Add `ModelMetadata.ElementMetadata`

- #2664
- use new property to correctly determine `isTargetEnum` in `GetCurrentValues()`
 - avoid `ArgumentNullException` in all cases where raw values are `enum` but target is not
- stop skipping tests blocked by #2664, exposing a couple more #1487 issues
- use new property instead of private `GetElementType()` methods where possible
 - cleans up some duplicate code
 - also remove redundant use of `IsCollectionType` and `ElementMetadata`

nits:
- move properties above methods in `ModelMetadata`
- avoid accidentally-incorrect "Remove Unnecessary Usings"

src/Microsoft.AspNet.Mvc.Abstractions/ModelBinding/ModelMetadata.cs

@@ -5,7 +5,9 @@ using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.ComponentModel;
+#if DNXCORE50
 using System.Reflection;
+#endif
 using Microsoft.AspNet.Mvc.ModelBinding.Metadata;
 using Microsoft.Framework.Internal;
 
@@ -79,7 +81,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         public abstract string BinderModelName { get; }
 
         /// <summary>
-        /// Gets the <see cref="Type"/> of an <see cref="IModelBinder"/> of a model if specified explicitly using 
+        /// Gets the <see cref="Type"/> of an <see cref="IModelBinder"/> of a model if specified explicitly using
         /// <see cref="IBinderTypeProviderMetadata"/>.
         /// </summary>
         public abstract Type BinderType { get; }
@@ -124,6 +126,18 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         /// </summary>
         public abstract string EditFormatString { get; }
 
+        /// <summary>
+        /// Gets the <see cref="ModelMetadata"/> for elements of <see cref="ModelType"/> if that <see cref="Type"/>
+        /// implements <see cref="IEnumerable"/>.
+        /// </summary>
+        /// <value>
+        /// <see cref="ModelMetadata"/> for <c>T</c> if <see cref="ModelType"/> implements
+        /// <see cref="IEnumerable{T}"/>. <see cref="ModelMetadata"/> for <c>object</c> if <see cref="ModelType"/>
+        /// implements <see cref="IEnumerable"/> but not <see cref="IEnumerable{T}"/>. <c>null</c> otherwise i.e. when
+        /// <see cref="IsCollectionType"/> is <c>false</c>.
+        /// </value>
+        public abstract ModelMetadata ElementMetadata { get; }
+
         /// <summary>
         /// Gets the ordered display names and values of all <see cref="Enum"/> values in <see cref="ModelType"/> or
         /// <c>Nullable.GetUnderlyingType(ModelType)</c>.
@@ -329,6 +343,16 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
             }
         }
 
+        /// <summary>
+        /// Gets a property getter delegate to get the property value from a model object.
+        /// </summary>
+        public abstract Func<object, object> PropertyGetter { get; }
+
+        /// <summary>
+        /// Gets a property setter delegate to set the property value on a model object.
+        /// </summary>
+        public abstract Action<object, object> PropertySetter { get; }
+
         /// <summary>
         /// Gets a display name for the model.
         /// </summary>
@@ -341,15 +365,5 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         {
             return DisplayName ?? PropertyName ?? ModelType.Name;
         }
-
-        /// <summary>
-        /// Gets or sets a property getter delegate to get the property value from a model object.
-        /// </summary>
-        public abstract Func<object, object> PropertyGetter { get; }
-
-        /// <summary>
-        /// Gets or sets a property setter delegate to set the property value on a model object.
-        /// </summary>
-        public abstract Action<object, object> PropertySetter { get; }
     }
 }

src/Microsoft.AspNet.Mvc.Core/ModelBinding/Metadata/DefaultModelMetadata.cs

@@ -2,9 +2,14 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
+using System.Diagnostics;
 using System.Linq;
+#if DNXCORE50
+using System.Reflection;
+#endif
 using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Mvc.ModelBinding.Metadata
@@ -19,6 +24,8 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Metadata
         private readonly DefaultMetadataDetails _details;
 
         private ReadOnlyDictionary<object, object> _additionalValues;
+        private ModelMetadata _elementMetadata;
+        private bool _haveCalculatedElementMetadata;
         private bool? _isReadOnly;
         private bool? _isRequired;
         private ModelPropertyCollection _properties;
@@ -220,6 +227,49 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Metadata
             }
         }
 
