Message::getPriority return type fix (#87)

Author: bretislavstepan

src/Mail/Message.php

@@ -189,7 +189,8 @@ public function setPriority(int $priority)
 	 */
 	public function getPriority(): ?int
 	{
-		return $this->getHeader('X-Priority');
+		$priority = $this->getHeader('X-Priority');
+		return is_numeric($priority) ? (int) $priority : null;
 	}
 
 

tests/Mail/Mail.priority.phpt

@@ -0,0 +1,22 @@
+<?php
+
+/**
+ * Test: Nette\Mail\Message - Priority.
+ */
+
+declare(strict_types=1);
+
+use Nette\Mail\Message;
+use Tester\Assert;
+
+
+require __DIR__ . '/../bootstrap.php';
+
+
+$mail = new Message;
+
+Assert::null($mail->getPriority());
+
+$mail->setPriority(2);
+
+Assert::same(2, $mail->getPriority());