Add FieldName to model binding context

Adds a new property, FieldName, to ModelBindingContext. The FieldName is
the name of whatever code-element is being bound, regardless of what
model-prefix is in use.

This is needed for cases like the Header model binder. We always want to
use the property/parameter name and we don't care about model prefixes.

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

@@ -2,7 +2,6 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using Microsoft.AspNet.Mvc.Abstractions;
 using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Mvc.ModelBinding
@@ -15,10 +14,6 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         private static readonly Func<ModelBindingContext, string, bool>
             _defaultPropertyFilter = (context, propertyName) => true;
 
-        private string _modelName;
-        private ModelStateDictionary _modelState;
-        private Func<ModelBindingContext, string, bool> _propertyFilter;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="ModelBindingContext"/> class.
         /// </summary>
@@ -27,67 +22,82 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         }
 
         /// <summary>
-        /// Constructs a new instance of the <see cref="ModelBindingContext"/> class using the
+        /// Creates a new <see cref="ModelBindingContext"/> for top-level model binding operation.
-        /// <paramref name="bindingContext" />.
         /// </summary>
-        /// <param name="bindingContext">Existing <see cref="ModelBindingContext"/>.</param>
+        /// <param name="operationBindingContext">
-        /// <param name="modelName">Model name of associated with the new <see cref="ModelBindingContext"/>.</param>
+        /// The <see cref="OperationBindingContext"/> associated with the binding operation.
-        /// <param name="modelMetadata">Model metadata of associated with the new <see cref="ModelBindingContext"/>.
         /// </param>
-        public static ModelBindingContext GetChildModelBindingContext(
-            [NotNull] ModelBindingContext bindingContext,
-            [NotNull] string modelName,
-            [NotNull] ModelMetadata modelMetadata)
-        {
-            var modelBindingContext = new ModelBindingContext
-            {
-                ModelName = modelName,
-                ModelMetadata = modelMetadata,
-
-                ModelState = bindingContext.ModelState,
-                ValueProvider = bindingContext.ValueProvider,
-                OperationBindingContext = bindingContext.OperationBindingContext,
-
-                BindingSource = modelMetadata.BindingSource,
-                BinderModelName = modelMetadata.BinderModelName,
-                BinderType = modelMetadata.BinderType,
-            };
-
-            return modelBindingContext;
-        }
-
-        /// <summary>
-        /// Constructs a new instance of <see cref="ModelBindingContext"/> from given <paramref name="metadata"/>
-        /// and <paramref name="bindingInfo"/>.
-        /// </summary>
         /// <param name="metadata"><see cref="ModelMetadata"/> associated with the model.</param>
         /// <param name="bindingInfo"><see cref="BindingInfo"/> associated with the model.</param>
-        /// <param name="modelName">An optional name of the model to be used.</param>
+        /// <param name="modelName">The name of the property or parameter being bound.</param>
         /// <returns>A new instance of <see cref="ModelBindingContext"/>.</returns>
-        public static ModelBindingContext GetModelBindingContext(
+        public static ModelBindingContext CreateBindingContext(
+            [NotNull] OperationBindingContext operationBindingContext,
+            [NotNull] ModelStateDictionary modelState,
             [NotNull] ModelMetadata metadata,
             BindingInfo bindingInfo,
-            string modelName)
+            [NotNull] string modelName)
         {
             var binderModelName = bindingInfo?.BinderModelName ?? metadata.BinderModelName;
             var propertyPredicateProvider =
                 bindingInfo?.PropertyBindingPredicateProvider ?? metadata.PropertyBindingPredicateProvider;
-            return new ModelBindingContext
+
+            return new ModelBindingContext()
             {
-                ModelMetadata = metadata,
-                BindingSource = bindingInfo?.BindingSource ?? metadata.BindingSource,
-                PropertyFilter = propertyPredicateProvider?.PropertyFilter,
-                BinderType = bindingInfo?.BinderType ?? metadata.BinderType,
                 BinderModelName = binderModelName,
-                ModelName = binderModelName ?? metadata.PropertyName ?? modelName,
+                BindingSource = bindingInfo?.BindingSource ?? metadata.BindingSource,
+                BinderType = bindingInfo?.BinderType ?? metadata.BinderType,
+                PropertyFilter = propertyPredicateProvider?.PropertyFilter,
+
+                // We only support fallback to empty prefix in cases where the model name is inferred from
+                // the parameter or property being bound.
                 FallbackToEmptyPrefix = binderModelName == null,
+
+                // Because this is the top-level context, FieldName and ModelName should be the same.
+                FieldName = binderModelName ?? modelName,
+                ModelName = binderModelName ?? modelName,
+
+                IsTopLevelObject = true,
+                ModelMetadata = metadata,
+                ModelState = modelState,
+                OperationBindingContext = operationBindingContext,
+                ValueProvider = operationBindingContext.ValueProvider,
+            };
+        }
+
+        public static ModelBindingContext CreateChildBindingContext(
+            [NotNull] ModelBindingContext parent,
+            [NotNull] ModelMetadata modelMetadata,
+            [NotNull] string fieldName,
+            [NotNull] string modelName,
+            object model)
+        {
+            return new ModelBindingContext()
+            {
+                ModelState = parent.ModelState,
+                OperationBindingContext = parent.OperationBindingContext,
+                ValueProvider = parent.ValueProvider,
+
+                Model = model,
+                ModelMetadata = modelMetadata,
+                ModelName = modelName,
+                FieldName = fieldName,
+                BinderModelName = modelMetadata.BinderModelName,
+                BinderType = modelMetadata.BinderType,
+                BindingSource = modelMetadata.BindingSource,
+                PropertyFilter = modelMetadata.PropertyBindingPredicateProvider?.PropertyFilter,
             };
         }
 
