Merge branch 'rel/vs15.7' into dev

src/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/RazorExtensions.cs

@@ -4,6 +4,7 @@
 using System;
 using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.AspNetCore.Razor.Language.Extensions;
+using Microsoft.CodeAnalysis.Razor;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
 {
@@ -22,6 +23,8 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
             FunctionsDirective.Register(builder);
             InheritsDirective.Register(builder);
 
+            builder.Features.Add(new DefaultTagHelperDescriptorProvider());
+
             // Register section directive with the 1.x compatible target extension.
             builder.AddDirective(SectionDirective.Directive);
             builder.Features.Add(new SectionDirectivePass());
@@ -67,6 +70,8 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
             FunctionsDirective.Register(builder);
             InheritsDirective.Register(builder);
 
+            builder.Features.Add(new DefaultTagHelperDescriptorProvider());
+
             // Register section directive with the 1.x compatible target extension.
             builder.AddDirective(SectionDirective.Directive);
             builder.Features.Add(new SectionDirectivePass());

src/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/ViewComponentTagHelperDescriptorProvider.cs

@@ -11,10 +11,6 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
 {
     public sealed class ViewComponentTagHelperDescriptorProvider : RazorEngineFeatureBase, ITagHelperDescriptorProvider
     {
-        // Hack for testability. The visitor will normally just no op if we're not referencing
-        // an appropriate version of MVC.
-        internal bool ForceEnabled { get; set; }
-
         public int Order { get; set; }
 
         public void Execute(TagHelperDescriptorProviderContext context)
@@ -33,10 +29,6 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
 
             var types = new List<INamedTypeSymbol>();
             var visitor = ViewComponentTypeVisitor.Create(compilation, types);
-            if (ForceEnabled)
-            {
-                visitor.Enabled = true;
-            }
 
             // We always visit the global namespace.
             visitor.Visit(compilation.Assembly.GlobalNamespace);

src/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/ViewComponentTypeVisitor.cs

@@ -18,22 +18,8 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
 
         public static ViewComponentTypeVisitor Create(Compilation compilation, List<INamedTypeSymbol> results)
         {
-            var enabled = false;
+            var vcAttribute = compilation.GetTypeByMetadataName(ViewComponentTypes.ViewComponentAttribute);
-            foreach (var reference in compilation.References)
+            var nonVCAttribute = compilation.GetTypeByMetadataName(ViewComponentTypes.NonViewComponentAttribute);
-            {
-                var symbol = compilation.GetAssemblyOrModuleSymbol(reference) as IAssemblySymbol;
-                if (symbol != null)
-                {
-                    if (string.Equals(symbol.Identity.Name, ViewComponentTypes.Assembly, StringComparison.Ordinal))
-                    {
-                        enabled = symbol.Identity.Version >= ViewComponentTypes.AssemblyVersion;
-                        break;
-                    }
-                }
-            }
-
-            var vcAttribute = enabled ? compilation.GetTypeByMetadataName(ViewComponentTypes.ViewComponentAttribute) : null;
-            var nonVCAttribute = enabled ? compilation.GetTypeByMetadataName(ViewComponentTypes.NonViewComponentAttribute) : null;
             return new ViewComponentTypeVisitor(vcAttribute, nonVCAttribute, results);
         }
 

src/Microsoft.AspNetCore.Mvc.Razor.Extensions/RazorExtensions.cs

@@ -4,6 +4,7 @@
 using System;
 using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.AspNetCore.Razor.Language.Extensions;
+using Microsoft.CodeAnalysis.Razor;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
 {
@@ -25,6 +26,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
             InheritsDirective.Register(builder);
             SectionDirective.Register(builder);
 
+            builder.Features.Add(new DefaultTagHelperDescriptorProvider());
             builder.Features.Add(new ViewComponentTagHelperDescriptorProvider());
 
             builder.AddTargetExtension(new ViewComponentTagHelperTargetExtension());
@@ -61,6 +63,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
             InheritsDirective.Register(builder);
             SectionDirective.Register(builder);
 
+            builder.Features.Add(new DefaultTagHelperDescriptorProvider());
             builder.Features.Add(new ViewComponentTagHelperDescriptorProvider());
 
             builder.AddTargetExtension(new ViewComponentTagHelperTargetExtension());

src/Microsoft.AspNetCore.Mvc.Razor.Extensions/ViewComponentTagHelperDescriptorProvider.cs

@@ -11,10 +11,6 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
 {
     public sealed class ViewComponentTagHelperDescriptorProvider : RazorEngineFeatureBase, ITagHelperDescriptorProvider
     {
-        // Hack for testability. The visitor will normally just no op if we're not referencing
-        // an appropriate version of MVC.
-        internal bool ForceEnabled { get; set; }
-
         public int Order { get; set; }
 
         public void Execute(TagHelperDescriptorProviderContext context)
@@ -33,10 +29,6 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
 
             var types = new List<INamedTypeSymbol>();
             var visitor = ViewComponentTypeVisitor.Create(compilation, types);
-            if (ForceEnabled)
-            {
-                visitor.Enabled = true;
-            }
 
             // We always visit the global namespace.
             visitor.Visit(compilation.Assembly.GlobalNamespace);

src/Microsoft.AspNetCore.Mvc.Razor.Extensions/ViewComponentTypeVisitor.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.Linq;
 using Microsoft.CodeAnalysis;
@@ -29,12 +28,8 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
             _viewComponentAttribute = viewComponentAttribute;
             _nonViewComponentAttribute = nonViewComponentAttribute;
             _results = results;
-
-            Enabled = _viewComponentAttribute != null;
         }
 
