Added a test case for "purple include", fixed a bug.

build/test/data/test3.html

+<div class="user">This is a user</div>
+<div class="user">This is a user</div>
+<div class="teacher">This is a teacher</div>

src/ajax/ajax.js

@@ -49,8 +49,10 @@ jQuery.fn.extend({
 			return this.bind("load", url);
 
 		var off = url.indexOf(" ");
-		var selector = url.slice(off, url.length);
-		url = url.slice(0, off);
+		if ( off >= 0 ) {
+			var selector = url.slice(off, url.length);
+			url = url.slice(0, off);
+		}
 
 		callback = callback || function(){};
 

src/ajax/ajaxTest.js

@@ -94,6 +94,15 @@ test("load(String)", function() {
 	$('#first').load("data/name.html", start);
 });
 
+test("load('url selector')", function() {
+	expect(1);
+	stop(true); // check if load can be called with only url
+	$('#first').load("data/test3.html div.user", function(){
+		equals( $(this).children("div").length, 2, "Verify that specific elements were injected" );
+		start();
+	});
+});
+
 test("load(String, Function) - simple: inject text into DOM", function() {
 	expect(2);
 	stop();