Handle unset value attributes consistently depending on property existence. Supplements #9328.

src/attributes.js

@@ -343,8 +343,8 @@ jQuery.extend({
 				return value;
 			}
 
-		} else if ( hooks && "get" in hooks && notxml ) {
-			return hooks.get( elem, name );
+		} else if ( hooks && "get" in hooks && notxml && (ret = hooks.get( elem, name )) !== null ) {
+			return ret;
 
 		} else {
 
@@ -495,12 +495,13 @@ boolHook = {
 // Use the formHook for button elements in IE6/7 (#1954)
 jQuery.attrHooks.value = {
 	get: function( elem, name ) {
+		var ret;
 		if ( formHook && jQuery.nodeName( elem, "button" ) ) {
 			return formHook.get( elem, name );
 		}
 		return name in elem ?
 			elem.value :
-			elem.getAttribute( name );
+			null;
 	},
 	set: function( elem, value, name ) {
 		if ( formHook && jQuery.nodeName( elem, "button" ) ) {

test/unit/attributes.js

@@ -40,7 +40,7 @@ test("jQuery.attrFix/jQuery.propFix integrity test", function() {
 });
 
 test("attr(String)", function() {
-	expect(43);
+	expect(45);
 
 	equals( jQuery("#text1").attr("type"), "text", "Check for type attribute" );
 	equals( jQuery("#radio1").attr("type"), "radio", "Check for type attribute" );
@@ -126,6 +126,8 @@ test("attr(String)", function() {
 	ok( jQuery("<div/>").attr("title") === undefined, "Make sure undefined is returned when no attribute is found." );
 	equal( jQuery("<div/>").attr("title", "something").attr("title"), "something", "Set the title attribute." );
 	ok( jQuery().attr("doesntexist") === undefined, "Make sure undefined is returned when no element is there." );
+	equal( jQuery("<div/>").attr("value"), undefined, "An unset value on a div returns undefined." );
+	equal( jQuery("<input/>").attr("value"), "", "An unset value on an input returns current value." );
 });
 
 if ( !isLocal ) {