         /// <summary>
         /// Represents the <see cref="OperationBindingContext"/> associated with this context.
         /// </summary>
-        public OperationBindingContext OperationBindingContext { get; set; }
+        public OperationBindingContext OperationBindingContext { get; [param:NotNull] set; }
+
+        /// <summary>
+        /// Gets or sets the name of the current field being bound.
+        /// </summary>
+        public string FieldName { get; [param: NotNull] set; }
 
         /// <summary>
         /// Gets or sets the model value for the current operation.
@@ -101,41 +111,19 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         /// <summary>
         /// Gets or sets the metadata for the model associated with this context.
         /// </summary>
-        public ModelMetadata ModelMetadata { get; set; }
+        public ModelMetadata ModelMetadata { get; [param: NotNull] set; }
 
         /// <summary>
         /// Gets or sets the name of the model. This property is used as a key for looking up values in
         /// <see cref="IValueProvider"/> during model binding.
         /// </summary>
-        public string ModelName
+        public string ModelName { get; [param: NotNull] set; }
-        {
-            get
-            {
-                if (_modelName == null)
-                {
-                    _modelName = string.Empty;
-                }
-                return _modelName;
-            }
-            set { _modelName = value; }
-        }
 
         /// <summary>
         /// Gets or sets the <see cref="ModelStateDictionary"/> used to capture <see cref="ModelState"/> values
         /// for properties in the object graph of the model when binding.
         /// </summary>
-        public ModelStateDictionary ModelState
+        public ModelStateDictionary ModelState { get; [param: NotNull] set; }
-        {
-            get
-            {
-                if (_modelState == null)
-                {
-                    _modelState = new ModelStateDictionary();
-                }
-                return _modelState;
-            }
-            set { _modelState = value; }
-        }
 
         /// <summary>
         /// Gets the type of the model.
@@ -143,14 +131,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         /// <remarks>
         /// The <see cref="ModelMetadata"/> property must be set to access this property.
         /// </remarks>
-        public Type ModelType
+        public Type ModelType => ModelMetadata?.ModelType;
-        {
-            get
-            {
-                EnsureModelMetadata();
-                return ModelMetadata.ModelType;
-            }
-        }
 
         /// <summary>
         /// Gets or sets a model name which is explicitly set using an <see cref="IModelNameProvider"/>.
@@ -202,27 +183,12 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
         /// <summary>
         /// Gets or sets the <see cref="IValueProvider"/> associated with this context.
         /// </summary>
-        public IValueProvider ValueProvider { get; set; }
+        public IValueProvider ValueProvider { get; [param: NotNull] set; }
 
