add test

tests/DatabaseHandlerTest.php

@@ -45,7 +45,7 @@ public function testPriority()
         $this->assertSame('high', self::getPrivateProperty($handler, 'priority'));
     }
 
-    public function testPriorityException()
+    public function testPriorityNameException()
     {
         $this->expectException(QueueException::class);
         $this->expectExceptionMessage('The priority name should consists only lowercase letters.');
@@ -54,6 +54,15 @@ public function testPriorityException()
         $handler->setPriority('high_:');
     }
 
+    public function testPriorityNameLengthException()
+    {
+        $this->expectException(QueueException::class);
+        $this->expectExceptionMessage('The priority name is too long. It should be no longer than 64 letters.');
+
+        $handler = new DatabaseHandler($this->config);
+        $handler->setPriority(str_repeat('a', 65));
+    }
+
     /**
      * @throws ReflectionException
      */