public void Handle_InnerIsCalled()
{
IRequestHandler <Request, string> inner = Substitute.For <IRequestHandler <Request, string> >();
var logger = Substitute.For <ILogger>();
var handler = new LoggingHandler <Request, string>(inner, logger);
handler.Handle(new Request());
logger.Received().Information(Arg.Is <string>(s => s.Contains("Logging:")));
inner.Received().Handle(Arg.Any <Request>());
}