Fix #5571. Setters should treat `undefined` as a no-op and be chainable.

src/attributes.js

@@ -12,7 +12,7 @@ var rclass = /[\n\t\r]/g,
 
 jQuery.fn.extend({
 	attr: function( name, value ) {
-		return jQuery.access( this, name, value, true, jQuery.attr );
+		return jQuery.access( this, jQuery.attr, name, value, arguments.length > 1 );
 	},
 
 	removeAttr: function( name ) {
@@ -22,7 +22,7 @@ jQuery.fn.extend({
 	},
 
 	prop: function( name, value ) {
-		return jQuery.access( this, name, value, true, jQuery.prop );
+		return jQuery.access( this, jQuery.prop, name, value, arguments.length > 1 );
 	},
 
 	removeProp: function( name ) {

src/core.js

@@ -801,31 +801,55 @@ jQuery.extend({
 
 	// Mutifunctional method to get and set values to a collection
 	// The value/s can optionally be executed if it's a function
-	access: function( elems, key, value, exec, fn, pass ) {
-		var length = elems.length;
+	access: function( elems, fn, key, value, chainable, emptyGet, pass ) {
+		var exec,
+			bulk = key == null,
+			i = 0,
+			length = elems.length;
 
-		// Setting many attributes
-		if ( typeof key === "object" ) {
-			for ( var k in key ) {
-				jQuery.access( elems, k, key[k], exec, fn, value );
+		// Sets many values
+		if ( key && typeof key === "object" ) {
+			for ( i in key ) {
+				jQuery.access( elems, fn, i, key[i], 1, emptyGet, value );
 			}
-			return elems;
-		}
+			chainable = 1;
 
-		// Setting one attribute
-		if ( value !== undefined ) {
+		// Sets one value
+		} else if ( value !== undefined ) {
 			// Optionally, function values get executed if exec is true
-			exec = !pass && exec && jQuery.isFunction(value);
+			exec = pass === undefined && jQuery.isFunction( value );
+
+			if ( bulk ) {
+				// Bulk operations only iterate when executing function values
+				if ( exec ) {
+					exec = fn;
+					fn = function( elem, key, value ) {
+						return exec.call( jQuery( elem ), value );
+					};
 
-			for ( var i = 0; i < length; i++ ) {
-				fn( elems[i], key, exec ? value.call( elems[i], i, fn( elems[i], key ) ) : value, pass );
+				// Otherwise they run against the entire set
+				} else {
+					fn.call( elems, value );
+					fn = null;
+				}
 			}
 
-			return elems;
+			if ( fn ) {
+				for (; i < length; i++ ) {
+					fn( elems[i], key, exec ? value.call( elems[i], i, fn( elems[i], key ) ) : value, pass );
+				}
+			}
+
+			chainable = 1;
 		}
 
-		// Getting an attribute
-		return length ? fn( elems[0], key ) : undefined;
+		return chainable ?
+			elems :
+
+			// Gets
+			bulk ?
+				fn.call( elems ) :
+				length ? fn( elems[0], key ) : emptyGet;
 	},
 
 	now: function() {

src/css.js

@@ -17,16 +17,11 @@ var ralpha = /alpha\([^)]*\)/i,
 	currentStyle;
 
 jQuery.fn.css = function( name, value ) {
-	// Setting 'undefined' is a no-op
-	if ( arguments.length === 2 && value === undefined ) {
-		return this;
-	}
-
-	return jQuery.access( this, name, value, true, function( elem, name, value ) {
+	return jQuery.access( this, function( elem, name, value ) {
 		return value !== undefined ?
 			jQuery.style( elem, name, value ) :
 			jQuery.css( elem, name );
-	});
+	}, name, value, arguments.length > 1 );
 };
 
 jQuery.extend({

src/data.js

@@ -246,62 +246,69 @@ jQuery.extend({
 
 jQuery.fn.extend({
 	data: function( key, value ) {
-		var parts, attr, name,
+		var parts, part, attr, name, l,
+			elem = this[0],
+			i = 0,
 			data = null;
 
-		if ( typeof key === "undefined" ) {
+		// Gets all values
+		if ( key === undefined ) {
 			if ( this.length ) {
-				data = jQuery.data( this[0] );
+				data = jQuery.data( elem );
 
-				if ( this[0].nodeType === 1 && !jQuery._data( this[0], "parsedAttrs" ) ) {
-					attr = this[0].attributes;
-					for ( var i = 0, l = attr.length; i < l; i++ ) {
+				if ( elem.nodeType === 1 && !jQuery._data( elem, "parsedAttrs" ) ) {
+					attr = elem.attributes;
+					for ( l = attr.length; i < l; i++ ) {
 						name = attr[i].name;
 
 						if ( name.indexOf( "data-" ) === 0 ) {
 							name = jQuery.camelCase( name.substring(5) );
 
-							dataAttr( this[0], name, data[ name ] );
+							dataAttr( elem, name, data[ name ] );
 						}
 					}
-					jQuery._data( this[0], "parsedAttrs", true );
+					jQuery._data( elem, "parsedAttrs", true );
 				}
 			}
 
 			return data;
+		}
 
-		} else if ( typeof key === "object" ) {
+		// Sets multiple values
+		if ( typeof key === "object" ) {
 			return this.each(function() {
 				jQuery.data( this, key );
 			});
 		}
 