-        public Func<ModelBindingContext, string, bool> PropertyFilter
+        /// <summary>
-        {
+        /// Gets or sets a predicate which will be evaluated for each property to determine if the property
-            get
+        /// is eligible for model binding.
-            {
+        /// </summary>
-                if (_propertyFilter == null)
+        public Func<ModelBindingContext, string, bool> PropertyFilter { get; set; }
-                {
-                    _propertyFilter = _defaultPropertyFilter;
-                }
-                return _propertyFilter;
-            }
-            set { _propertyFilter = value; }
-        }
-
-        private void EnsureModelMetadata()
-        {
-            if (ModelMetadata == null)
-            {
-                throw new InvalidOperationException(Resources.ModelBindingContext_ModelMetadataMustBeSet);
-            }
-        }
     }
 }

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

@@ -73,12 +73,12 @@ namespace Microsoft.AspNet.Mvc
             [NotNull] OperationBindingContext operationContext)
         {
             var metadata = _modelMetadataProvider.GetMetadataForType(parameter.ParameterType);
-            var modelBindingContext = GetModelBindingContext(
+            var modelBindingContext = ModelBindingContext.CreateBindingContext(
-                parameter.Name,
+                operationContext,
+                modelState,
                 metadata,
                 parameter.BindingInfo,
-                modelState,
+                parameter.Name);
-                operationContext);
 
             var modelBindingResult = await operationContext.ModelBinder.BindModelAsync(modelBindingContext);
             if (modelBindingResult != null &&
@@ -187,26 +187,6 @@ namespace Microsoft.AspNet.Mvc
             }
         }
 
-        private static ModelBindingContext GetModelBindingContext(
-            string parameterName,
-            ModelMetadata metadata,
-            BindingInfo bindingInfo,
-            ModelStateDictionary modelState,
-            OperationBindingContext operationBindingContext)
-        {
-            var modelBindingContext = ModelBindingContext.GetModelBindingContext(
-                metadata,
-                bindingInfo,
-                parameterName);
-
-            modelBindingContext.IsTopLevelObject = true;
-            modelBindingContext.ModelState = modelState;
-            modelBindingContext.ValueProvider = operationBindingContext.ValueProvider;
-            modelBindingContext.OperationBindingContext = operationBindingContext;
-
-            return modelBindingContext;
-        }
-
         private OperationBindingContext GetOperationBindingContext(
             ActionContext actionContext,
             ActionBindingContext bindingContext)

src/Microsoft.AspNet.Mvc.Core/ModelBinding/CollectionModelBinder.cs

@@ -149,12 +149,16 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 bindingContext.ModelName,
                 bindingContext.ModelMetadata,
                 boundCollection);
+
+            var innerBindingContext = ModelBindingContext.CreateChildBindingContext(
+                bindingContext,
+                elementMetadata,
+                fieldName: bindingContext.FieldName,
+                modelName: bindingContext.ModelName,
+                model: null);
+
             foreach (var value in values)
             {
-                var innerBindingContext = ModelBindingContext.GetChildModelBindingContext(
-                    bindingContext,
-                    bindingContext.ModelName,
-                    elementMetadata);
                 innerBindingContext.ValueProvider = new CompositeValueProvider
                 {
                     // our temporary provider goes at the front of the list
@@ -222,10 +226,13 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
             foreach (var indexName in indexNames)
             {
                 var fullChildName = ModelNames.CreateIndexModelName(bindingContext.ModelName, indexName);
-                var childBindingContext = ModelBindingContext.GetChildModelBindingContext(
+                var childBindingContext = ModelBindingContext.CreateChildBindingContext(
                     bindingContext,
-                    fullChildName,
+                    elementMetadata,
-                    elementMetadata);
+                    fieldName: indexName,
+                    modelName: fullChildName,
+                    model: null);
+
 
                 var didBind = false;
                 object boundValue = null;

