, rootjQuery );
 	},
 
 	// Map over jQuery in case of overwrite
@@ -78,7 +78,8 @@ var jQuery = function( selector, context ) {
 	class2type = {};
 
 jQuery.fn = jQuery.prototype = {
-	init: function( selector, context ) {
+	constructor: jQuery,
+	init: function( selector, context, rootjQuery ) {
 		var match, elem, ret, doc;
 
 		// Handle $(""), $(null), or $(undefined)
@@ -112,6 +113,7 @@ jQuery.fn = jQuery.prototype = {
 
 				// HANDLE: $(html) -> $(array)
 				if ( match[1] ) {
+					context = context instanceof jQuery ? context[0] : context;
 					doc = (context ? context.ownerDocument || context : document);
 
 					// If a single string is passed in and it's a single tag
@@ -171,7 +173,7 @@ jQuery.fn = jQuery.prototype = {
 			// HANDLE: $(expr, context)
 			// (which is just equivalent to: $(context).find(expr)
 			} else {
-				return jQuery( context ).find( selector );
+				return this.constructor( context ).find( selector );
 			}
 
 		// HANDLE: $(function)
@@ -222,7 +224,7 @@ jQuery.fn = jQuery.prototype = {
 	// (returning the new matched element set)
 	pushStack: function( elems, name, selector ) {
 		// Build a new jQuery matched element set
-		var ret = jQuery();
+		var ret = this.constructor();
 
 		if ( jQuery.isArray( elems ) ) {
 			push.apply( ret, elems );
@@ -287,7 +289,7 @@ jQuery.fn = jQuery.prototype = {
 	},
 
 	end: function() {
-		return this.prevObject || jQuery(null);
+		return this.prevObject || this.constructor(null);
 	},
 
 	// For internal use only.
@@ -960,6 +962,25 @@ jQuery.extend({
 		return { browser: match[1] || "", version: match[2] || "0" };
 	},
 
+	subclass: function(){
+		function jQuerySubclass( selector, context ) {
+			return new jQuerySubclass.fn.init( selector, context );
+		}
+		jQuerySubclass.superclass = this;
+		jQuerySubclass.fn = jQuerySubclass.prototype = this();
+		jQuerySubclass.fn.constructor = jQuerySubclass;
+		jQuerySubclass.subclass = this.subclass;
+		jQuerySubclass.fn.init = function init( selector, context ) {
+			if (context && context instanceof jQuery && !(context instanceof jQuerySubclass)){
+				context = jQuerySubclass(context);
+			}
+			return jQuery.fn.init.call( this, selector, context, rootjQuerySubclass );
+		};
+		jQuerySubclass.fn.init.prototype = jQuerySubclass.fn;
+		var rootjQuerySubclass = jQuerySubclass(document);
+		return jQuerySubclass;
+	},
+
 	browser: {}
 });
 
diff --git a/test/unit/core.js b/test/unit/core.js
index bfb2f1cf..d26e7c56 100644
--- a/test/unit/core.js
+++ b/test/unit/core.js
@@ -1063,3 +1063,75 @@ test("jQuery.when()", function() {
 		});
 	}
 });
+
+test("jQuery.subclass", function(){
+	expect(378);
+
+	var Subclass = jQuery.subclass(),
+			SubclassSubclass = Subclass.subclass(),
+			jQueryDocument = jQuery(document),
+			selectors, contexts, methods, method, arg, description;
+
+	jQueryDocument.toString = function(){ return 'jQueryDocument'; };
+
+	Subclass.fn.subclassMethod = function(){};
+	SubclassSubclass.fn.subclassSubclassMethod = function(){};
+
+	selectors = [
+		'body',
+		'html, body',
+		'<div></div>'
+	]
+
+	methods = [ // all methods that return a new jQuery instance
+		['eq', 1],
+		['add', document],
+		['end'],
+		['has'],
+		['closest', 'div'],
+		['filter', document],
+		['find']
+	]
+
+	contexts = [undefined, document, jQueryDocument];
+
+	jQuery.each(selectors, function(i, selector){
+
+		jQuery.each(methods, function(){
+			method = this[0]
+			arg = this[1]
+
+			jQuery.each(contexts, function(i, context){
+
+				description = '("'+selector+'", '+context+').'+method+'('+(arg||'')+')';
+
+				same(
+					jQuery(selector, context)[method](arg).subclassMethod, undefined,
+					'jQuery'+description+' doesnt have Subclass methods'
+				);
+				same(
+					jQuery(selector, context)[method](arg).subclassSubclassMethod, undefined,
+					'jQuery'+description+' doesnt have SubclassSubclass methods'
+				);
+				same(
+					Subclass(selector, context)[method](arg).subclassMethod, Subclass.fn.subclassMethod,
+					'Subclass'+description+' has Subclass methods'
+				);
+				same(
+					Subclass(selector, context)[method](arg).subclassSubclassMethod, undefined,
+					'Subclass'+description+' doesnt have SubclassSubclass methods'
+				);
+				same(
+					SubclassSubclass(selector, context)[method](arg).subclassMethod, Subclass.fn.subclassMethod,
+					'SubclassSubclass'+description+' has Subclass methods'
+				);
+				same(
+					SubclassSubclass(selector, context)[method](arg).subclassSubclassMethod, SubclassSubclass.fn.subclassSubclassMethod,
+					'SubclassSubclass'+description+' has SubclassSubclass methods'
+				);
+
+			});
+		});
+	});
+
+});