public function testAttachFiles()
 {
     $email = new Email();
     $email->attachFileFromString('foo bar', 'foo.txt', 'text/plain');
     $email->attachFile(__DIR__ . '/fixtures/attachment.txt', null, 'text/plain');
     $this->assertEquals(array('contents' => 'foo bar', 'filename' => 'foo.txt', 'mimetype' => 'text/plain'), $email->attachments[0], 'File is attached correctly from string');
     $this->assertEquals(array('contents' => 'Hello, I\'m a text document.', 'filename' => 'attachment.txt', 'mimetype' => 'text/plain'), $email->attachments[1], 'File is attached correctly from file');
 }