src/Microsoft.AspNet.Mvc.Core/ModelBinding/CompositeModelBinder.cs

@@ -148,6 +148,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 Model = oldBindingContext.Model,
                 ModelMetadata = oldBindingContext.ModelMetadata,
                 ModelName = modelName,
+                FieldName = oldBindingContext.FieldName,
                 ModelState = oldBindingContext.ModelState,
                 ValueProvider = oldBindingContext.ValueProvider,
                 OperationBindingContext = oldBindingContext.OperationBindingContext,

src/Microsoft.AspNet.Mvc.Core/ModelBinding/DictionaryModelBinder.cs

@@ -57,10 +57,12 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
             // Update the existing successful but empty ModelBindingResult.
             var metadataProvider = bindingContext.OperationBindingContext.MetadataProvider;
             var valueMetadata = metadataProvider.GetMetadataForType(typeof(TValue));
-            var valueBindingContext = ModelBindingContext.GetChildModelBindingContext(
+            var valueBindingContext = ModelBindingContext.CreateChildBindingContext(
                 bindingContext,
-                bindingContext.ModelName,
+                valueMetadata,
-                valueMetadata);
+                fieldName: bindingContext.FieldName,
+                modelName: bindingContext.ModelName,
+                model: null);
 
             var modelBinder = bindingContext.OperationBindingContext.ModelBinder;
             var validationNode = result.ValidationNode;

src/Microsoft.AspNet.Mvc.Core/ModelBinding/HeaderModelBinder.cs

@@ -32,7 +32,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
             var modelMetadata = bindingContext.ModelMetadata;
 
             // Property name can be null if the model metadata represents a type (rather than a property or parameter).
-            var headerName = bindingContext.BinderModelName ?? modelMetadata.PropertyName ?? bindingContext.ModelName;
+            var headerName = bindingContext.FieldName;
             object model = null;
             if (bindingContext.ModelType == typeof(string))
             {

src/Microsoft.AspNet.Mvc.Core/ModelBinding/KeyValuePairModelBinder.cs

@@ -93,11 +93,12 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 parentBindingContext.OperationBindingContext.MetadataProvider.GetMetadataForType(typeof(TModel));
             var propertyModelName =
                 ModelNames.CreatePropertyModelName(parentBindingContext.ModelName, propertyName);
-            var propertyBindingContext = ModelBindingContext.GetChildModelBindingContext(
+            var propertyBindingContext = ModelBindingContext.CreateChildBindingContext(
                 parentBindingContext,
+                propertyModelMetadata,
+                propertyName,
                 propertyModelName,
-                propertyModelMetadata);
+                model: null);
-            propertyBindingContext.BinderModelName = propertyModelMetadata.BinderModelName;
 
             var modelBindingResult = await propertyBindingContext.OperationBindingContext.ModelBinder.BindModelAsync(
                 propertyBindingContext);

src/Microsoft.AspNet.Mvc.Core/ModelBinding/MutableObjectModelBinder.cs

@@ -160,14 +160,17 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 {
                     isAnyPropertyEnabledForValueProviderBasedBinding = true;
 
-                    var propertyModelName = ModelNames.CreatePropertyModelName(
+                    var fieldName = propertyMetadata.BinderModelName ?? propertyMetadata.PropertyName;
+                    var modelName = ModelNames.CreatePropertyModelName(
                         context.ModelBindingContext.ModelName,
-                        propertyMetadata.BinderModelName ?? propertyMetadata.PropertyName);
+                        fieldName);
 
-                    var propertyModelBindingContext = ModelBindingContext.GetChildModelBindingContext(
+                    var propertyModelBindingContext = ModelBindingContext.CreateChildBindingContext(
                         context.ModelBindingContext,
-                        propertyModelName,
+                        propertyMetadata,
-                        propertyMetadata);
+                        fieldName: fieldName,
+                        modelName: modelName,
+                        model: null);
 