+        /// <inheritdoc />
+        public override ModelMetadata ElementMetadata
+        {
+            get
+            {
+                if (!_haveCalculatedElementMetadata)
+                {
+                    _haveCalculatedElementMetadata = true;
+                    if (!IsCollectionType)
+                    {
+                        // Short-circuit checks below. If not IsCollectionType, ElementMetadata is null.
+                        // For example, as in IsCollectionType, do not consider strings collections.
+                        return null;
+                    }
+
+                    Type elementType = null;
+                    if (ModelType.IsArray)
+                    {
+                        elementType = ModelType.GetElementType();
+                    }
+                    else
+                    {
+                        elementType = ClosedGenericMatcher.ExtractGenericInterface(ModelType, typeof(IEnumerable<>))
+                            ?.GenericTypeArguments[0];
+                        if (elementType == null && typeof(IEnumerable).IsAssignableFrom(ModelType))
+                        {
+                            // ModelType implements IEnumerable but not IEnumerable<T>.
+                            elementType = typeof(object);
+                        }
+                    }
+
+                    Debug.Assert(
+                        elementType != null,
+                        $"Unable to find element type for '{ ModelType.FullName }' though IsCollectionType is true.");
+
+                    // Success
+                    _elementMetadata = _provider.GetMetadataForType(elementType);
+                }
+
+                return _elementMetadata;
+            }
+        }
+
         /// <inheritdoc />
         public override IEnumerable<KeyValuePair<string, string>> EnumDisplayNamesAndValues
         {

src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/DefaultObjectValidator.cs

@@ -169,11 +169,9 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
             ExpandValidationNode(validationContext, modelExplorer);
 
             IList<IModelValidator> validators = null;
-            if (modelExplorer.Metadata.IsCollectionType && modelExplorer.Model != null)
+            var elementMetadata = modelExplorer.Metadata.ElementMetadata;
+            if (elementMetadata != null)
             {
-                var enumerableModel = (IEnumerable)modelExplorer.Model;
-                var elementType = GetElementType(enumerableModel.GetType());
-                var elementMetadata = _modelMetadataProvider.GetMetadataForType(elementType);
                 validators = GetValidators(validationContext.ModelValidationContext.ValidatorProvider, elementMetadata);
             }
 
@@ -283,7 +281,8 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
                 return;
             }
 
-            if (!modelExplorer.Metadata.IsCollectionType)
+            var elementMetadata = modelExplorer.Metadata.ElementMetadata;
+            if (elementMetadata == null)
             {
                 foreach (var property in validationNode.ModelMetadata.Properties)
                 {
@@ -300,8 +299,6 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
             else
             {
                 var enumerableModel = (IEnumerable)modelExplorer.Model;
-                var elementType = GetElementType(enumerableModel.GetType());
-                var elementMetadata = _modelMetadataProvider.GetMetadataForType(elementType);
 
                 // An integer index is incorrect in scenarios where there is a custom index provided by the user.
                 // However those scenarios are supported by createing a ModelValidationNode with the right keys.
@@ -321,26 +318,6 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
             }
         }
 
-        private static Type GetElementType(Type type)
-        {
-            Debug.Assert(typeof(IEnumerable).GetTypeInfo().IsAssignableFrom(type.GetTypeInfo()));
-            if (type.IsArray)
-            {
-                return type.GetElementType();
-            }
-
-            foreach (var implementedInterface in type.GetInterfaces())
-            {
-                if (implementedInterface.GetTypeInfo().IsGenericType &&
-                    implementedInterface.GetGenericTypeDefinition() == typeof(IEnumerable<>))
-                {
-                    return implementedInterface.GetGenericArguments()[0];
-                }
-            }
-
-            return typeof(object);
-        }
-
         private class ValidationContext
         {
             public ModelValidationContext ModelValidationContext { get; set; }

