Added ViewComponentTagHelperDescriptorResolver and related stuff

src/Microsoft.AspNetCore.Mvc.Razor.Host/Internal/GeneratedViewComponentTagHelperContext.cs

@@ -17,6 +17,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Host.Internal
             InvokeAsyncMethodName = "InvokeAsync";
             IViewComponentHelperTypeName = "Microsoft.AspNetCore.Mvc.IViewComponentHelper";
             IViewContextAwareTypeName = "Microsoft.AspNetCore.Mvc.ViewFeatures.IViewContextAware";
+            ViewContextAttributeTypeName = "Microsoft.AspNetCore.Mvc.ViewFeatures.ViewContextAttribute";
             ViewContextTypeName = "Microsoft.AspNetCore.Mvc.Rendering.ViewContext";
         }
 
@@ -44,5 +45,10 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Host.Internal
         /// Name of the ViewContext type for view execution.
         /// </summary>
         public string ViewContextTypeName { get; set; }
+
+        /// <summary>
+        /// Name of the ViewContextAttribute type for view execution.
+        /// </summary>
+        public string ViewContextAttributeTypeName { get; set; }
     }
 }

src/Microsoft.AspNetCore.Mvc.Razor.Host/Internal/ViewComponentTagHelperChunkVisitor.cs

@@ -119,7 +119,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Host.Internal
             Writer.Write("[")
               .Write(typeof(HtmlAttributeNotBoundAttribute).FullName)
               .WriteParameterSeparator()
-              .Write($"global::{_context.ViewContextTypeName}")
+              .Write($"global::{_context.ViewContextAttributeTypeName}")
               .WriteLine("]");
 
             Writer.WriteAutoPropertyDeclaration(

src/Microsoft.AspNetCore.Mvc.Razor/DependencyInjection/MvcRazorMvcCoreBuilderExtensions.cs

@@ -165,7 +165,11 @@ namespace Microsoft.Extensions.DependencyInjection
 
             services.TryAddSingleton<ITagHelperTypeResolver, TagHelperTypeResolver>();
             services.TryAddSingleton<ITagHelperDescriptorFactory>(s => new TagHelperDescriptorFactory(designTime: false));
-            services.TryAddSingleton<ITagHelperDescriptorResolver, TagHelperDescriptorResolver>();
+            services.TryAddSingleton<TagHelperDescriptorResolver, TagHelperDescriptorResolver>();
+
+            // And ViewComponentTagHelper resolver.
+            services.TryAddSingleton<ViewComponentTagHelperDescriptorResolver, ViewComponentTagHelperDescriptorResolver>();
+            services.TryAddSingleton<ITagHelperDescriptorResolver, CompositeTagHelperDescriptorResolver>();
 
             // Caches compilation artifacts across the lifetime of the application.
             services.TryAddSingleton<ICompilerCacheProvider, DefaultCompilerCacheProvider>();

src/Microsoft.AspNetCore.Mvc.Razor/Internal/CompositeTagHelperDescriptorResolver.cs

@@ -0,0 +1,36 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using Microsoft.AspNetCore.Razor.Compilation.TagHelpers;
+using Microsoft.AspNetCore.Razor.Runtime.TagHelpers;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public class CompositeTagHelperDescriptorResolver : ITagHelperDescriptorResolver
+    {
+        public IList<TagHelperDescriptorResolver> _resolvers;
+
+        public CompositeTagHelperDescriptorResolver(
+            TagHelperDescriptorResolver tagHelperDescriptorResolver,
+            ViewComponentTagHelperDescriptorResolver viewComponentTagHelperDescriptorResolver)
+        {
+            _resolvers = new List<TagHelperDescriptorResolver>();
+            _resolvers.Add(tagHelperDescriptorResolver);
+            _resolvers.Add(viewComponentTagHelperDescriptorResolver);
+        }
+
+        public IEnumerable<TagHelperDescriptor> Resolve(TagHelperDescriptorResolutionContext resolutionContext)
+        {
+            var descriptors = new List<TagHelperDescriptor>();
+
+            foreach (var resolver in _resolvers)
+            {
+                var currentDescriptors = resolver.Resolve(resolutionContext);
+                descriptors.AddRange(currentDescriptors);
+            }
+
+            return descriptors;
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/ViewComponentTagHelperDescriptorResolver.cs

@@ -0,0 +1,31 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using Microsoft.AspNetCore.Mvc.ViewComponents;
+using Microsoft.AspNetCore.Razor;
+using Microsoft.AspNetCore.Razor.Compilation.TagHelpers;
+using Microsoft.AspNetCore.Razor.Runtime.TagHelpers;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public class ViewComponentTagHelperDescriptorResolver : TagHelperDescriptorResolver
+    {
+        ViewComponentTagHelperDescriptorFactory _descriptorFactory;
+
+        public ViewComponentTagHelperDescriptorResolver(
+            IViewComponentDescriptorProvider viewComponentDescriptorProvider)
+            : base(designTime: true)
+        {
+            _descriptorFactory = new ViewComponentTagHelperDescriptorFactory(viewComponentDescriptorProvider);
+        }
+
+        protected override IEnumerable<TagHelperDescriptor> ResolveDescriptorsInAssembly(
+            string assemblyName,
+            SourceLocation documentLocation,
+            ErrorSink errorSink)
+        {
+            return _descriptorFactory.CreateDescriptors(assemblyName);
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.Razor.Host.Test/Internal/ViewComponentTagHelperChunkVisitorTest.cs

@@ -1,7 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
 using System.Collections.Generic;
 using System.Reflection;
 using Microsoft.AspNetCore.Mvc.Razor.Host.Internal;

test/Microsoft.AspNetCore.Mvc.Razor.Host.Test/TestFiles/Output/Runtime/GeneratedViewComponentTagHelperClasses.cs

@@ -6,7 +6,7 @@ public class __Generated__FooViewComponentTagHelper : Microsoft.AspNetCore.Razor
     {
         _viewComponentHelper = viewComponentHelper;
     }
-    [Microsoft.AspNetCore.Razor.TagHelpers.HtmlAttributeNotBoundAttribute, global::Microsoft.AspNetCore.Mvc.Rendering.ViewContext]
+    [Microsoft.AspNetCore.Razor.TagHelpers.HtmlAttributeNotBoundAttribute, global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewContextAttribute]
     public global::Microsoft.AspNetCore.Mvc.Rendering.ViewContext ViewContext { get; set; }
     public System.String Attribute { get; set; }
     public override async global::System.Threading.Tasks.Task ProcessAsync(Microsoft.AspNetCore.Razor.TagHelpers.TagHelperContext context, Microsoft.AspNetCore.Razor.TagHelpers.TagHelperOutput output)
@@ -25,7 +25,7 @@ public class __Generated__BarViewComponentTagHelper : Microsoft.AspNetCore.Razor
     {
         _viewComponentHelper = viewComponentHelper;
     }
-    [Microsoft.AspNetCore.Razor.TagHelpers.HtmlAttributeNotBoundAttribute, global::Microsoft.AspNetCore.Mvc.Rendering.ViewContext]
+    [Microsoft.AspNetCore.Razor.TagHelpers.HtmlAttributeNotBoundAttribute, global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewContextAttribute]
     public global::Microsoft.AspNetCore.Mvc.Rendering.ViewContext ViewContext { get; set; }
     public System.String Attribute { get; set; }
     public override async global::System.Threading.Tasks.Task ProcessAsync(Microsoft.AspNetCore.Razor.TagHelpers.TagHelperContext context, Microsoft.AspNetCore.Razor.TagHelpers.TagHelperOutput output)