                     // If any property can return a true value.
                     if (CanBindValue(propertyModelBindingContext))
@@ -274,31 +277,34 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
             var results = new Dictionary<ModelMetadata, ModelBindingResult>();
             foreach (var propertyMetadata in propertyMetadatas)
             {
-                var propertyModelName = ModelNames.CreatePropertyModelName(
-                    bindingContext.ModelName,
-                    propertyMetadata.BinderModelName ?? propertyMetadata.PropertyName);
-                var childContext = ModelBindingContext.GetChildModelBindingContext(
-                    bindingContext,
-                    propertyModelName,
-                    propertyMetadata);
-
                 // ModelBindingContext.Model property values may be non-null when invoked via TryUpdateModel(). Pass
                 // complex (including collection) values down so that binding system does not unnecessarily recreate
                 // instances or overwrite inner properties that are not bound. No need for this with simple values
                 // because they will be overwritten if binding succeeds. Arrays are never reused because they cannot
                 // be resized.
+                object model = null;
                 if (propertyMetadata.PropertyGetter != null &&
                     propertyMetadata.IsComplexType &&
                     !propertyMetadata.ModelType.IsArray)
                 {
-                    childContext.Model = propertyMetadata.PropertyGetter(bindingContext.Model);
+                    model = propertyMetadata.PropertyGetter(bindingContext.Model);
                 }
 
-                var result = await bindingContext.OperationBindingContext.ModelBinder.BindModelAsync(childContext);
+                var fieldName = propertyMetadata.BinderModelName ?? propertyMetadata.PropertyName;
+                var modelName = ModelNames.CreatePropertyModelName(bindingContext.ModelName, fieldName);
+
+                var propertyContext = ModelBindingContext.CreateChildBindingContext(
+                    bindingContext,
+                    propertyMetadata,
+                    fieldName: fieldName,
+                    modelName: modelName,
+                    model: model);
+
+                var result = await bindingContext.OperationBindingContext.ModelBinder.BindModelAsync(propertyContext);
                 if (result == null)
                 {
                     // Could not bind. Let ProcessResult() know explicitly.
-                    result = new ModelBindingResult(model: null, key: propertyModelName, isModelSet: false);
+                    result = new ModelBindingResult(model: null, key: propertyContext.ModelName, isModelSet: false);
                 }
 
                 results[propertyMetadata] = result;
@@ -359,7 +365,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 var modelMetadataPredicate = context.ModelMetadata.PropertyBindingPredicateProvider?.PropertyFilter;
 
                 return
-                    context.PropertyFilter(context, propertyName) &&
+                    (context.PropertyFilter == null || context.PropertyFilter(context, propertyName)) &&
                     (modelMetadataPredicate == null || modelMetadataPredicate(context, propertyName));
             };
         }

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

@@ -293,21 +293,18 @@ namespace Microsoft.AspNet.Mvc
                 ModelBinder = modelBinder,
                 ValidatorProvider = validatorProvider,
                 MetadataProvider = metadataProvider,
-                HttpContext = httpContext
+                HttpContext = httpContext,
+                ValueProvider = valueProvider,
             };
 
-            var modelBindingContext = new ModelBindingContext
+            var modelBindingContext = ModelBindingContext.CreateBindingContext(
-            {
+                operationBindingContext,
-                Model = model,
+                modelState,
-                ModelMetadata = modelMetadata,
+                modelMetadata,
-                ModelName = prefix,
+                bindingInfo: null,
-                ModelState = modelState,
+                modelName: prefix ?? string.Empty);
-                ValueProvider = valueProvider,
+            modelBindingContext.Model = model;
-                FallbackToEmptyPrefix = true,
+            modelBindingContext.PropertyFilter = predicate;
-                IsTopLevelObject = true,
-                OperationBindingContext = operationBindingContext,
-                PropertyFilter = predicate,
-            };
 
             var modelBindingResult = await modelBinder.BindModelAsync(modelBindingContext);
             if (modelBindingResult != null && modelBindingResult.IsModelSet)

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/ArrayModelBinderTest.cs

@@ -222,11 +222,12 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 ModelMetadata = modelMetadata,
                 ModelName = "someName",
+                ModelState = new ModelStateDictionary(),
                 ValueProvider = valueProvider,
                 OperationBindingContext = new OperationBindingContext
                 {
                     ModelBinder = CreateIntBinder(),
-                    MetadataProvider = metadataProvider
+                    MetadataProvider = metadataProvider,
                 },
             };
             return bindingContext;