src/Microsoft.AspNet.Mvc.Core/ModelBindingHelper.cs

@@ -369,7 +369,7 @@ namespace Microsoft.AspNet.Mvc
         /// <param name="expressions">Expressions identifying the properties to allow for binding.</param>
         /// <returns>An expression which can be used with <see cref="IPropertyBindingPredicateProvider"/>.</returns>
         public static Expression<Func<ModelBindingContext, string, bool>> GetIncludePredicateExpression<TModel>(
-            string prefix, 
+            string prefix,
             Expression<Func<TModel, object>>[] expressions)
         {
             if (expressions.Length == 0)
@@ -417,15 +417,15 @@ namespace Microsoft.AspNet.Mvc
         {
             // If modelkey is empty, we need to iterate through properties (obtained from ModelMetadata) and
             // clear validation state for all entries in ModelStateDictionary that start with each property name.
-            // If modelkey is non-empty, clear validation state for all entries in ModelStateDictionary 
+            // If modelkey is non-empty, clear validation state for all entries in ModelStateDictionary
             // that start with modelKey
             if (string.IsNullOrEmpty(modelKey))
             {
                 var modelMetadata = metadataProvider.GetMetadataForType(modelType);
-                if (modelMetadata.IsCollectionType)
+                var elementMetadata = modelMetadata.ElementMetadata;
+                if (elementMetadata != null)
                 {
-                    var elementType = GetElementType(modelMetadata.ModelType);
+                    modelMetadata = elementMetadata;
-                    modelMetadata = metadataProvider.GetMetadataForType(elementType);
                 }
 
                 foreach (var property in modelMetadata.Properties)
@@ -440,27 +440,6 @@ namespace Microsoft.AspNet.Mvc
             }
         }
 
-        private static Type GetElementType(Type type)
-        {
-            Debug.Assert(typeof(IEnumerable).GetTypeInfo().IsAssignableFrom(type.GetTypeInfo()));
-            if (type.IsArray)
-            {
-                return type.GetElementType();
-            }
-
-            foreach (var implementedInterface in type.GetInterfaces())
-            {
-                if (implementedInterface.GetTypeInfo().IsGenericType &&
-                    implementedInterface.GetGenericTypeDefinition() == typeof(IEnumerable<>))
-                {
-                    return implementedInterface.GetGenericArguments()[0];
-                }
-            }
-
-            return typeof(object);
-        }
-
-
         internal static void ValidateBindingContext([NotNull] ModelBindingContext bindingContext)
         {
             if (bindingContext.ModelMetadata == null)

src/Microsoft.AspNet.Mvc.Extensions/Rendering/Html/DefaultDisplayTemplates.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Globalization;
 using System.Text;
 using Microsoft.AspNet.Mvc.Extensions;
@@ -106,40 +107,42 @@ namespace Microsoft.AspNet.Mvc.Rendering
                     "Collection", model.GetType().FullName, typeof(IEnumerable).FullName));
             }
 
-            var typeInCollection = typeof(string);
+            var elementMetadata = htmlHelper.ViewData.ModelMetadata.ElementMetadata;
-            var genericEnumerableType = ClosedGenericMatcher.ExtractGenericInterface(
+            Debug.Assert(elementMetadata != null);
-                collection.GetType(),
+            var typeInCollectionIsNullableValueType = elementMetadata.IsNullableValueType;
-                typeof(IEnumerable<>));
+
-            if (genericEnumerableType != null)
+            var serviceProvider = htmlHelper.ViewContext.HttpContext.RequestServices;
+            var metadataProvider = serviceProvider.GetRequiredService<IModelMetadataProvider>();
+
+            // Use typeof(string) instead of typeof(object) for IEnumerable collections. Neither type is Nullable<T>.
+            if (elementMetadata.ModelType == typeof(object))
             {
-                typeInCollection = genericEnumerableType.GenericTypeArguments[0];
+                elementMetadata = metadataProvider.GetMetadataForType(typeof(string));
             }
 
-            var typeInCollectionIsNullableValueType = TypeHelper.IsNullableValueType(typeInCollection);
-
             var oldPrefix = htmlHelper.ViewData.TemplateInfo.HtmlFieldPrefix;
-
             try
             {
                 htmlHelper.ViewData.TemplateInfo.HtmlFieldPrefix = string.Empty;
 
                 var fieldNameBase = oldPrefix;
                 var result = new StringBuilder();
-
-                var serviceProvider = htmlHelper.ViewContext.HttpContext.RequestServices;
-                var metadataProvider = serviceProvider.GetRequiredService<IModelMetadataProvider>();
                 var viewEngine = serviceProvider.GetRequiredService<ICompositeViewEngine>();
 
                 var index = 0;
                 foreach (var item in collection)
                 {
-                    var itemType = typeInCollection;
+                    var itemMetadata = elementMetadata;
                     if (item != null && !typeInCollectionIsNullableValueType)
                     {
-                        itemType = item.GetType();
+                        itemMetadata = metadataProvider.GetMetadataForType(item.GetType());
                     }
 
