class PhpMailTest

class PhpMailTest extends UnitTestCase {
    
    /**
     * The configuration factory.
     *
     * @var \Drupal\Core\Config\ConfigFactoryInterface|\PHPUnit\Framework\MockObject\MockObject
     */
    protected $configFactory;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        parent::setUp();
        // Use the provided config for system.mail.interface settings.
        $this->configFactory = $this->getConfigFactoryStub([
            'system.mail' => [
                'interface' => [],
            ],
            'system.site' => [
                'mail' => 'test@example.com',
            ],
        ]);
        $container = new ContainerBuilder();
        $container->set('config.factory', $this->configFactory);
        \Drupal::setContainer($container);
    }
    
    /**
     * Creates a mocked PhpMail object.
     *
     * The method "doMail()" gets overridden to avoid a mail() call in tests.
     *
     * @return \Drupal\Core\Mail\Plugin\Mail\PhpMail|\PHPUnit\Framework\MockObject\MockObject
     *   A PhpMail instance.
     */
    protected function createPhpMailInstance() : PhpMail {
        $mailer = $this->getMockBuilder(PhpMail::class)
            ->onlyMethods([
            'doMail',
        ])
            ->getMock();
        return $mailer;
    }
    
    /**
     * Tests sending a mail using a From address with a comma in it.
     *
     * @covers ::testMail
     */
    public function testMail() {
        // Setup a mail message.
        $message = [
            'id' => 'example_key',
            'module' => 'example',
            'key' => 'key',
            'to' => 'to@example.org',
            'from' => 'from@example.org',
            'reply-to' => 'from@example.org',
            'langcode' => 'en',
            'params' => [],
            'send' => TRUE,
            'subject' => "test\r\nsubject",
            'body' => '',
            'headers' => [
                'MIME-Version' => '1.0',
                'Content-Type' => 'text/plain; charset=UTF-8; format=flowed; delsp=yes',
                'Content-Transfer-Encoding' => '8Bit',
                'X-Mailer' => 'Drupal',
                'From' => '"Foo, Bar, and Baz" <from@example.org>',
                'Reply-to' => 'from@example.org',
                'Return-Path' => 'from@example.org',
            ],
        ];
        $mailer = $this->createPhpMailInstance();
        // Verify we use line endings consistent with the PHP mail() function, which
        // changed with PHP 8. See:
        // - https://www.drupal.org/node/3270647
        // - https://bugs.php.net/bug.php?id=81158
        // Since Drupal 10+ does not support PHP < 8, the PHP version check in the next line can be removed in Drupal 10+.
        $line_end = PHP_MAJOR_VERSION < 8 ? "\n" : "\r\n";
        $expected_headers = "MIME-Version: 1.0{$line_end}";
        $expected_headers .= "Content-Type: text/plain; charset=UTF-8; format=flowed; delsp=yes{$line_end}";
        $expected_headers .= "Content-Transfer-Encoding: 8Bit{$line_end}";
        $expected_headers .= "X-Mailer: Drupal{$line_end}";
        $expected_headers .= "From: \"Foo, Bar, and Baz\" <from@example.org>{$line_end}";
        $expected_headers .= "Reply-to: from@example.org{$line_end}";
        $mailer->expects($this->once())
            ->method('doMail')
            ->with($this->equalTo('to@example.org'), $this->equalTo("=?utf-8?Q?test?={$line_end} =?utf-8?Q?subject?="), $this->equalTo(''), $this->stringStartsWith($expected_headers))
            ->willReturn(TRUE);
        $this->assertTrue($mailer->mail($message));
    }

}