-        public bool Enabled { get; set; }
-
         public override void VisitNamedType(INamedTypeSymbol symbol)
         {
             if (IsViewComponent(symbol))
@@ -63,7 +58,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
 
         internal bool IsViewComponent(INamedTypeSymbol symbol)
         {
-            if (!Enabled)
+            if (_viewComponentAttribute == null)
             {
                 return false;
             }

src/Microsoft.AspNetCore.Razor.Language/TagHelperDescriptorProviderContext.cs

@@ -8,6 +8,10 @@ namespace Microsoft.AspNetCore.Razor.Language
 {
     public abstract class TagHelperDescriptorProviderContext
     {
+        public virtual bool ExcludeHidden { get; set; }
+
+        public virtual bool IncludeDocumentation { get; set; }
+
         public abstract ItemCollection Items { get; }
 
         public abstract ICollection<TagHelperDescriptor> Results { get; }

src/Microsoft.CodeAnalysis.Razor.Workspaces/TagHelperResolver.cs

@@ -41,6 +41,8 @@ namespace Microsoft.CodeAnalysis.Razor
 
             var results = new List<TagHelperDescriptor>();
             var context = TagHelperDescriptorProviderContext.Create(results);
+            context.ExcludeHidden = true;
+            context.IncludeDocumentation = true;
 
             var compilation = await project.WorkspaceProject.GetCompilationAsync().ConfigureAwait(false);
             context.SetCompilation(compilation);

src/Microsoft.CodeAnalysis.Razor/DefaultTagHelperDescriptorFactory.cs

@@ -28,9 +28,11 @@ namespace Microsoft.CodeAnalysis.Razor
                 .WithGlobalNamespaceStyle(SymbolDisplayGlobalNamespaceStyle.Omitted)
                 .WithMiscellaneousOptions(SymbolDisplayFormat.FullyQualifiedFormat.MiscellaneousOptions & (~SymbolDisplayMiscellaneousOptions.UseSpecialTypes));
 
-        public DefaultTagHelperDescriptorFactory(Compilation compilation, bool designTime)
+        public DefaultTagHelperDescriptorFactory(Compilation compilation, bool includeDocumentation, bool excludeHidden)
         {
-            DesignTime = designTime;
+            IncludeDocumentation = includeDocumentation;
+            ExcludeHidden = excludeHidden;
+
             _htmlAttributeNameAttributeSymbol = compilation.GetTypeByMetadataName(TagHelperTypes.HtmlAttributeNameAttribute);
             _htmlAttributeNotBoundAttributeSymbol = compilation.GetTypeByMetadataName(TagHelperTypes.HtmlAttributeNotBoundAttribute);
             _htmlTargetElementAttributeSymbol = compilation.GetTypeByMetadataName(TagHelperTypes.HtmlTargetElementAttribute);
@@ -40,7 +42,9 @@ namespace Microsoft.CodeAnalysis.Razor
             _iDictionarySymbol = compilation.GetTypeByMetadataName(TagHelperTypes.IDictionary);
         }
 
-        protected bool DesignTime { get; }
+        protected bool ExcludeHidden { get; }
+
+        protected bool IncludeDocumentation { get; }
 
         /// <inheritdoc />
         public virtual TagHelperDescriptor CreateDescriptor(INamedTypeSymbol type)
@@ -154,7 +158,7 @@ namespace Microsoft.CodeAnalysis.Razor
 
         private void AddDocumentation(INamedTypeSymbol type, TagHelperDescriptorBuilder builder)
         {
-            if (!DesignTime)
+            if (!IncludeDocumentation)
             {
                 return;
             }
@@ -169,10 +173,6 @@ namespace Microsoft.CodeAnalysis.Razor
 
         private void AddTagOutputHint(INamedTypeSymbol type, TagHelperDescriptorBuilder builder)
         {
-            if (!DesignTime)
-            {
-                return;
-            }
             string outputElementHint = null;
             var outputElementHintAttribute = type.GetAttributes().Where(a => a.AttributeClass == _outputElementHintAttributeSymbol).FirstOrDefault();
             if (outputElementHintAttribute != null)
@@ -221,7 +221,7 @@ namespace Microsoft.CodeAnalysis.Razor
                     builder.IsEnum = true;
                 }
 
-                if (DesignTime)
+                if (IncludeDocumentation)
                 {
                     var xml = property.GetDocumentationCommentXml();
 
@@ -416,7 +416,7 @@ namespace Microsoft.CodeAnalysis.Razor
 
         private bool ShouldSkipDescriptorCreation(ISymbol symbol)
         {
-            if (DesignTime)
+            if (ExcludeHidden)
             {
                 var editorBrowsableAttribute = symbol.GetAttributes().Where(a => a.AttributeClass == _editorBrowsableAttributeSymbol).FirstOrDefault();
 

src/Microsoft.CodeAnalysis.Razor/DefaultTagHelperDescriptorProvider.cs

@@ -9,6 +9,10 @@ namespace Microsoft.CodeAnalysis.Razor
 {
     public sealed class DefaultTagHelperDescriptorProvider : RazorEngineFeatureBase, ITagHelperDescriptorProvider
     {
+        [Obsolete(
+            "This property is obsolete will not be honored. Documentation will be included if " +
+            "TagHelperDescriptorProviderContext.IncludeDocumentation is set to true. Hidden tag helpers will" +
+            "be excluded from the results if TagHelperDescriptorProviderContext.ExcludeHidden is set to true.")]
         public bool DesignTime { get; set; }
 
         public int Order { get; set; }
@@ -44,7 +48,7 @@ namespace Microsoft.CodeAnalysis.Razor
                 }
             }
 
