Ticket #6808. Changes data() so on plain objects, it uses a function to contain the cache ID to avoid it being JSON serialized.

Author: InfinitiesLoop

src/data.js

@@ -46,13 +46,30 @@ jQuery.extend({
 		// Avoid generating a new cache unless none exists and we
 		// want to manipulate it.
 		if ( typeof name === "object" ) {
-			cache[ id ] = jQuery.extend(true, {}, name);
+			if ( isNode ) {
+				cache[ id ] = jQuery.extend(true, {}, name);
+			} else {
+				cache[ id ] = function() {
+					return jQuery.extend(true, {}, name);
+				}
+			}
 
 		} else if ( !cache[ id ] ) {
-			cache[ id ] = {};
+			if ( isNode ) {
+				cache[ id ] = {};
+			} else {
+				var store = {};
+				cache[ id ] = function() {
+					return store;
+				}
+			}
+			
 		}
 
 		thisCache = cache[ id ];
+		if ( !isNode ) {
+			thisCache = thisCache();
+		}
 
 		// Prevent overriding the named cache with undefined values
 		if ( data !== undefined ) {
@@ -71,8 +88,12 @@ jQuery.extend({
 			windowData :
 			elem;
 
-		var id = elem[ jQuery.expando ], cache = jQuery.cache,
-			isNode = elem.nodeType, thisCache = isNode ? cache[ id ] : id;
+		var isNode = elem.nodeType,
+			id = elem[ jQuery.expando ], cache = jQuery.cache;
+		if ( id && !isNode ) {
+			id = id();
+		}
+		var thisCache = cache[ id ];
 
 		// If we want to remove a specific section of the element's data
 		if ( name ) {

test/unit/data.js

@@ -1,13 +1,14 @@
 module("data");
 
 test("expando", function(){
-	expect(6);
+	expect(7);
 
 	equals("expando" in jQuery, true, "jQuery is exposing the expando");
 
 	var obj = {};
 	jQuery.data(obj);
 	equals( jQuery.expando in obj, true, "jQuery.data adds an expando to the object" );
+	equals( typeof obj[jQuery.expando], "function", "jQuery.data adds an expando to the object as a function" );
 
 	obj = {};	
 	jQuery.data(obj, 'test');
@@ -17,7 +18,7 @@ test("expando", function(){
 	jQuery.data(obj, "foo", "bar");
 	equals( jQuery.expando in obj, true, "jQuery.data added an expando to the object" );
 
-	var id = obj[jQuery.expando];
+	var id = obj[jQuery.expando]();
 	equals( id in jQuery.cache, false, "jQuery.data did not add an entry to jQuery.cache" );
 
 	equals( id.foo, "bar", "jQuery.data worked correctly" );
@@ -54,7 +55,7 @@ test("jQuery.data", function() {
 	jQuery.data( obj, "prop", true );
 
 	ok( obj[ jQuery.expando ], "Data is being stored on the object." );
-	ok( obj[ jQuery.expando ].prop, "Data is being stored on the object." );
+	ok( obj[ jQuery.expando ]().prop, "Data is being stored on the object." );
 
 	equals( jQuery.data( obj, "prop" ), true, "Make sure the right value is retrieved." );
 });