Address #2526; remove use of a required validator when validating `[B…

…indRequired]`

- only use MVC error message when `[BindRequired]` is violated
- update that error message to more clearly describe the problem
- enable all tests skipped due to dupe bug #2493
- update expectations of a few tests using the old messages

nits:
- rename `ModelBinding_MissingRequiredMember` to `ModelBinding_MissingBindRequiredMember`
- remove `<param>` description of removed `requiredValidator` parameter
- remove unused `MutableObjectModelBinderTest.GetRequiredValidator()`

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

@@ -3,7 +3,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.ComponentModel;
 using System.Linq;
 using System.Reflection;
 using System.Threading.Tasks;
@@ -364,42 +363,19 @@ internal ModelValidationNode ProcessDto(
             var modelExplorer = metadataProvider.GetModelExplorerForType(bindingContext.ModelType, bindingContext.Model);
             var validationInfo = GetPropertyValidationInfo(bindingContext);
 
-            // Eliminate provided properties from requiredProperties; leaving just *missing* required properties.
+            // Eliminate provided properties from RequiredProperties; leaving just *missing* required properties.
             var boundProperties = dto.Results.Where(p => p.Value.IsModelSet).Select(p => p.Key.PropertyName);
             validationInfo.RequiredProperties.ExceptWith(boundProperties);
 
             foreach (var missingRequiredProperty in validationInfo.RequiredProperties)
             {
-                var addedError = false;
-
-                // We want to provide the 'null' value, not the value of model.Property,
-                // so avoiding modelExplorer.GetProperty here which would call the actual getter on the
-                // model. This avoids issues with value types, or properties with pre-initialized values.
-                var propertyExplorer = modelExplorer.GetExplorerForProperty(missingRequiredProperty, model: null);
-
+                var propertyExplorer = modelExplorer.GetExplorerForProperty(missingRequiredProperty);
                 var propertyName = propertyExplorer.Metadata.BinderModelName ?? missingRequiredProperty;
-                var modelStateKey = ModelNames.CreatePropertyModelName(
-                    bindingContext.ModelName,
-                    propertyName);
-
-                // Get the first 'required' validator (if any) to get custom error message.
-                var validatorProviderContext = new ModelValidatorProviderContext(propertyExplorer.Metadata);
-                bindingContext.OperationBindingContext.ValidatorProvider.GetValidators(validatorProviderContext);
-                var validator = validatorProviderContext.Validators.FirstOrDefault(v => v.IsRequired);
+                var modelStateKey = ModelNames.CreatePropertyModelName(bindingContext.ModelName, propertyName);
 
-                if (validator != null)
-                {
-                    addedError = RunValidator(validator, bindingContext, propertyExplorer, modelStateKey);
-                }
-
-                // Fall back to default message if BindingBehaviorAttribute required this property and we have no
-                // actual validator for it.
-                if (!addedError)
-                {
-                    bindingContext.ModelState.TryAddModelError(
-                        modelStateKey,
-                        Resources.FormatModelBinding_MissingRequiredMember(propertyName));
-                }
+                bindingContext.ModelState.TryAddModelError(
+                    modelStateKey,
+                    Resources.FormatModelBinding_MissingBindRequiredMember(propertyName));
             }
 
             // For each property that ComplexModelDtoModelBinder attempted to bind, call the setter, recording
@@ -436,10 +412,6 @@ internal ModelValidationNode ProcessDto(
         /// </param>
         /// <param name="propertyMetadata">The <see cref="ModelMetadata"/> for the property to set.</param>
         /// <param name="dtoResult">The <see cref="ModelBindingResult"/> for the property's new value.</param>
-        /// <param name="requiredValidator">
-        /// The <see cref="IModelValidator"/> which ensures the value is not <c>null</c>. Or <c>null</c> if no such
-        /// requirement exists.
-        /// </param>
         /// <remarks>Should succeed in all cases that <see cref="CanUpdateProperty"/> returns <c>true</c>.</remarks>
         protected virtual void SetProperty(
             [NotNull] ModelBindingContext bindingContext,