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, DesignTime);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, context.IncludeDocumentation, context.ExcludeHidden);
             for (var i = 0; i < types.Count; i++)
             {
                 var descriptor = factory.CreateDescriptor(types[i]);

src/Microsoft.CodeAnalysis.Remote.Razor/RemoteTagHelperResolver.cs

@@ -53,11 +53,7 @@ namespace Microsoft.CodeAnalysis.Razor
             //
             // Most notably, we are going to find the Tag Helpers using a compilation, and we have
             // no editor settings.
-            Action<RazorProjectEngineBuilder> configure = (b) =>
+            //
-            {
-                b.Features.Add(new DefaultTagHelperDescriptorProvider() { DesignTime = true });
-            };
-
             // The default configuration currently matches MVC-2.0. Beyond MVC-2.0 we added SDK support for 
             // properly detecting project versions, so that's a good version to assume when we can't find a
             // configuration.
@@ -68,7 +64,7 @@ namespace Microsoft.CodeAnalysis.Razor
             // This will stop a crash from happening in this case (misconfigured project), but will still make
             // it obvious to the user that something is wrong.
             var factory = CreateFactory(configuration, factoryTypeName) ?? _fallbackFactory;
-            return factory.Create(configuration, RazorProjectFileSystem.Empty, configure);
+            return factory.Create(configuration, RazorProjectFileSystem.Empty, b => { });
         }
 
         private IProjectEngineFactory CreateFactory(RazorConfiguration configuration, string factoryTypeName)

src/Microsoft.VisualStudio.Editor.Razor/DefaultTagHelperResolver.cs

@@ -36,10 +36,7 @@ namespace Microsoft.VisualStudio.Editor.Razor
                 return Task.FromResult(TagHelperResolutionResult.Empty);
             }
 
-            var engine = _engineFactory.Create(project, RazorProjectFileSystem.Empty, b => 
+            var engine = _engineFactory.Create(project, RazorProjectFileSystem.Empty, b => { });
-            {
-                b.Features.Add(new DefaultTagHelperDescriptorProvider() { DesignTime = true, });
-            });
             return GetTagHelpersAsync(project, engine);
         }
     }

test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/IntegrationTests/CodeGenerationIntegrationTest.cs

@@ -4,7 +4,6 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
-using System.Reflection;
 using System.Text.RegularExpressions;
 using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.AspNetCore.Razor.Language.IntegrationTests;
@@ -13,22 +12,22 @@ using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.Emit;
 using Microsoft.CodeAnalysis.Razor;
-using Microsoft.Extensions.DependencyModel;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.IntegrationTests
 {
     public class CodeGenerationIntegrationTest : IntegrationTestBase
     {
-        private const string CurrentMvcShim = "Microsoft.AspNetCore.Razor.Test.MvcShim.dll";
         private static readonly RazorSourceDocument DefaultImports = MvcRazorTemplateEngine.GetDefaultImports();
 
+        private CSharpCompilation BaseCompilation => MvcShim.BaseCompilation.WithAssemblyName("AppCode");
+
         #region Runtime
         [Fact]
         public void InvalidNamespaceAtEOF_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
@@ -39,9 +38,9 @@ public class MyService<TModel>
 {
     public string Html { get; set; }
 }";
-            var compilationReferences = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
 
-            RunRuntimeTest(compilationReferences);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
@@ -63,9 +62,9 @@ public class MyModel
 
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
 
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
@@ -87,44 +86,50 @@ public class MyModel
 {
 
 }";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
 
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void MalformedPageDirective_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunRuntimeTest(references);
+
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void Basic_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunRuntimeTest(references);
+
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void Sections_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 
 public class InputTestTagHelper : {typeof(TagHelper).FullName}
 {{
     public ModelExpression For {{ get; set; }}
 }}
-");
+";
-            RunRuntimeTest(references);
+
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void _ViewImports_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunRuntimeTest(references);
+
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
@@ -136,9 +141,9 @@ public class MyApp
     public string MyProperty { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
 
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
@@ -159,9 +164,9 @@ public class MyApp
 {
     public string MyProperty { get; set; }
 }";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
 
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
@@ -183,75 +188,81 @@ public class MyService<TModel>
     public string Html { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
 
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void Model_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
 
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void ModelExpressionTagHelper_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 
 public class InputTestTagHelper : {typeof(TagHelper).FullName}
 {{
     public ModelExpression For {{ get; set; }}
 }}
-");
+";
-            RunRuntimeTest(references);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void RazorPages_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 public class DivTagHelper : {typeof(TagHelper).FullName}
 {{
 
 }}
-");
+";
-            RunRuntimeTest(references);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void RazorPagesWithoutModel_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 public class DivTagHelper : {typeof(TagHelper).FullName}
 {{
 
 }}
-");
+";
-            RunRuntimeTest(references);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void PageWithNamespace_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void ViewWithNamespace_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunRuntimeTest(references);
+            RunRuntimeTest(compilation);
         }
 
