Issue #1214: Cannot pass a int parameter to the views from ViewComponent.

Fix: Checking if the model is not null in the Copy constructor of ViewDataDictionary.

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

@@ -51,7 +51,12 @@ namespace Microsoft.AspNet.Mvc
                    new TemplateInfo(source.TemplateInfo))
         {
             _modelMetadata = source.ModelMetadata;
-            SetModel(model);
+            // If we're constructing a derived ViewDataDictionary (or any other value type),
+            // SetModel will throw if we try to set it to null. We should not throw in that case.
+            if (model != null)
+            {
+                SetModel(model);
+            }
         }
 
         private ViewDataDictionary(IModelMetadataProvider metadataProvider,

test/Microsoft.AspNet.Mvc.Core.Test/ViewDataDictionaryTest.cs

@@ -116,6 +116,46 @@ namespace Microsoft.AspNet.Mvc.Core
             Assert.IsType<CopyOnWriteDictionary<string, object>>(viewData.Data);
         }
 
+        [Fact]
+        public void CopyConstructorDoesNotThrowOnNullModel()
+        {
+            // Arrange
+            var metadataProvider = new EmptyModelMetadataProvider();
+            var source = new ViewDataDictionary(metadataProvider);
+            source["key1"] = "value1";
+
+            // Act
+            var viewData = new ViewDataDictionary(source, null);
+
+            // Assert
+            Assert.NotNull(viewData.ModelState);
+            Assert.NotNull(viewData.TemplateInfo);
+            Assert.Null(viewData.Model);
+            Assert.Null(viewData.ModelMetadata);
+            Assert.Equal("value1", viewData["key1"]);
+            Assert.IsType<CopyOnWriteDictionary<string, object>>(viewData.Data);
+        }
+
+        [Fact]
+        public void CopyConstructorDoesNotThrowOnNullModel_WithValueTypeTModel()
+        {
+            // Arrange
+            var metadataProvider = new EmptyModelMetadataProvider();
+            var source = new ViewDataDictionary(metadataProvider);
+            source["key1"] = "value1";
+
+            // Act
+            var viewData = new ViewDataDictionary<int>(source, null);
+
+            // Assert
+            Assert.NotNull(viewData.ModelState);
+            Assert.NotNull(viewData.TemplateInfo);
+            Assert.Throws<NullReferenceException>(() => viewData.Model);
+            Assert.NotNull(viewData.ModelMetadata);
+            Assert.Equal("value1", viewData["key1"]);
+            Assert.IsType<CopyOnWriteDictionary<string, object>>(viewData.Data);
+        }
+
         private class TestModel
         {
         }

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

@@ -51,5 +51,18 @@ namespace Microsoft.AspNet.Mvc.FunctionalTests
             // Assert
             Assert.Equal(expected, body.Trim());
         }
+
+        [Fact]
+        public async Task ViewComponents_SupportsValueType()
+        {
+            var server = TestServer.Create(_provider, _app);
+            var client = server.CreateClient();
+
+            // Act
+            var body = await client.GetStringAsync("http://localhost/Home/ViewWithIntegerViewComponent");
+
+            // Assert
+            Assert.Equal("10", body.Trim());
+        }
     }
 }

test/WebSites/ViewComponentWebSite/HomeController.cs

@@ -16,5 +16,10 @@ namespace ViewComponentWebSite
         {
             return new ViewResult();
         }
+
+        public ViewResult ViewWithIntegerViewComponent()
+        {
+            return new ViewResult();
+        }
     }
 }

test/WebSites/ViewComponentWebSite/IntegerViewComponent.cs

@@ -0,0 +1,15 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNet.Mvc;
+
+namespace ViewComponentWebSite
+{
+    public class IntegerViewComponent : ViewComponent
+    {
+        public IViewComponentResult Invoke(int valueFromView)
+        {
+            return View(valueFromView);
+        }
+    }
+}

test/WebSites/ViewComponentWebSite/Views/Shared/Components/Integer/Default.cshtml

@@ -0,0 +1,2 @@
+@model int
+@Model

test/WebSites/ViewComponentWebSite/Views/Shared/ViewWithIntegerViewComponent.cshtml

@@ -0,0 +1 @@
+@Component.Invoke("Integer", 10)