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/ByteArrayModelBinderTests.cs

@@ -129,10 +129,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 ModelMetadata = metadataProvider.GetMetadataForType(modelType),
                 ModelName = "foo",
+                ModelState = new ModelStateDictionary(),
                 ValueProvider = valueProvider,
                 OperationBindingContext  = new OperationBindingContext
                 {
-                    MetadataProvider = metadataProvider
+                    MetadataProvider = metadataProvider,
                 }
             };
             return bindingContext;

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/CollectionModelBinderTest.cs

@@ -419,6 +419,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 ModelMetadata = metadataProvider.GetMetadataForType(typeof(IList<int>)),
                 ModelName = "someName",
+                ModelState = new ModelStateDictionary(),
                 ValueProvider = valueProvider,
                 OperationBindingContext = new OperationBindingContext
                 {

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/CompositeModelBinderTest.cs

@@ -24,14 +24,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(int)),
                 ModelName = "someName",
                 ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider
                 {
                     { "someName", "dummyValue" }
                 },
-                OperationBindingContext = new OperationBindingContext
-                {
-                    ValidatorProvider = GetValidatorProvider()
-                }
             };
 
             var mockIntBinder = new Mock<IModelBinder>();
@@ -71,14 +68,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(List<int>)),
                 ModelName = "someName",
                 ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider
                 {
                     { "someOtherName", "dummyValue" }
                 },
-                OperationBindingContext = new OperationBindingContext
-                {
-                    ValidatorProvider = GetValidatorProvider()
-                }
             };
 
             var mockIntBinder = new Mock<IModelBinder>();
@@ -121,14 +115,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(List<int>)),
                 ModelName = "someName",
                 ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider
                 {
                     { "someOtherName", "dummyValue" }
                 },
-                OperationBindingContext = new OperationBindingContext
-                {
-                    ValidatorProvider = GetValidatorProvider()
-                }
             };
 
             var modelBinder = new Mock<IModelBinder>();
@@ -155,14 +146,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(List<int>)),
                 ModelName = "someName",
                 ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider
                 {
                     { "someOtherName", "dummyValue" }
                 },
-                OperationBindingContext = new OperationBindingContext
-                {
-                    ValidatorProvider = GetValidatorProvider()
-                }
             };
 
             var count = 0;
@@ -201,14 +189,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(List<int>)),
                 ModelName = "someName",
                 ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider
                 {
                     { "someOtherName", "dummyValue" }
                 },
-                OperationBindingContext = new OperationBindingContext
-                {
-                    ValidatorProvider = GetValidatorProvider()
-                }
             };
 
             var modelBinder = new Mock<IModelBinder>();
@@ -238,14 +223,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(List<int>)),
                 ModelName = "someName",
                 ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider
                 {
                     { "someOtherName", "dummyValue" }
                 },
-                OperationBindingContext = new OperationBindingContext
-                {
-                    ValidatorProvider = GetValidatorProvider()
-                }
             };
 
             var modelBinder = new Mock<IModelBinder>();
@@ -276,14 +258,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(List<int>)),
                 ModelName = "someName",
                 ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider
                 {
                     { "someOtherName", "dummyValue" }
                 },
-                OperationBindingContext = new OperationBindingContext
-                {
-                    ValidatorProvider = GetValidatorProvider()
-                }
             };
 
             var modelBinder = new Mock<IModelBinder>();
@@ -318,6 +297,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 FallbackToEmptyPrefix = false,
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(List<int>)),
+                ModelState = new ModelStateDictionary(),
             };
 
             // Act
@@ -341,7 +321,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
                 FallbackToEmptyPrefix = true,
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(typeof(int)),
                 ModelState = new ModelStateDictionary(),
-                OperationBindingContext = Mock.Of<OperationBindingContext>(),
+                OperationBindingContext = new OperationBindingContext(),
             };
 
             // Act
@@ -504,24 +484,23 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             Assert.Same(validationNode, result.ValidationNode);
         }
 