         [Fact]
         public void ViewComponentTagHelper_Runtime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 public class TestViewComponent
 {{
     public string Invoke(string firstName)
@@ -265,8 +276,11 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
 {{
     public string Bar {{ get; set; }}
 }}
-");
+";
-            RunRuntimeTest(references);
+
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+            
+            RunRuntimeTest(compilation);
         }
         #endregion
 
@@ -274,8 +288,8 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
         [Fact]
         public void InvalidNamespaceAtEOF_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -288,8 +302,9 @@ public class MyService<TModel>
 }
 ";
 
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -312,8 +327,9 @@ public class MyModel
 
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -337,43 +353,47 @@ public abstract class MyPageModel<T> : Page
 }
 ";
 
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void MalformedPageDirective_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void Basic_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void Sections_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 
 public class InputTestTagHelper : {typeof(TagHelper).FullName}
 {{
     public ModelExpression For {{ get; set; }}
 }}
-");
+";
-            RunDesignTimeTest(references);
+
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void _ViewImports_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -385,8 +405,9 @@ public class MyApp
     public string MyProperty { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -408,8 +429,9 @@ public class MyApp
     public string MyProperty { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -431,15 +453,16 @@ public class MyApp
     public string MyProperty { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void Model_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -451,66 +474,74 @@ public class ThisShouldBeGenerated
 
 }";
 
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+
+            RunDesignTimeTest(compilation);
         }
         
         [Fact]
         public void ModelExpressionTagHelper_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 
 public class InputTestTagHelper : {typeof(TagHelper).FullName}
 {{
     public ModelExpression For {{ get; set; }}
 }}
-");
+";
-            RunDesignTimeTest(references);
+
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void RazorPages_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 public class DivTagHelper : {typeof(TagHelper).FullName}
 {{
 
 }}
-");
+";
-            RunDesignTimeTest(references);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void RazorPagesWithoutModel_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 public class DivTagHelper : {typeof(TagHelper).FullName}
 {{
 
 }}
-");
+";
-            RunDesignTimeTest(references);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void PageWithNamespace_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void ViewWithNamespace_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void ViewComponentTagHelper_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 public class TestViewComponent
 {{
     public string Invoke(string firstName)
@@ -524,17 +555,22 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
 {{
     public string Bar {{ get; set; }}
 }}
-");
+";
-            RunDesignTimeTest(references);
+
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+            
+            RunDesignTimeTest(compilation);
         }
         #endregion
 
         private void RunRuntimeTest(
-            IEnumerable<MetadataReference> compilationReferences,
+            CSharpCompilation baseCompilation,
             IEnumerable<string> expectedErrors = null)
         {
+            Assert.Empty(baseCompilation.GetDiagnostics());
+
             // Arrange
-            var engine = CreateRuntimeEngine(compilationReferences);
+            var engine = CreateRuntimeEngine(baseCompilation);
             var document = CreateCodeDocument();
 
             // Act
@@ -543,15 +579,17 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
             // Assert
             AssertDocumentNodeMatchesBaseline(document.GetDocumentIntermediateNode());
             AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
-            AssertDocumentCompiles(document, compilationReferences, expectedErrors);
+            AssertDocumentCompiles(document, baseCompilation, expectedErrors);
         }
 
         private void RunDesignTimeTest(
-            IEnumerable<MetadataReference> compilationReferences,
+            CSharpCompilation baseCompilation,
             IEnumerable<string> expectedErrors = null)
         {
+            Assert.Empty(baseCompilation.GetDiagnostics());
+
             // Arrange
-            var engine = CreateDesignTimeEngine(compilationReferences);
+            var engine = CreateDesignTimeEngine(baseCompilation);
             var document = CreateCodeDocument();
 
             // Act
@@ -561,25 +599,21 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
             AssertDocumentNodeMatchesBaseline(document.GetDocumentIntermediateNode());
             AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
             AssertSourceMappingsMatchBaseline(document);
-            AssertDocumentCompiles(document, compilationReferences, expectedErrors);
+            AssertDocumentCompiles(document, baseCompilation, expectedErrors);
-        }
-
-        private static IEnumerable<MetadataReference> CreateCompilationReferences(string mvcShimName, string appCode = null)
-        {
-            var shimReferences = CreateMvcShimReferences(mvcShimName);
-            return CreateAppCodeReferences(appCode, shimReferences);
         }
 
         private void AssertDocumentCompiles(
             RazorCodeDocument document,
-            IEnumerable<MetadataReference> compilationReferences,
+            CSharpCompilation baseCompilation,
             IEnumerable<string> expectedErrors = null)
         {
             var cSharp = document.GetCSharpDocument().GeneratedCode;
 
             var syntaxTree = CSharpSyntaxTree.ParseText(cSharp);
             var options = new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary);
-            var compilation = CSharpCompilation.Create("CodeGenerationTestAssembly", new[] { syntaxTree }, compilationReferences, options);
+
+            var references = baseCompilation.References.Concat(new[] { baseCompilation.ToMetadataReference() });
+            var compilation = CSharpCompilation.Create("CodeGenerationTestAssembly", new[] { syntaxTree }, references, options);
 
             var diagnostics = compilation.GetDiagnostics();
 
@@ -595,29 +629,29 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
             }
         }
 