-                    var modelExplorer = metadataProvider.GetModelExplorerForType(itemType, item);
+                    var modelExplorer = new ModelExplorer(
+                        metadataProvider,
+                        container: htmlHelper.ViewData.ModelExplorer,
+                        metadata: itemMetadata,
+                        model: item);
                     var fieldName = string.Format(CultureInfo.InvariantCulture, "{0}[{1}]", fieldNameBase, index++);
 
                     var templateBuilder = new TemplateBuilder(

src/Microsoft.AspNet.Mvc.Extensions/Rendering/Html/DefaultEditorTemplates.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Globalization;
 using System.Text;
 using Microsoft.AspNet.Mvc.Extensions;
@@ -67,39 +68,42 @@ namespace Microsoft.AspNet.Mvc.Rendering
                     "Collection", model.GetType().FullName, typeof(IEnumerable).FullName));
             }
 
-            var typeInCollection = typeof(string);
+            var elementMetadata = htmlHelper.ViewData.ModelMetadata.ElementMetadata;
-            var genericEnumerableType = ClosedGenericMatcher.ExtractGenericInterface(
+            Debug.Assert(elementMetadata != null);
-                collection.GetType(),
+            var typeInCollectionIsNullableValueType = elementMetadata.IsNullableValueType;
-                typeof(IEnumerable<>));
+
-            if (genericEnumerableType != null)
+            var serviceProvider = htmlHelper.ViewContext.HttpContext.RequestServices;
+            var metadataProvider = serviceProvider.GetRequiredService<IModelMetadataProvider>();
+
+            // Use typeof(string) instead of typeof(object) for IEnumerable collections. Neither type is Nullable<T>.
+            if (elementMetadata.ModelType == typeof(object))
             {
-                typeInCollection = genericEnumerableType.GenericTypeArguments[0];
+                elementMetadata = metadataProvider.GetMetadataForType(typeof(string));
             }
 
-            var typeInCollectionIsNullableValueType = TypeHelper.IsNullableValueType(typeInCollection);
             var oldPrefix = viewData.TemplateInfo.HtmlFieldPrefix;
-
             try
             {
                 viewData.TemplateInfo.HtmlFieldPrefix = string.Empty;
 
                 var fieldNameBase = oldPrefix;
                 var result = new StringBuilder();
-
-                var serviceProvider = htmlHelper.ViewContext.HttpContext.RequestServices;
-                var metadataProvider = serviceProvider.GetRequiredService<IModelMetadataProvider>();
                 var viewEngine = serviceProvider.GetRequiredService<ICompositeViewEngine>();
 
                 var index = 0;
                 foreach (var item in collection)
                 {
-                    var itemType = typeInCollection;
+                    var itemMetadata = elementMetadata;
                     if (item != null && !typeInCollectionIsNullableValueType)
                     {
-                        itemType = item.GetType();
+                        itemMetadata = metadataProvider.GetMetadataForType(item.GetType());
                     }
 
-                    var modelExplorer = metadataProvider.GetModelExplorerForType(itemType, item);
+                    var modelExplorer = new ModelExplorer(
+                        metadataProvider,
+                        container: htmlHelper.ViewData.ModelExplorer,
+                        metadata: itemMetadata,
+                        model: item);
                     var fieldName = string.Format(CultureInfo.InvariantCulture, "{0}[{1}]", fieldNameBase, index++);
 
                     var templateBuilder = new TemplateBuilder(

src/Microsoft.AspNet.Mvc.Extensions/Rendering/Html/DefaultHtmlGenerator.cs

@@ -34,7 +34,7 @@ namespace Microsoft.AspNet.Mvc.Rendering
         /// <summary>
         /// Initializes a new instance of the <see cref="DefaultHtmlGenerator"/> class.
         /// </summary>
-        /// <param name="antiForgery">The <see cref="AntiForgery"/> instance which is used to generate anti-forgery 
+        /// <param name="antiForgery">The <see cref="AntiForgery"/> instance which is used to generate anti-forgery
         /// tokens.</param>
         /// <param name="optionsAccessor">The accessor for <see cref="MvcOptions"/>.</param>
         /// <param name="metadataProvider">The <see cref="IModelMetadataProvider"/>.</param>
@@ -796,11 +796,19 @@ namespace Microsoft.AspNet.Mvc.Rendering
 
             modelExplorer = modelExplorer ??
                 ExpressionMetadataProvider.FromStringExpression(expression, viewContext.ViewData, _metadataProvider);
+            var metadata = modelExplorer.Metadata;
+            if (allowMultiple && metadata.IsCollectionType)
+            {
+                metadata = metadata.ElementMetadata;
+            }
 
