protected function setUp() {
        global $PAGE, $SITE;
        parent::setUp();

        $this->resetAfterTest(true);

        $PAGE->set_url('/');
        $PAGE->set_course($SITE);

        $tempnode = new exposed_global_navigation();
        // Create an initial tree structure to work with
        $cat1 = $tempnode->add('category 1', null, navigation_node::TYPE_CATEGORY, null, 'cat1');
        $cat2 = $tempnode->add('category 2', null, navigation_node::TYPE_CATEGORY, null, 'cat2');
        $cat3 = $tempnode->add('category 3', null, navigation_node::TYPE_CATEGORY, null, 'cat3');
        $sub1 = $cat2->add('sub category 1', null, navigation_node::TYPE_CATEGORY, null, 'sub1');
        $sub2 = $cat2->add('sub category 2', null, navigation_node::TYPE_CATEGORY, null, 'sub2');
        $sub3 = $cat2->add('sub category 3', null, navigation_node::TYPE_CATEGORY, null, 'sub3');
        $course1 = $sub2->add('course 1', null, navigation_node::TYPE_COURSE, null, 'course1');
        $course2 = $sub2->add('course 2', null, navigation_node::TYPE_COURSE, null, 'course2');
        $course3 = $sub2->add('course 3', null, navigation_node::TYPE_COURSE, null, 'course3');
        $section1 = $course2->add('section 1', null, navigation_node::TYPE_SECTION, null, 'sec1');
        $section2 = $course2->add('section 2', null, navigation_node::TYPE_SECTION, null, 'sec2');
        $section3 = $course2->add('section 3', null, navigation_node::TYPE_SECTION, null, 'sec3');
        $act1 = $section2->add('activity 1', null, navigation_node::TYPE_ACTIVITY, null, 'act1');
        $act2 = $section2->add('activity 2', null, navigation_node::TYPE_ACTIVITY, null, 'act2');
        $act3 = $section2->add('activity 3', null, navigation_node::TYPE_ACTIVITY, null, 'act3');
        $res1 = $section2->add('resource 1', null, navigation_node::TYPE_RESOURCE, null, 'res1');
        $res2 = $section2->add('resource 2', null, navigation_node::TYPE_RESOURCE, null, 'res2');
        $res3 = $section2->add('resource 3', null, navigation_node::TYPE_RESOURCE, null, 'res3');
        $tempnode->find('course2', navigation_node::TYPE_COURSE)->make_active();

        $page = new navigation_exposed_moodle_page();
        $page->set_url($PAGE->url);
        $page->set_context($PAGE->context);

        $navigation = new exposed_global_navigation($page);
        $navigation->children = $tempnode->children;
        $navigation->set_initialised();
        $page->set_navigation($navigation);

        $this->cache = new navigation_cache('simpletest_nav');
        $this->node = new exposed_navbar($page);
    }