-        protected RazorEngine CreateDesignTimeEngine(IEnumerable<MetadataReference> references)
+        protected RazorEngine CreateDesignTimeEngine(CSharpCompilation compilation)
         {
+            var references = compilation.References.Concat(new[] { compilation.ToMetadataReference() });
+
             return RazorEngine.CreateDesignTime(b =>
             {
                 RazorExtensions.Register(b);
 
                 b.Features.Add(GetMetadataReferenceFeature(references));
                 b.Features.Add(new CompilationTagHelperFeature());
-                b.Features.Add(new DefaultTagHelperDescriptorProvider() { DesignTime = true });
-                b.Features.Add(new ViewComponentTagHelperDescriptorProvider() { ForceEnabled = true });
             });
         }
 
-        protected RazorEngine CreateRuntimeEngine(IEnumerable<MetadataReference> references)
+        protected RazorEngine CreateRuntimeEngine(CSharpCompilation compilation)
         {
+            var references = compilation.References.Concat(new[] { compilation.ToMetadataReference() });
+
             return RazorEngine.Create(b =>
             {
                 RazorExtensions.Register(b);
 
                 b.Features.Add(GetMetadataReferenceFeature(references));
                 b.Features.Add(new CompilationTagHelperFeature());
-                b.Features.Add(new DefaultTagHelperDescriptorProvider() { DesignTime = true });
-                b.Features.Add(new ViewComponentTagHelperDescriptorProvider() { ForceEnabled = true });
             });
         }
 
@@ -664,48 +698,5 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
                 References = references.ToList()
             };
         }
-
-        private static IEnumerable<MetadataReference> CreateAppCodeReferences(string appCode, IEnumerable<MetadataReference> shimReferences)
-        {
-            var references = new List<MetadataReference>(shimReferences);
-
-            if (appCode != null)
-            {
-                var appCodeSyntaxTrees = new List<SyntaxTree> { CSharpSyntaxTree.ParseText(appCode) };
-
-                var compilation = CSharpCompilation.Create(
-                    "AppCode",
-                    appCodeSyntaxTrees,
-                    shimReferences,
-                    options: new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary));
-                var stream = new MemoryStream();
-                var compilationResult = compilation.Emit(stream, options: new EmitOptions());
-                stream.Position = 0;
-
-                var diagString = string.Join(";", compilationResult.Diagnostics.Where(s => s.Severity == DiagnosticSeverity.Error).Select(s => s.ToString()));
-                Assert.True(compilationResult.Success, string.Format("Application code needed for tests didn't compile!: {0}", diagString));
-
-                references.Add(MetadataReference.CreateFromStream(stream));
-            }
-
-            return references;
-        }
-
-        private static IEnumerable<MetadataReference> CreateMvcShimReferences(string mvcShimName)
-        {
-            var dllPath = Path.Combine(Directory.GetCurrentDirectory(), mvcShimName);
-            var assembly = Assembly.LoadFile(dllPath);
-            var assemblyDependencyContext = DependencyContext.Load(assembly);
-
-            var assemblyReferencePaths = assemblyDependencyContext.CompileLibraries.SelectMany(l => l.ResolveReferencePaths());
-
-            var references = assemblyReferencePaths
-                .Select(assemblyPath => MetadataReference.CreateFromFile(assemblyPath))
-                .ToList<MetadataReference>();
-
-            Assert.NotEmpty(references);
-
-            return references;
-        }
     }
 }

test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/MvcShim.cs

@@ -0,0 +1,45 @@
+// 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.IO;
+using System.Reflection;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
+{
+    internal static class MvcShim
+    {
+        public static readonly string AssemblyName = "Microsoft.AspNetCore.Razor.Test.MvcShim";
+
+        private static Assembly _assembly;
+        private static CSharpCompilation _baseCompilation;
+
+        public static Assembly Assembly
+        {
+            get
+            {
+                if (_assembly == null)
+                {
+                    var filePath = Path.Combine(Directory.GetCurrentDirectory(), AssemblyName + ".dll");
+                    _assembly = Assembly.LoadFrom(filePath);
+                }
+
+                return _assembly;
+            }
+        }
+
+        public static CSharpCompilation BaseCompilation
+        {
+            get
+            {
+                if (_baseCompilation == null)
+                {
+                    _baseCompilation = TestCompilation.Create(Assembly);
+                }
+
+                return _baseCompilation;
+            }
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/ViewComponentTagHelperDescriptorProviderTest.cs

@@ -1,6 +1,7 @@
 // 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.IO;
 using System.Linq;
 using System.Reflection;
 using Microsoft.AspNetCore.Razor.Language;
@@ -14,8 +15,6 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
     // This is just a basic integration test. There are detailed tests for the VCTH visitor and descriptor factory.
     public class ViewComponentTagHelperDescriptorProviderTest
     {
-        private static readonly Assembly _assembly = typeof(ViewComponentTagHelperDescriptorProviderTest).GetTypeInfo().Assembly;
-
         [Fact]
         public void DescriptorProvider_FindsVCTH()
         {
@@ -27,15 +26,14 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
         }
 ";
 
-            var testCompilation = TestCompilation.Create(_assembly, CSharpSyntaxTree.ParseText(code));
+            var compilation = MvcShim.BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(code));
 
             var context = TagHelperDescriptorProviderContext.Create();
-            context.SetCompilation(testCompilation);
+            context.SetCompilation(compilation);
 
             var provider = new ViewComponentTagHelperDescriptorProvider()
             {
                 Engine = RazorEngine.CreateEmpty(b => { }),
-                ForceEnabled = true,
             };
 
             var expectedDescriptor = TagHelperDescriptorBuilder.Create(
@@ -68,8 +66,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
             provider.Execute(context);
 