-            var enumNames = modelExplorer.Metadata.EnumNamesAndValues;
+            var enumNames = metadata.EnumNamesAndValues;
-            var isTargetEnum = modelExplorer.Metadata.IsEnum;
+            var isTargetEnum = metadata.IsEnum;
-            var innerType =
+
-                Nullable.GetUnderlyingType(modelExplorer.Metadata.ModelType) ?? modelExplorer.Metadata.ModelType;
+            // Logic below assumes isTargetEnum and enumNames are consistent. Confirm that expectation is met.
+            Debug.Assert(isTargetEnum ^ enumNames == null);
+
+            var innerType = Nullable.GetUnderlyingType(metadata.ModelType) ?? metadata.ModelType;
 
             // Convert raw value collection to strings.
             var currentValues = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
@@ -841,13 +849,18 @@ namespace Microsoft.AspNet.Mvc.Rendering
                     var integerString = enumValue.ToString("d");
                     currentValues.Add(integerString);
 
-                    // Add all simple names for this value.
+                    // isTargetEnum may be false when raw value has a different type than the target e.g. ViewData
-                    var matchingNames = enumNames
+                    // contains enum values and property has type int or string.
-                        .Where(kvp => string.Equals(integerString, kvp.Value, StringComparison.Ordinal))
+                    if (isTargetEnum)
-                        .Select(kvp => kvp.Key);
-                    foreach (var name in matchingNames)
                     {
-                        currentValues.Add(name);
+                        // Add all simple names for this value.
+                        var matchingNames = enumNames
+                            .Where(kvp => string.Equals(integerString, kvp.Value, StringComparison.Ordinal))
+                            .Select(kvp => kvp.Key);
+                        foreach (var name in matchingNames)
+                        {
+                            currentValues.Add(name);
+                        }
                     }
                 }
             }

test/Microsoft.AspNet.Mvc.Abstractions.Test/ModelBinding/ModelMetadataTest.cs

@@ -269,6 +269,14 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 }
             }
 
+            public override ModelMetadata ElementMetadata
+            {
+                get
+                {
+                    throw new NotImplementedException();
+                }
+            }
+
             public override IEnumerable<KeyValuePair<string, string>> EnumDisplayNamesAndValues
             {
                 get

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/Metadata/DefaultModelMetadataTest.cs

@@ -2,7 +2,9 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Collections;
 using System.Collections.Generic;
+using System.Collections.ObjectModel;
 using System.Linq;
 #if !DNXCORE50
 using Moq;
@@ -52,6 +54,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Metadata
             Assert.Null(metadata.DisplayFormatString);
             Assert.Null(metadata.DisplayName);
             Assert.Null(metadata.EditFormatString);
+            Assert.Null(metadata.ElementMetadata);
             Assert.Null(metadata.EnumDisplayNamesAndValues);
             Assert.Null(metadata.EnumNamesAndValues);
             Assert.Null(metadata.NullDisplayText);
@@ -106,6 +109,69 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Metadata
             Assert.Equal(typeof(Exception), metadata.ContainerType);
         }
 
