Testing using phpunit

I want the coding for testing the admin_add using php unit in cake php
my code

public function testAdminAdd() {
#define sample passing data
$sampleDataPass=array(
‘AdminUser’=>array(
‘first_name’=>‘chitra’,
‘email’=>‘chitra@2basetechnologies.com’,
‘password’=>‘chitra’,
‘super_admin’=>‘1’,
‘active’=>‘1’,
‘deleted’=>‘0’
));

	#test action
	$this->AdminUsers->request->data=$sampleDataPass;
	$result=$this->testAction('admin/AdminUsers/add',array('data'=>$sampleDataPass));
            $this->assertEmpty($this->AdminUsers->AdminUser->ValidationErrors);
	}

While i use this code my test result is display a blank page