             // Assert
-            var descriptor = context.Results.FirstOrDefault(d => TagHelperDescriptorComparer.CaseSensitive.Equals(d, expectedDescriptor));
+            Assert.Single(context.Results, d => TagHelperDescriptorComparer.CaseSensitive.Equals(d, expectedDescriptor));
-            Assert.NotNull(descriptor);
         }
     }
 }

test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X.Test/IntegrationTests/CodeGenerationIntegrationTest.cs

@@ -20,14 +20,15 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X.IntegrationTests
 {
     public class CodeGenerationIntegrationTest : IntegrationTestBase
     {
-        private const string CurrentMvcShim = "Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X.dll";
         private static readonly RazorSourceDocument DefaultImports = MvcRazorTemplateEngine.GetDefaultImports();
 
+        private CSharpCompilation BaseCompilation => MvcShim.BaseCompilation.WithAssemblyName("AppCode");
+
         [Fact]
         public void InvalidNamespaceAtEOF_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -40,8 +41,8 @@ public class MyService<TModel>
 }
 ";
 
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -64,8 +65,8 @@ public class MyModel
 
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -89,36 +90,39 @@ public class MyModel
 }
 ";
 
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void Basic_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void Sections_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 
 public class InputTestTagHelper : {typeof(TagHelper).FullName}
 {{
     public ModelExpression For {{ get; set; }}
 }}
-");
+";
-            RunDesignTimeTest(references);
+
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void _ViewImports_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -130,8 +134,8 @@ public class MyApp
     public string MyProperty { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -153,8 +157,8 @@ public class MyApp
     public string MyProperty { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -176,15 +180,15 @@ public class MyApp
     public string MyProperty { get; set; }
 }
 ";
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void Model_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim);
+            var compilation = BaseCompilation;
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
@@ -196,28 +200,30 @@ public class ThisShouldBeGenerated
 
 }";
 
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
-            RunDesignTimeTest(references);
+            RunDesignTimeTest(compilation);
         }
         
         [Fact]
         public void ModelExpressionTagHelper_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 
 public class InputTestTagHelper : {typeof(TagHelper).FullName}
 {{
     public ModelExpression For {{ get; set; }}
 }}
-");
+";
-            RunDesignTimeTest(references);
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunDesignTimeTest(compilation);
         }
 
         [Fact]
         public void ViewComponentTagHelper_DesignTime()
         {
-            var references = CreateCompilationReferences(CurrentMvcShim, appCode: $@"
+            var appCode = $@"
 public class TestViewComponent
 {{
     public string Invoke(string firstName)
@@ -231,16 +237,21 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
 {{
     public string Bar {{ get; set; }}
 }}
-");
+";
-            RunDesignTimeTest(references);
+
+            var compilation = BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(appCode));
+
+            RunDesignTimeTest(compilation);
         }
 
         private void RunDesignTimeTest(
-            IEnumerable<MetadataReference> compilationReferences,
+            CSharpCompilation baseCompilation,
             IEnumerable<string> expectedErrors = null)
         {
+            Assert.Empty(baseCompilation.GetDiagnostics());
+            
             // Arrange
-            var engine = CreateDesignTimeEngine(compilationReferences);
+            var engine = CreateDesignTimeEngine(baseCompilation);
             var document = CreateCodeDocument();
 
             // Act
@@ -250,25 +261,21 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
             AssertDocumentNodeMatchesBaseline(document.GetDocumentIntermediateNode());
             AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
             AssertSourceMappingsMatchBaseline(document);
-            AssertDocumentCompiles(document, compilationReferences, expectedErrors);
+            AssertDocumentCompiles(document, baseCompilation, expectedErrors);
-        }
-
-        private static IEnumerable<MetadataReference> CreateCompilationReferences(string mvcShimName, string appCode = null)
-        {
-            var shimReferences = CreateMvcShimReferences(mvcShimName);
-            return CreateAppCodeReferences(appCode, shimReferences);
         }
 
         private void AssertDocumentCompiles(
             RazorCodeDocument document,
-            IEnumerable<MetadataReference> compilationReferences,
+            CSharpCompilation baseCompilation,
             IEnumerable<string> expectedErrors = null)
         {
             var cSharp = document.GetCSharpDocument().GeneratedCode;
 
             var syntaxTree = CSharpSyntaxTree.ParseText(cSharp);
             var options = new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary);
-            var compilation = CSharpCompilation.Create("CodeGenerationTestAssembly", new[] { syntaxTree }, compilationReferences, options);
+
+            var references = baseCompilation.References.Concat(new[] { baseCompilation.ToMetadataReference() });
+            var compilation = CSharpCompilation.Create("CodeGenerationTestAssembly", new[] { syntaxTree }, references, options);
 
             var diagnostics = compilation.GetDiagnostics();
 
@@ -284,8 +291,10 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
             }
         }
 