-        private static ModelBindingContext CreateBindingContext(IModelBinder binder,
+        private static ModelBindingContext CreateBindingContext(
-                                                                IValueProvider valueProvider,
+            IModelBinder binder,
-                                                                Type type,
+            IValueProvider valueProvider,
-                                                                IModelValidatorProvider validatorProvider = null)
+            Type type)
         {
-            validatorProvider = validatorProvider ?? GetValidatorProvider();
             var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();
             var bindingContext = new ModelBindingContext
             {
                 FallbackToEmptyPrefix = true,
                 ModelMetadata = metadataProvider.GetMetadataForType(type),
+                ModelName = "parameter",
                 ModelState = new ModelStateDictionary(),
                 ValueProvider = valueProvider,
                 OperationBindingContext = new OperationBindingContext
                 {
                     MetadataProvider = metadataProvider,
                     ModelBinder = binder,
-                    ValidatorProvider = validatorProvider
                 }
             };
             return bindingContext;
@@ -547,26 +526,6 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             return shimBinder;
         }
 
-        private static IModelValidatorProvider GetValidatorProvider(params IModelValidator[] validators)
-        {
-            var provider = new Mock<IModelValidatorProvider>();
-            provider
-                .Setup(v => v.GetValidators(It.IsAny<ModelValidatorProviderContext>()))
-                .Callback<ModelValidatorProviderContext>(c =>
-                {
-                    if (validators == null)
-                    {
-                        return;
-                    }
-
-                    foreach (var validator in validators)
-                    {
-                        c.Validators.Add(validator);
-                    }
-                });
-
-            return provider.Object;
-        }
 
         private class SimplePropertiesModel
         {

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/DictionaryModelBinderTest.cs

@@ -429,6 +429,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
         {
             var modelBindingContext = new ModelBindingContext()
             {
+                ModelState = new ModelStateDictionary(),
                 OperationBindingContext = new OperationBindingContext()
                 {
                     HttpContext = new DefaultHttpContext(),
@@ -510,6 +511,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 ModelMetadata = metadataProvider.GetMetadataForType(typeof(IDictionary<int, string>)),
                 ModelName = "someName",
+                ModelState = new ModelStateDictionary(),
                 OperationBindingContext = new OperationBindingContext
                 {
                     ModelBinder = binder.Object,

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/FormFileModelBinderTest.cs

@@ -159,6 +159,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
             {
                 ModelMetadata = metadataProvider.GetMetadataForType(modelType),
                 ModelName = "file",
+                ModelState = new ModelStateDictionary(),
                 OperationBindingContext = new OperationBindingContext
                 {
                     ModelBinder = new FormFileModelBinder(),

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/HeaderModelBinderTests.cs

@@ -40,7 +40,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             var binder = new HeaderModelBinder();
             var modelBindingContext = GetBindingContext(type);
 
-            modelBindingContext.ModelName = header;
+            modelBindingContext.FieldName = header;
             modelBindingContext.OperationBindingContext.HttpContext.Request.Headers.Add(header, new[] { headerValue });
 
             // Act
@@ -61,7 +61,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             var binder = new HeaderModelBinder();
             var modelBindingContext = GetBindingContext(type);
 
-            modelBindingContext.ModelName = header;
+            modelBindingContext.FieldName = header;
             modelBindingContext.OperationBindingContext.HttpContext.Request.Headers.Add(header, new[] { headerValue });
 
             // Act
@@ -81,6 +81,8 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 ModelMetadata = modelMetadata,
                 ModelName = "modelName",
+                FieldName = "modelName",
+                ModelState = new ModelStateDictionary(),
                 OperationBindingContext = new OperationBindingContext
                 {
                     ModelBinder = new HeaderModelBinder(),

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/KeyValuePairModelBinderTest.cs

@@ -255,6 +255,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 ModelMetadata = metataProvider.GetMetadataForType(keyValuePairType ?? typeof(KeyValuePair<int, string>)),
                 ModelName = "someName",
+                ModelState = new ModelStateDictionary(),
                 ValueProvider = valueProvider,
                 OperationBindingContext = new OperationBindingContext
                 {

