Added support for .data(Object), overwriting the existing data object. Fixes #4284.

src/data.js

@@ -37,21 +37,24 @@ jQuery.extend({
 
 		// Avoid generating a new cache unless none exists and we
 		// want to manipulate it.
-		if ( cache[ id ] ) {
+		if ( typeof name === "object" ) {
+			elem[ expando ] = id;
+			thisCache = cache[ id ] = jQuery.extend(true, {}, name);
+		} else if ( cache[ id ] ) {
 			thisCache = cache[ id ];
 		} else if ( typeof data === "undefined" ) {
 			thisCache = emptyObject;
 		} else {
 			thisCache = cache[ id ] = {};
 		}
-		
+
 		// Prevent overriding the named cache with undefined values
 		if ( data !== undefined ) {
 			elem[ expando ] = id;
 			thisCache[ name ] = data;
 		}
-		
-		return name ? thisCache[ name ] : thisCache;
+
+		return typeof name === "string" ? thisCache[ name ] : thisCache;
 	},
 
 	removeData: function( elem, name ) {
@@ -100,6 +103,11 @@ jQuery.fn.extend({
 	data: function( key, value ){
 		if ( typeof key === "undefined" && this.length ) {
 			return jQuery.data( this[0] );
+
+		} else if ( typeof key === "object" ) {
+			return this.each(function() {
+				jQuery.data( this, key );
+			});
 		}
 
 		var parts = key.split(".");

test/unit/data.js

@@ -25,7 +25,7 @@ test("expando", function(){
 });
 
 test("jQuery.data", function() {
-	expect(6);
+	expect(8);
 	var div = jQuery("#foo")[0];
 	equals( jQuery.data(div, "test"), undefined, "Check for no data exists" );
 	
@@ -43,6 +43,10 @@ test("jQuery.data", function() {
 	
 	jQuery.data(div, "test", null);
 	ok( jQuery.data(div, "test") === null, "Check for null data");
+
+	jQuery.data(div, { "test": "in", "test2": "in2" });
+	equals( jQuery.data(div, "test"), "in", "Verify setting an object in data." );
+	equals( jQuery.data(div, "test2"), "in2", "Verify setting an object in data." );
 });
 
 test(".data()", function() {
@@ -114,6 +118,16 @@ test(".data(String) and .data(String, Object)", function() {
 	$elem.removeData();
 });
 
+test(".data(Object)", function() {
+	expect(2);
+
+	var div = jQuery("<div/>");
+
+	div.data({ "test": "in", "test2": "in2" });
+	equals( div.data("test"), "in", "Verify setting an object in data." );
+	equals( div.data("test2"), "in2", "Verify setting an object in data." );
+});
+
 test("jQuery.removeData", function() {
 	expect(1);
 	var div = jQuery("#foo")[0];