public void Feature_observable_returns_feature_from_object_ctor()
        {
            var feature = new Feature<string>((object) "hello");

            feature.Subscribe(v => { });

            Assert.That(feature.First(), Is.EqualTo("hello"));
        }
        public void After_it_is_subscribed_a_Feature_is_available_if_an_initialization_function_is_supplied()
        {
            var feature = new Feature<string>(() => "hello");

            feature.Subscribe(f => { });

            Assert.That(feature.Availability.First(), Is.True);
        }
        public void Feature_observable_returns_feature_from_object_ctor_when_passed_a_delegate()
        {
            Func<object> getter = () => "hello";
            var feature = new Feature<string>(getter);

            feature.Subscribe(v => { });

            Assert.That(feature.First(), Is.EqualTo("hello"));
        }
        public void A_feature_can_be_subscribed_before_it_is_registered_and_when_it_is_later_initialized_subscribers_will_be_notified()
        {
            string result = null;
            var feature = new Feature<string>();

            feature.Subscribe(s => result = s);

            Assert.That(result, Is.Null);

            feature.OnNext("hello");

            Assert.That(result, Is.EqualTo("hello"));
        }
        public void When_a_feature_fails_to_load_the_error_is_published_to_OnError_and_not_thrown()
        {
            var feature = new Feature<string>(() => { throw new ArgumentException("oops!"); });

            Exception error = null;
            string result = null;
            feature.Subscribe(f => result = f, ex => error = ex);

            Assert.That(result, Is.Null);
            Assert.That(error, Is.InstanceOf<ArgumentException>());
        }
        public void A_Feature_whose_instance_is_an_IFeature_produces_a_value_when_the_IFeature_is_available()
        {
            var inner = new Feature<string>();
            var outer = new Feature<Feature<string>>(inner);
            Feature<string> result = null;

            outer.Subscribe(v => result = v);

            inner.OnNext("hello");

            Assert.That(outer.Availability.First(), Is.EqualTo(true));
            Assert.That(outer.First().First(), Is.EqualTo("hello"));
        }