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/ModelBindingContextTest.cs

@@ -10,14 +10,15 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
     public class ModelBindingContextTest
     {
         [Fact]
-        public void GetChildModelBindingContext()
+        public void CreateChildBindingContext_CopiesProperties()
         {
             // Arrange
             var originalBindingContext = new ModelBindingContext
             {
+                Model = new object(),
                 ModelMetadata = new TestModelMetadataProvider().GetMetadataForType(typeof(object)),
                 ModelName = "theName",
-                ModelState = new ModelStateDictionary(),
+                OperationBindingContext = new OperationBindingContext(),
                 ValueProvider = new SimpleValueProvider()
             };
 
@@ -32,19 +33,27 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             var newModelMetadata = metadataProvider.GetMetadataForType(typeof(object));
             
             // Act
-            var newBindingContext = ModelBindingContext.GetChildModelBindingContext(
+            var newBindingContext = ModelBindingContext.CreateChildBindingContext(
                 originalBindingContext,
-                string.Empty,
+                newModelMetadata,
-                newModelMetadata);
+                fieldName: "fieldName",
+                modelName: "modelprefix.fieldName",
+                model: null);
 
             // Assert
-            Assert.Same(newModelMetadata, newBindingContext.ModelMetadata);
-            Assert.Same(newModelMetadata.BindingSource, newBindingContext.BindingSource);
             Assert.Same(newModelMetadata.BinderModelName, newBindingContext.BinderModelName);
             Assert.Same(newModelMetadata.BinderType, newBindingContext.BinderType);
-            Assert.Equal("", newBindingContext.ModelName);
+            Assert.Same(newModelMetadata.BindingSource, newBindingContext.BindingSource);
-            Assert.Equal(originalBindingContext.ModelState, newBindingContext.ModelState);
+            Assert.False(newBindingContext.FallbackToEmptyPrefix);
-            Assert.Equal(originalBindingContext.ValueProvider, newBindingContext.ValueProvider);
+            Assert.Equal("fieldName", newBindingContext.FieldName);
+            Assert.False(newBindingContext.IsFirstChanceBinding);
+            Assert.False(newBindingContext.IsTopLevelObject);
+            Assert.Null(newBindingContext.Model);
+            Assert.Same(newModelMetadata, newBindingContext.ModelMetadata);
+            Assert.Equal("modelprefix.fieldName", newBindingContext.ModelName);
+            Assert.Same(originalBindingContext.ModelState, newBindingContext.ModelState);
+            Assert.Same(originalBindingContext.OperationBindingContext, newBindingContext.OperationBindingContext);
+            Assert.Same(originalBindingContext.ValueProvider, newBindingContext.ValueProvider);
         }
 
         [Fact]

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/MutableObjectModelBinderTest.cs

@@ -796,6 +796,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 Model = model,
                 ModelMetadata = containerMetadata,
                 ModelName = "theModel",
+                ModelState = new ModelStateDictionary(),
                 OperationBindingContext = new OperationBindingContext
                 {
                     MetadataProvider = TestModelMetadataProvider.CreateDefaultProvider(),
@@ -846,6 +847,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
                 Model = model,
                 ModelMetadata = containerMetadata,
                 ModelName = "theModel",
+                ModelState = new ModelStateDictionary(),
                 OperationBindingContext = new OperationBindingContext
                 {
                     MetadataProvider = TestModelMetadataProvider.CreateDefaultProvider(),
@@ -1649,9 +1651,9 @@ namespace Microsoft.AspNet.Mvc.ModelBinding
             return new ModelBindingContext
             {
                 Model = model,
-                ModelState = new ModelStateDictionary(),
                 ModelMetadata = metadata,
                 ModelName = "theModel",
+                ModelState = new ModelStateDictionary(),
                 OperationBindingContext = new OperationBindingContext
                 {
                     MetadataProvider = TestModelMetadataProvider.CreateDefaultProvider(),

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/SimpleTypeModelBinderTest.cs

@@ -185,6 +185,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Test
             {
                 ModelMetadata = new EmptyModelMetadataProvider().GetMetadataForType(modelType),
                 ModelName = "theModelName",
+                ModelState = new ModelStateDictionary(),
                 ValueProvider = new SimpleValueProvider() // empty
             };
         }