public void PostsToTheCorrectUrl()
{
var connection = Substitute.For <IApiConnection>();
var client = new GistsClient(connection);
var newGist = new NewGist();
newGist.Description = "my new gist";
newGist.Public = true;
newGist.Files.Add("myGistTestFile.cs", "new GistsClient(connection).Create();");
client.Create(newGist);
connection.Received().Post <Gist>(Arg.Is <Uri>(u => u.ToString() == "gists"), Arg.Any <object>());
}