public function testIndexActionReturnsTrueOnSuccess()
 {
     $postData = ['email' => '*****@*****.**'];
     $messageServiceMock = $this->getMock(Subscriber::class);
     $messageServiceMock->method('getForm')->willReturn(new PreferencesForm());
     $messageServiceMock->method('removeSubscriberFromList')->willReturn(1);
     $serviceManager = $this->getApplicationServiceLocator();
     $serviceManager->setAllowOverride(true);
     $serviceManager->get('UthandoServiceManager')->setService('UthandoNewsletterSubscriber', $messageServiceMock);
     $oPrg = $this->getMock(PostRedirectGet::class);
     $oPrg->expects($this->any())->method('__invoke')->willReturn($postData);
     $pluginManager = $serviceManager->get('ControllerPluginManager');
     $pluginManager->setService('prg', $oPrg);
     $controller = new Preferences();
     $controller->setServiceLocator($serviceManager);
     $controller->setPluginManager($pluginManager);
     $result = $controller->indexAction();
     $this->assertEquals(1, $result['result']);
 }