fix for scrutinizer

.github/workflows/pull-request-checks.yaml

@@ -30,12 +30,13 @@ jobs:
       - name: Run Composer linter
         run: composer validate --strict --no-check-lock
 
+      - name: Run PHP unit test suite
+        run: composer run-script test
+
       - name: Run phpstan
         run: composer run-script phpstan
 
       - name: Run lint PHP
         run: composer run-script php-lint
 
-      # Tests
-      - name: Run PHP unit test suite
-        run: composer run-script test
+

src/Email/MessageOptions.php

@@ -42,8 +42,12 @@ public function __construct(
         $this->participants = $participants;
     }
 
-    public function getSubject(): ?string
+    public function getSubject(): string
     {
+        if (!\is_string($this->subject)) {
+            throw new InvalidArgumentException('Invalid subject');
+        }
+
         return $this->subject;
     }
 

src/Email/Participants.php

@@ -59,8 +59,12 @@ public function __construct(
         $this->bcc = $bcc;
     }
 
-    public function getSender(): ?Address
+    public function getSender(): Address
     {
+        if (!$this->sender instanceof Address) {
+            throw new InvalidArgumentException('Invalid sender');
+        }
+
         return $this->sender;
     }
 

src/Exception/ExceptionInterface.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FH\Bundle\MailerBundle\Exception;
+
+interface ExceptionInterface
+{
+}

src/Exception/InvalidArgumentException.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FH\Bundle\MailerBundle\Exception;
+
+use InvalidArgumentException as InvalidArgumentExceptionAlias;
+
+class InvalidArgumentException extends InvalidArgumentExceptionAlias implements ExceptionInterface
+{
+}