public void processing_an_add_commentary_message_adds_it_to_the_commentary_property()
{
var commentary1 = "commentary1";
var commentary2 = "commentary2";
var expectedCommentary = commentary1 + commentary2;
var model = CreateModel(
new AddCommentaryMessage(commentary1),
new AddCommentaryMessage(commentary2));
Assert.Equal(expectedCommentary, model.Commentary);
}