src/Microsoft.AspNet.Mvc.Core/Resources.resx

@@ -1,17 +1,17 @@
 <?xml version="1.0" encoding="utf-8"?>
 <root>
-  <!-- 
-    Microsoft ResX Schema 
-    
+  <!--
+    Microsoft ResX Schema
+
     Version 2.0
-    
-    The primary goals of this format is to allow a simple XML format 
-    that is mostly human readable. The generation and parsing of the 
-    various data types are done through the TypeConverter classes 
+
+    The primary goals of this format is to allow a simple XML format
+    that is mostly human readable. The generation and parsing of the
+    various data types are done through the TypeConverter classes
     associated with the data types.
-    
+
     Example:
-    
+
     ... ado.net/XML headers & schema ...
     <resheader name="resmimetype">text/microsoft-resx</resheader>
     <resheader name="version">2.0</resheader>
@@ -26,36 +26,36 @@
         <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
         <comment>This is a comment</comment>
     </data>
-                
-    There are any number of "resheader" rows that contain simple 
+
+    There are any number of "resheader" rows that contain simple
     name/value pairs.
-    
-    Each data row contains a name, and value. The row also contains a 
-    type or mimetype. Type corresponds to a .NET class that support 
-    text/value conversion through the TypeConverter architecture. 
-    Classes that don't support this are serialized and stored with the 
+
+    Each data row contains a name, and value. The row also contains a
+    type or mimetype. Type corresponds to a .NET class that support
+    text/value conversion through the TypeConverter architecture.
+    Classes that don't support this are serialized and stored with the
     mimetype set.
-    
-    The mimetype is used for serialized objects, and tells the 
-    ResXResourceReader how to depersist the object. This is currently not 
+
+    The mimetype is used for serialized objects, and tells the
+    ResXResourceReader how to depersist the object. This is currently not
     extensible. For a given mimetype the value must be set accordingly:
-    
-    Note - application/x-microsoft.net.object.binary.base64 is the format 
-    that the ResXResourceWriter will generate, however the reader can 
+
+    Note - application/x-microsoft.net.object.binary.base64 is the format
+    that the ResXResourceWriter will generate, however the reader can
     read any of the formats listed below.
-    
+
     mimetype: application/x-microsoft.net.object.binary.base64
-    value   : The object must be serialized with 
+    value   : The object must be serialized with
             : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
             : and then encoded with base64 encoding.
-    
+
     mimetype: application/x-microsoft.net.object.soap.base64
-    value   : The object must be serialized with 
+    value   : The object must be serialized with
             : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
             : and then encoded with base64 encoding.
 
     mimetype: application/x-microsoft.net.object.bytearray.base64
-    value   : The object must be serialized into a byte array 
+    value   : The object must be serialized into a byte array
             : using a System.ComponentModel.TypeConverter
             : and then encoded with base64 encoding.
     -->
@@ -499,8 +499,8 @@
   <data name="ModelBinderUtil_ValueInvalidGeneric" xml:space="preserve">
     <value>The supplied value is invalid for {0}.</value>
   </data>
-  <data name="ModelBinding_MissingRequiredMember" xml:space="preserve">
-    <value>The '{0}' property is required.</value>
+  <data name="ModelBinding_MissingBindRequiredMember" xml:space="preserve">
+    <value>A value for the '{0}' property was not provided.</value>
   </data>
   <data name="ModelBinding_ValueRequired" xml:space="preserve">
     <value>A value is required.</value>

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

@@ -793,7 +793,7 @@ public void ProcessDto_BindRequiredFieldMissing_RaisesModelError()
             var modelError = Assert.Single(modelState.Errors);
             Assert.Null(modelError.Exception);
             Assert.NotNull(modelError.ErrorMessage);
-            Assert.Equal("The 'Age' property is required.", modelError.ErrorMessage);
+            Assert.Equal("A value for the 'Age' property was not provided.", modelError.ErrorMessage);
         }
 
         [Fact]
@@ -844,7 +844,7 @@ public void ProcessDto_DataMemberIsRequiredFieldMissing_RaisesModelError()
             var modelError = Assert.Single(modelState.Errors);
             Assert.Null(modelError.Exception);
             Assert.NotNull(modelError.ErrorMessage);
-            Assert.Equal("The 'Age' property is required.", modelError.ErrorMessage);
+            Assert.Equal("A value for the 'Age' property was not provided.", modelError.ErrorMessage);
         }
 
         [Fact]
@@ -1147,9 +1147,9 @@ public void ProcessDto_ProvideRequiredFields_Success()
             Assert.Equal(0m, model.PropertyWithDefaultValue);     // [DefaultValue] has no effect
         }
 
