public void ReturnsNull_WhenAskingForUnregisteredCommandHandler()
        {
            var testee = new CommandHandlerRegistry();

            var handler = testee.GetCommandHandler(new ValueCommand(11));

            handler.Should().BeNull();
        }
        public void CanGetRegisteredCommandHandler()
        {
            var testee = new CommandHandlerRegistry();

            testee.Register(typeof(ValueCommandHandler), typeof(ValueCommand));

            var handler = testee.GetCommandHandler(new ValueCommand(11));

            handler.Should().BeAssignableTo <ValueCommandHandler>();
        }