avoid creating a new data cache if we don't need one. Also, short-circuit the case where $.data is used to get the cache id

1 files changed, 14 insertions, 9 deletions

diff --git a/src/data.js b/src/data.js
index 4b557de0c..c18e73cfd 100644
--- a/src/data.js
+++ b/src/data.js
@@ -1,4 +1,5 @@
 var expando = "jQuery" + now(), uuid = 0, windowData = {};

+var emptyObject = {};

 

 jQuery.extend({

 	cache: {},

@@ -10,24 +11,28 @@ jQuery.extend({
 			windowData :

 			elem;

 

-		var id = elem[ expando ], cache = jQuery.cache;

+		var id = elem[ expando ], cache = jQuery.cache, thisCache;

 

 		// Compute a unique ID for the element

 		if(!id) id = elem[ expando ] = ++uuid;

 

-		// Only generate the data cache if we're

-		// trying to access or manipulate it

-		if ( name && !cache[ id ] )

-			cache[ id ] = {};

-

-		var thisCache = cache[ id ];

+		// Handle the case where there's no name immediately

+		if ( !name ) { return id; }

 

+		// Avoid generating a new cache unless none exists and we

+		// want to manipulate it.

+		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 ) thisCache[ name ] = data;

 

 		if(name === true) return thisCache;

-		else if(name) return thisCache[name];

-		else return id;

+		else return thisCache[name];

 	},

 

 	removeData: function( elem, name ) {