-        // This uses [Required] with [BindRequired] to provide a custom validation messsage.
+        // [Required] cannot provide a custom validation for [BindRequired] errors.
         [Fact]
-        public void ProcessDto_ValueTypePropertyWithBindRequired_CustomValidationMessage()
+        public void ProcessDto_ValueTypePropertyWithBindRequired_RequiredValidatorIgnored()
         {
             // Arrange
             var model = new ModelWithBindRequiredAndRequiredAttribute();
@@ -1191,16 +1191,16 @@ public void ProcessDto_ValueTypePropertyWithBindRequired_CustomValidationMessage
                 .Value;
             var error = Assert.Single(entry.Errors);
             Assert.Null(error.Exception);
-            Assert.Equal("Custom Message ValueTypeProperty", error.ErrorMessage);
+            Assert.Equal("A value for the 'ValueTypeProperty' property was not provided.", error.ErrorMessage);
 
             // Model gets provided values.
             Assert.Equal(0, model.ValueTypeProperty);
             Assert.Equal("value", model.ReferenceTypeProperty);
         }
 
-        // This uses [Required] with [BindRequired] to provide a custom validation messsage.
+        // [Required] cannot provide a custom validation for [BindRequired] errors.
         [Fact]
-        public void ProcessDto_ReferenceTypePropertyWithBindRequired_CustomValidationMessage()
+        public void ProcessDto_ReferenceTypePropertyWithBindRequired_RequiredValidatorIgnored()
         {
             // Arrange
             var model = new ModelWithBindRequiredAndRequiredAttribute();
@@ -1242,7 +1242,7 @@ public void ProcessDto_ReferenceTypePropertyWithBindRequired_CustomValidationMes
                 .Value;
             var error = Assert.Single(entry.Errors);
             Assert.Null(error.Exception);
-            Assert.Equal("Custom Message ReferenceTypeProperty", error.ErrorMessage);
+            Assert.Equal("A value for the 'ReferenceTypeProperty' property was not provided.", error.ErrorMessage);
 
             // Model gets provided values.
             Assert.Equal(17, model.ValueTypeProperty);
@@ -1715,15 +1715,6 @@ private static ModelBindingContext CreateContext(ModelMetadata metadata, object
             };
         }
 
-        private static IModelValidator GetRequiredValidator(ModelBindingContext bindingContext, ModelMetadata propertyMetadata)
-        {
-            var validatorProvider = bindingContext.OperationBindingContext.ValidatorProvider;
-            var validatorProviderContext = new ModelValidatorProviderContext(propertyMetadata);
-            validatorProvider.GetValidators(validatorProviderContext);
-
-            return validatorProviderContext.Validators.FirstOrDefault(v => v.IsRequired);
-        }
-
         private static ModelMetadata GetMetadataForCanUpdateProperty(string propertyName)
         {
             var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

test/Microsoft.AspNet.Mvc.FunctionalTests/ModelBindingBindingBehaviorTest.cs

@@ -49,10 +49,14 @@ public async Task BindingBehavior_MissingRequiredProperties_ValidationErrors()
             Assert.Equal(2, errors.Count);
 
             var error = Assert.Single(errors, kvp => kvp.Key == "model.BehaviourRequiredProperty");
-            Assert.Equal("The 'BehaviourRequiredProperty' property is required.", ((JArray)error.Value)[0].Value<string>());
+            Assert.Equal(
+                "A value for the 'BehaviourRequiredProperty' property was not provided.",
+                ((JArray)error.Value)[0].Value<string>());
 
             error = Assert.Single(errors, kvp => kvp.Key == "model.BindRequiredProperty");
-            Assert.Equal("The 'BindRequiredProperty' property is required.", ((JArray)error.Value)[0].Value<string>());
+            Assert.Equal(
+                "A value for the 'BindRequiredProperty' property was not provided.",
+                ((JArray)error.Value)[0].Value<string>());
         }
 
         [Fact]

test/Microsoft.AspNet.Mvc.FunctionalTests/ModelBindingDataMemberRequiredTest.cs

@@ -49,7 +49,9 @@ public async Task DataMember_MissingRequiredProperty_ValidationError()
             Assert.Equal(1, errors.Count);
 
             var error = Assert.Single(errors, kvp => kvp.Key == "model.RequiredProperty");
-            Assert.Equal("The 'RequiredProperty' property is required.", ((JArray)error.Value)[0].Value<string>());
+            Assert.Equal(
+                "A value for the 'RequiredProperty' property was not provided.",
+                ((JArray)error.Value)[0].Value<string>());
         }
 
         [Fact]