public function testSerializeMessage()
{
$message = $this->getMock(Message::CLASS);
$config = new Configuration();
$serializer = new MessageSerializer($config);
$stream = Stream::create();
$message->expects($this->once())->method('toStream')->willReturn($stream)->with($this->equalTo($config));
$this->assertInstanceOf('Protobuf\\Serializer', $serializer);
$this->assertSame($stream, $serializer->serialize($message));
}