-        protected RazorEngine CreateDesignTimeEngine(IEnumerable<MetadataReference> references)
+        protected RazorEngine CreateDesignTimeEngine(CSharpCompilation compilation)
         {
+            var references = compilation.References.Concat(new[] { compilation.ToMetadataReference() });
+
             return RazorEngine.CreateDesignTime(b =>
             {
                 RazorExtensions.Register(b);
@@ -293,8 +302,6 @@ public class AllTagHelper : {typeof(TagHelper).FullName}
 
                 b.Features.Add(GetMetadataReferenceFeature(references));
                 b.Features.Add(new CompilationTagHelperFeature());
-                b.Features.Add(new DefaultTagHelperDescriptorProvider() { DesignTime = true });
-                b.Features.Add(new ViewComponentTagHelperDescriptorProvider() { ForceEnabled = true });
             });
         }
 

test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X.Test/MvcShim.cs

@@ -0,0 +1,45 @@
+// 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.IO;
+using System.Reflection;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
+{
+    internal static class MvcShim
+    {
+        public static readonly string AssemblyName = "Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X";
+
+        private static Assembly _assembly;
+        private static CSharpCompilation _baseCompilation;
+
+        public static Assembly Assembly
+        {
+            get
+            {
+                if (_assembly == null)
+                {
+                    var filePath = Path.Combine(Directory.GetCurrentDirectory(), AssemblyName + ".dll");
+                    _assembly = Assembly.LoadFrom(filePath);
+                }
+
+                return _assembly;
+            }
+        }
+
+        public static CSharpCompilation BaseCompilation
+        {
+            get
+            {
+                if (_baseCompilation == null)
+                {
+                    _baseCompilation = TestCompilation.Create(Assembly);
+                }
+
+                return _baseCompilation;
+            }
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X.Test/ViewComponentTagHelperDescriptorProviderTest.cs

@@ -14,8 +14,6 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
     // This is just a basic integration test. There are detailed tests for the VCTH visitor and descriptor factory.
     public class ViewComponentTagHelperDescriptorProviderTest
     {
-        private static readonly Assembly _assembly = typeof(ViewComponentTagHelperDescriptorProviderTest).GetTypeInfo().Assembly;
-
         [Fact]
         public void DescriptorProvider_FindsVCTH()
         {
@@ -27,15 +25,14 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
         }
 ";
 
-            var testCompilation = TestCompilation.Create(_assembly, CSharpSyntaxTree.ParseText(code));
+            var compilation = MvcShim.BaseCompilation.AddSyntaxTrees(CSharpSyntaxTree.ParseText(code));
 
             var context = TagHelperDescriptorProviderContext.Create();
-            context.SetCompilation(testCompilation);
+            context.SetCompilation(compilation);
 
             var provider = new ViewComponentTagHelperDescriptorProvider()
             {
                 Engine = RazorEngine.CreateEmpty(b => { }),
-                ForceEnabled = true,
             };
 
             var expectedDescriptor = TagHelperDescriptorBuilder.Create(
@@ -68,8 +65,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
             provider.Execute(context);
 
             // Assert
-            var descriptor = context.Results.FirstOrDefault(d => TagHelperDescriptorComparer.CaseSensitive.Equals(d, expectedDescriptor));
+            Assert.Single(context.Results, d => TagHelperDescriptorComparer.CaseSensitive.Equals(d, expectedDescriptor));
-            Assert.NotNull(descriptor);
         }
     }
 }

test/Microsoft.AspNetCore.Razor.Test.Common/TestCompilation.cs

@@ -32,7 +32,7 @@ namespace Microsoft.CodeAnalysis
 
         public static string AssemblyName => "TestAssembly";
 
-        public static Compilation Create(Assembly assembly, SyntaxTree syntaxTree = null)
+        public static CSharpCompilation Create(Assembly assembly, SyntaxTree syntaxTree = null)
         {
             IEnumerable<SyntaxTree> syntaxTrees = null;
 
@@ -47,7 +47,7 @@ namespace Microsoft.CodeAnalysis
                 _referenceCache.TryAdd(assembly, metadataReferences);
             }
 
-            var compilation = CSharpCompilation.Create(AssemblyName, syntaxTrees, metadataReferences);
+            var compilation = CSharpCompilation.Create(AssemblyName, syntaxTrees, metadataReferences, new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary));
 
             EnsureValidCompilation(compilation);
 

test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X/Microsoft.AspNetCore.Mvc/ViewComponentAttribute.cs

@@ -0,0 +1,11 @@
+// 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;
+
+namespace Microsoft.AspNetCore.Mvc
+{
+    public sealed class ViewComponentAttribute : Attribute
+    {
+    }
+}

test/Microsoft.AspNetCore.Razor.Test.MvcShim/Microsoft.AspNetCore.Mvc/ViewComponentAttribute.cs

@@ -0,0 +1,11 @@
+// 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;
+
+namespace Microsoft.AspNetCore.Mvc
+{
+    public sealed class ViewComponentAttribute : Attribute
+    {
+    }
+}

test/Microsoft.CodeAnalysis.Razor.Test/DefaultTagHelperDescriptorFactoryTest.cs

@@ -392,7 +392,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             TagHelperDescriptor expectedDescriptor)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -443,7 +443,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             TagHelperDescriptor expectedDescriptor)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -499,7 +499,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             TagHelperDescriptor expectedDescriptor)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -559,7 +559,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             TagHelperDescriptor expectedDescriptor)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -734,7 +734,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             TagHelperDescriptor expectedDescriptor)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime, designTime);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -931,7 +931,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             TagHelperDescriptor expectedDescriptor)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -968,7 +968,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             string expectedAttributeName)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -1005,7 +1005,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                             .PropertyName(validProperty2.Name)
                             .TypeName(validProperty2.PropertyType.FullName),
                     });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(OverriddenAttributeTagHelper).FullName);
 
