public void EnumerateElements_TwoEnumerableImplementations()
        {
            // Arrange
            var model = new TwiceEnumerable(new int[] { 2, 3, 5 });

            var metadata = TestModelMetadataProvider.CreateDefaultProvider().GetMetadataForType(typeof(TwiceEnumerable));
            var strategy = new ExplicitIndexCollectionValidationStrategy(new string[] { "zero", "one", "two" });

            // Act
            var enumerator = strategy.GetChildren(metadata, "prefix", model);

            // Assert
            Assert.Collection(
                BufferEntries(enumerator).OrderBy(e => e.Key),
                e =>
            {
                Assert.Equal("prefix[one]", e.Key);
                Assert.Equal(3, e.Model);
                Assert.Same(metadata.ElementMetadata, e.Metadata);
            },
                e =>
            {
                Assert.Equal("prefix[two]", e.Key);
                Assert.Equal(5, e.Model);
                Assert.Same(metadata.ElementMetadata, e.Metadata);
            },
                e =>
            {
                Assert.Equal("prefix[zero]", e.Key);
                Assert.Equal(2, e.Model);
                Assert.Same(metadata.ElementMetadata, e.Metadata);
            });
        }
        public void EnumerateElements_Dictionary()
        {
            // Arrange
            var model = new Dictionary <int, string>()
            {
                { 2, "two" },
                { 3, "three" },
                { 5, "five" },
            };

            var metadata = TestModelMetadataProvider.CreateDefaultProvider().GetMetadataForType(typeof(List <int>));
            var strategy = new ExplicitIndexCollectionValidationStrategy(new string[] { "zero", "one", "two" });

            // Act
            var enumerator = strategy.GetChildren(metadata, "prefix", model);

            // Assert
            Assert.Collection(
                BufferEntries(enumerator).OrderBy(e => e.Key),
                e =>
            {
                Assert.Equal("prefix[one]", e.Key);
                Assert.Equal(new KeyValuePair <int, string>(3, "three"), e.Model);
                Assert.Same(metadata.ElementMetadata, e.Metadata);
            },
                e =>
            {
                Assert.Equal("prefix[two]", e.Key);
                Assert.Equal(new KeyValuePair <int, string>(5, "five"), e.Model);
                Assert.Same(metadata.ElementMetadata, e.Metadata);
            },
                e =>
            {
                Assert.Equal("prefix[zero]", e.Key);
                Assert.Equal(new KeyValuePair <int, string>(2, "two"), e.Model);
                Assert.Same(metadata.ElementMetadata, e.Metadata);
            });
        }