[TASK] Adding return value to send mail method, to determine if it was successfull

Classes/Controller/MailController.php

@@ -274,10 +274,14 @@ class MailController extends ActionController {
 		$mailTemplateService->setSubject($this->settings['mail']['test']['subject']);
 		$mailTemplateService->setTemplateName($selectedTemplateKey);
 		$mailTemplateService->setExtensionKey($selectedExtensionKey);
-		$mailTemplateService->sendEmail();
 
-		$message = LocalizationUtility::translate('backend.success_mail', 'sg_mail');
-		$this->addFlashMessage($message, '', FlashMessage::OK);
+		if ($mailTemplateService->sendEmail()) {
+			$message = LocalizationUtility::translate('backend.success_mail', 'sg_mail');
+			$this->addFlashMessage($message, '', FlashMessage::OK);
+		} else {
+			$message = LocalizationUtility::translate('backend.failure_mail', 'sg_mail');
+			$this->addFlashMessage($message, '', FlashMessage::ERROR);
+		}
 
 		$arguments = $this->request->getArguments();
 		$this->redirect('index', NULL, NULL, $arguments);

Classes/Service/MailTemplateService.php

@@ -188,6 +188,8 @@ class MailTemplateService {
 
 	/**
 	 * Send the Email
+	 *
+	 * @return boolean email was sent or added to mail queue successfully?
 	 */
 	public function sendEmail() {
 
@@ -199,6 +201,11 @@ class MailTemplateService {
 		$template = $this->templateRepository->findTemplate(
 			$this->extensionKey, $this->templateName, $this->language
 		)->getFirst();
+
+		if ($template === NULL) {
+			return FALSE;
+		}
+
 		$emailView->setTemplateSource($template->getContent());
 		$emailView->assignMultiple($this->markers);
 		$emailBody = $emailView->render();
@@ -214,6 +221,8 @@ class MailTemplateService {
 		} else {
 			$this->addMailToMailQueue($emailBody);
 		}
+
+		return TRUE;
 	}
 
 	/**