-		parts = key.split(".");
-		parts[1] = parts[1] ? "." + parts[1] : "";
+		return jQuery.access( this, function( value ) {
+			parts = key.split( ".", 2 ),
+			parts[1] = parts[1] ? "." + parts[1] : "";
+			part = parts[1] + "!";
 
-		if ( value === undefined ) {
-			data = this.triggerHandler("getData" + parts[1] + "!", [parts[0]]);
+			if ( value === undefined ) {
+				data = this.triggerHandler( "getData" + part, [ parts[0] ] );
 
-			// Try to fetch any internally stored data first
-			if ( data === undefined && this.length ) {
-				data = jQuery.data( this[0], key );
-				data = dataAttr( this[0], key, data );
-			}
+				// Try to fetch any internally stored data first
+				if ( data === undefined && elem ) {
+					data = jQuery.data( elem, key );
+					data = dataAttr( elem, key, data );
+				}
 
-			return data === undefined && parts[1] ?
-				this.data( parts[0] ) :
-				data;
+				return data === undefined && parts[1] ?
+					this.data( parts[0] ) :
+					data;
+			}
 
-		} else {
-			return this.each(function() {
-				var self = jQuery( this ),
-					args = [ parts[0], value ];
+			parts[1] = value;
+			this.each(function() {
+				var self = jQuery( this );
 
-				self.triggerHandler( "setData" + parts[1] + "!", args );
+				self.triggerHandler( "setData" + part, parts );
 				jQuery.data( this, key, value );
-				self.triggerHandler( "changeData" + parts[1] + "!", args );
+				self.triggerHandler( "changeData" + part, parts );
 			});
-		}
+		}, null, value, arguments.length > 1, null, false );
 	},
 
 	removeData: function( key ) {

src/dimensions.js

@@ -1,9 +1,10 @@
 (function( jQuery ) {
 
 // Create width, height, innerHeight, innerWidth, outerHeight and outerWidth methods
-jQuery.each([ "Height", "Width" ], function( i, name ) {
-
-	var type = name.toLowerCase();
+jQuery.each( { Height: "height", Width: "width" }, function( name, type ) {
+	var clientProp = "client" + name,
+		scrollProp = "scroll" + name,
+		offsetProp = "offset" + name;
 
 	// innerHeight and innerWidth
 	jQuery.fn[ "inner" + name ] = function() {
@@ -25,50 +26,40 @@ jQuery.each([ "Height", "Width" ], function( i, name ) {
 			null;
 	};
 
-	jQuery.fn[ type ] = function( size ) {
-		// Get window width or height
-		var elem = this[0];
-		if ( !elem ) {
-			return size == null ? null : this;
-		}
-
-		if ( jQuery.isFunction( size ) ) {
-			return this.each(function( i ) {
-				var self = jQuery( this );
-				self[ type ]( size.call( this, i, self[ type ]() ) );
-			});
-		}
+	jQuery.fn[ type ] = function( value ) {
+		return jQuery.access( this, function( elem, type, value ) {
+			var doc, docElemProp, orig, ret;
 
-		if ( jQuery.isWindow( elem ) ) {
-			// Everyone else use document.documentElement or document.body depending on Quirks vs Standards mode
-			// 3rd condition allows Nokia support, as it supports the docElem prop but not CSS1Compat
-			var docElemProp = elem.document.documentElement[ "client" + name ],
-				body = elem.document.body;
-			return elem.document.compatMode === "CSS1Compat" && docElemProp ||
-				body && body[ "client" + name ] || docElemProp;
+			if ( jQuery.isWindow( elem ) ) {
+				// 3rd condition allows Nokia support, as it supports the docElem prop but not CSS1Compat
+				doc = elem.document;
+				docElemProp = doc.documentElement[ clientProp ];
+				return doc.compatMode === "CSS1Compat" && docElemProp ||
+					doc.body && doc.body[ clientProp ] || docElemProp;
+			}
 
-		// Get document width or height
-		} else if ( elem.nodeType === 9 ) {
-			// Either scroll[Width/Height] or offset[Width/Height], whichever is greater
-			return Math.max(
-				elem.documentElement["client" + name],
-				elem.body["scroll" + name], elem.documentElement["scroll" + name],
-				elem.body["offset" + name], elem.documentElement["offset" + name]
-			);
+			// Get document width or height
+			if ( elem.nodeType === 9 ) {
+				// Either scroll[Width/Height] or offset[Width/Height], whichever is greater
+				doc = elem.documentElement;
+				return Math.max(
+					doc[ clientProp ],
+					elem.body[ scrollProp ], doc[ scrollProp ],
+					elem.body[ offsetProp ], doc[ offsetProp ]
+				);
+			}
 
-		// Get or set width or height on the element
-		} else if ( size === undefined ) {
-			var orig = jQuery.css( elem, type ),
+			// Get width or height on the element
+			if ( value === undefined ) {
+				orig = jQuery.css( elem, type );
 				ret = parseFloat( orig );
+				return jQuery.isNumeric( ret ) ? ret : orig;
+			}
 
-			return jQuery.isNumeric( ret ) ? ret : orig;
-
-		// Set the width or height on the element (default to pixels if value is unitless)
-		} else {
-			return this.css( type, typeof size === "string" ? size : size + "px" );
-		}
+			// Set the width or height on the element
+			jQuery( elem ).css( type, value );
+		}, type, value, arguments.length, null );
 	};
-
 });
 
 })( jQuery );