Webiny\Component\Mailer\Mailer::getMessage PHP Method

    public function getMessage($config = null)
    {
        if ($config && !$config instanceof ConfigObject) {
            $config = new ConfigObject($config);
        }
        return Loader::getMessage($this->mailerName, $config);
    }

 public function testSend()
 {
     $mailer = new Mailer();
     $message = $mailer->getMessage();
     $message->setTo(new Email('*****@*****.**', 'Webiny'))->setBody('Testing')->setSubject('PHPUnit test');
     $result = $mailer->send($message);
     $this->assertNotFalse($result);
     // this test might fail if sendmail is not configured
 }