+        [Theory]
+        [InlineData(typeof(object))]
+        [InlineData(typeof(int))]
+        [InlineData(typeof(NonCollectionType))]
+        [InlineData(typeof(string))]
+        public void ElementMetadata_ReturnsNull_ForNonCollections(Type modelType)
+        {
+            // Arrange
+            var provider = new EmptyModelMetadataProvider();
+            var detailsProvider = new EmptyCompositeMetadataDetailsProvider();
+
+            var key = ModelMetadataIdentity.ForType(modelType);
+            var cache = new DefaultMetadataDetails(key, new ModelAttributes(new object[0]));
+
+            var metadata = new DefaultModelMetadata(provider, detailsProvider, cache);
+
+            // Act
+            var elementMetadata = metadata.ElementMetadata;
+
+            // Assert
+            Assert.Null(elementMetadata);
+        }
+
+        [Theory]
+        [InlineData(typeof(int[]), typeof(int))]
+        [InlineData(typeof(List<string>), typeof(string))]
+        [InlineData(typeof(DerivedList), typeof(int))]
+        [InlineData(typeof(IEnumerable), typeof(object))]
+        [InlineData(typeof(IEnumerable<string>), typeof(string))]
+        [InlineData(typeof(Collection<int>), typeof(int))]
+        [InlineData(typeof(Dictionary<object, object>), typeof(KeyValuePair<object, object>))]
+        [InlineData(typeof(DerivedDictionary), typeof(KeyValuePair<string, int>))]
+        public void ElementMetadata_ReturnsExpectedMetadata(Type modelType, Type elementType)
+        {
+            // Arrange
+            var provider = new EmptyModelMetadataProvider();
+            var detailsProvider = new EmptyCompositeMetadataDetailsProvider();
+
+            var key = ModelMetadataIdentity.ForType(modelType);
+            var cache = new DefaultMetadataDetails(key, new ModelAttributes(new object[0]));
+
+            var metadata = new DefaultModelMetadata(provider, detailsProvider, cache);
+
+            // Act
+            var elementMetadata = metadata.ElementMetadata;
+
+            // Assert
+            Assert.NotNull(elementMetadata);
+            Assert.Equal(elementType, elementMetadata.ModelType);
+        }
+
+        private class NonCollectionType
+        {
+        }
+
+        private class DerivedList : List<int>
+        {
+        }
+
+        private class DerivedDictionary : Dictionary<string, int>
+        {
+        }
+
         [Theory]
         [InlineData(typeof(string))]
         [InlineData(typeof(IDisposable))]
@@ -160,7 +226,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Metadata
             var expectedProperties = new DefaultModelMetadata[]
             {
                 new DefaultModelMetadata(
-                    provider.Object, 
+                    provider.Object,
                     detailsProvider,
                     new DefaultMetadataDetails(
                         ModelMetadataIdentity.ForProperty(typeof(int), "Prop1", typeof(string)),

test/Microsoft.AspNet.Mvc.Extensions.Test/Rendering/HtmlHelperSelectTest.cs

@@ -874,7 +874,7 @@ namespace Microsoft.AspNet.Mvc.Rendering
             Assert.Equal(expectedHtml, html.ToString());
         }
 
-        [Fact(Skip = "#2664, throws ArgumentNullException")]
+        [Fact]
         public void ListBoxNotInTemplate_GetsViewDataEntry_IfModelStateEmpty()
         {
             // Arrange
@@ -899,7 +899,7 @@ namespace Microsoft.AspNet.Mvc.Rendering
             Assert.Equal(expectedHtml, html.ToString());
         }
 
-        [Fact(Skip = "#2664, throws ArgumentNullException")]
+        [Fact(Skip = "#1487, incorrectly matches Property1 entry (without prefix) in ViewData.")]
         public void ListBoxInTemplate_GetsViewDataEntry_IfModelStateEmpty()
         {
             // Arrange
@@ -927,7 +927,7 @@ namespace Microsoft.AspNet.Mvc.Rendering
             Assert.Equal(expectedHtml, html.ToString());
         }
 
-        [Fact(Skip = "#2664, throws ArgumentNullException")]
+        [Fact(Skip = "#1487, incorrectly matches Property1 entry (without prefix) in ViewData.")]
         public void ListBoxInTemplate_GetsPropertyOfViewDataEntry_IfModelStateEmptyAndNoViewDataEntryWithPrefix()
         {
             // Arrange
@@ -954,7 +954,7 @@ namespace Microsoft.AspNet.Mvc.Rendering
             Assert.Equal(expectedHtml, html.ToString());
         }
 
-        [Fact(Skip = "#2664, throws ArgumentNullException")]
+        [Fact]
         public void ListBoxNotInTemplate_GetsPropertyOfModel_IfModelStateAndViewDataEmpty()
         {
             // Arrange
@@ -970,7 +970,7 @@ namespace Microsoft.AspNet.Mvc.Rendering
             Assert.Equal(expectedHtml, html.ToString());
         }
 
-        [Fact(Skip = "#2664, throws ArgumentNullException")]
+        [Fact]
         public void ListBoxInTemplate_GetsPropertyOfModel_IfModelStateAndViewDataEmpty()
         {
             // Arrange