DRY the hover pseudo-event, get the type right, allow override.

Now with working unit test for extra correctness! If external code defines a special.hover event, we won't string-hack "hover" into "mouseenter mouseleave".

src/event.js

@@ -26,6 +26,9 @@ var rnamespaces = /\.(.*)$/,
 			(!m[2] || elem.id === m[2]) &&
 			(!m[3] || m[3].test( elem.className ))
 		);
+	},
+	hoverHack = function( events ) {
+		return jQuery.event.special.hover ? events : events.replace( rhoverHack, "mouseenter$1 mouseleave$1" );
 	};
 
 /*
@@ -76,7 +79,7 @@ jQuery.event = {
 
 		// Handle multiple events separated by a space
 		// jQuery(...).bind("mouseover mouseout", fn);
-		types = types.replace( rhoverHack, "mouseover$1 mouseout$1" ).split( " " );
+		types = hoverHack(types).split( " " );
 		for ( t = 0; t < types.length; t++ ) {
 
 			tns = rtypenamespace.exec( types[t] ) || [];
@@ -166,7 +169,7 @@ jQuery.event = {
 		}
 
 		// Once for each type.namespace in types; type may be omitted
-		types = ( types || "" ).replace( rhoverHack, "mouseover$1 mouseout$1" ).split(" ");
+		types = hoverHack( types || "" ).split(" ");
 		for ( t = 0; t < types.length; t++ ) {
 			tns = rtypenamespace.exec( types[t] ) || [];
 			type = tns[1];

test/unit/event.js

@@ -786,7 +786,9 @@ test("unbind(eventObject)", function() {
 	assert( 0 );
 });
 
-test("hover()", function() {
+test("hover() and hover pseudo-event", function() {
+	expect(2);
+
 	var times = 0,
 		handler1 = function( event ) { ++times; },
 		handler2 = function( event ) { ++times; };
@@ -802,6 +804,24 @@ test("hover()", function() {
 		.mouseenter().mouseleave();
 
 	equals( times, 4, "hover handlers fired" );
+
+	var balance = 0;
+	jQuery( "#firstp" )
+		.bind("hover", function( e ) {
+			if ( e.type === "mouseenter" ) {
+				balance++;
+			} else if ( e.type === "mouseleave" ) {
+				balance--;
+			} else {
+				ok( false, "hover pseudo: unknown event type "+e.type );
+			}
+		})
+		.trigger("mouseenter")
+		.trigger("mouseleave")
+		.unbind("hover")
+		.trigger("mouseenter");
+
+	equals( balance, 0, "hover pseudo-event" );
 });
 
 test("mouseover triggers mouseenter", function() {