public void send_simple_message()
{
var buf = new SocketBufferFake();
var expected = "Hello world!";
var sut = new StringEncoder();
sut.Prepare(expected);
sut.Send(buf);
BitConverter.ToInt32(buf.Buffer, 0).Should().Be(expected.Length);
var actual = Encoding.UTF8.GetString(buf.Buffer, buf.BaseOffset + 4, buf.Count - 4);
actual.Should().Be(expected);
}