             // Act
@@ -1039,7 +1039,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                             .PropertyName(validProperty2.Name)
                             .TypeName(validProperty2.PropertyType.FullName),
                     });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(InheritedOverriddenAttributeTagHelper).FullName);
 
             // Act
@@ -1073,7 +1073,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                             .PropertyName(validProperty2.Name)
                             .TypeName(validProperty2.PropertyType.FullName),
                     });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(InheritedNotOverriddenAttributeTagHelper).FullName);
 
             // Act
@@ -1098,7 +1098,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                         .PropertyName(nameof(InheritedSingleAttributeTagHelper.IntAttribute))
                         .TypeName(typeof(int).FullName)
                 });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(InheritedSingleAttributeTagHelper).FullName);
 
             // Act
@@ -1124,7 +1124,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                         .PropertyName(intProperty.Name)
                         .TypeName(intProperty.PropertyType.FullName)
                 });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(SingleAttributeTagHelper).FullName);
 
             // Act
@@ -1151,7 +1151,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                         .PropertyName(validProperty.Name)
                         .TypeName(validProperty.PropertyType.FullName)
                 });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(MissingAccessorTagHelper).FullName);
 
             // Act
@@ -1178,7 +1178,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                         .PropertyName(validProperty.Name)
                         .TypeName(validProperty.PropertyType.FullName)
                 });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(NonPublicAccessorTagHelper).FullName);
 
             // Act
@@ -1203,7 +1203,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                         .PropertyName(nameof(NotBoundAttributeTagHelper.BoundProperty))
                         .TypeName(typeof(object).FullName)
                 });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(NotBoundAttributeTagHelper).FullName);
 
             // Act
@@ -1234,7 +1234,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                         builder => builder.RequireTagName("p"),
                         builder => builder.RequireTagName("div"),
                     });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(MultiTagTagHelper).FullName);
 
             // Act
@@ -1260,7 +1260,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                             .PropertyName(validProp.Name)
                             .TypeName(validProp.PropertyType.FullName),
                     });
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(InheritedMultiTagTagHelper).FullName);
 
             // Act
@@ -1284,7 +1284,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                     builder => builder.RequireTagName("div"),
                 });
 
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(DuplicateTagNameTagHelper).FullName);
 
             // Act
@@ -1303,7 +1303,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
                     "data-condition",
                     typeof(OverrideNameTagHelper).FullName,
                     AssemblyName);
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(OverrideNameTagHelper).FullName);
 
             // Act
@@ -1345,7 +1345,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
             var tagHelperType = compilation.GetTypeByMetadataName("DynamicTestTagHelper");
             var attribute = tagHelperType.GetAttributes().Single();
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: false, excludeHidden: false);
 
             // Act
             var descriptor = factory.CreateDescriptor(tagHelperType);
@@ -1366,21 +1366,21 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             {
                 // name, expectedNames
                 return new TheoryData<string, IEnumerable<string>>
-                        {
+                {
-                            { "p", new[] { "p" } },
+                    { "p", new[] { "p" } },
-                            { " p", new[] { "p" } },
+                    { " p", new[] { "p" } },
-                            { "p ", new[] { "p" } },
+                    { "p ", new[] { "p" } },
-                            { " p ", new[] { "p" } },
+                    { " p ", new[] { "p" } },
-                            { "p,div", new[] { "p", "div" } },
+                    { "p,div", new[] { "p", "div" } },
-                            { " p,div", new[] { "p", "div" } },
+                    { " p,div", new[] { "p", "div" } },
-                            { "p ,div", new[] { "p", "div" } },
+                    { "p ,div", new[] { "p", "div" } },
-                            { " p ,div", new[] { "p", "div" } },
+                    { " p ,div", new[] { "p", "div" } },
-                            { "p, div", new[] { "p", "div" } },
+                    { "p, div", new[] { "p", "div" } },
-                            { "p,div ", new[] { "p", "div" } },
+                    { "p,div ", new[] { "p", "div" } },
-                            { "p, div ", new[] { "p", "div" } },
+                    { "p, div ", new[] { "p", "div" } },
-                            { " p, div ", new[] { "p", "div" } },
+                    { " p, div ", new[] { "p", "div" } },
-                            { " p , div ", new[] { "p", "div" } },
+                    { " p , div ", new[] { "p", "div" } },
-                        };
+                };
             }
         }
 
@@ -1477,7 +1477,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             IEnumerable<BoundAttributeDescriptor> expectedAttributeDescriptors)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(type.FullName);
 
             // Act
@@ -1527,7 +1527,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             var syntaxTree = CSharpSyntaxTree.ParseText(text);
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
             var tagHelperType = compilation.GetTypeByMetadataName("DynamicTestTagHelper");
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: false, excludeHidden: false);
 
             // Act
             var descriptor = factory.CreateDescriptor(tagHelperType);
@@ -1567,7 +1567,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             var syntaxTree = CSharpSyntaxTree.ParseText(text);
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
             var tagHelperType = compilation.GetTypeByMetadataName("DynamicTestTagHelper");
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: false, excludeHidden: false);
 
             // Act
             var descriptor = factory.CreateDescriptor(tagHelperType);
@@ -1610,7 +1610,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             var syntaxTree = CSharpSyntaxTree.ParseText(text);
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
             var tagHelperType = compilation.GetTypeByMetadataName("DynamicTestTagHelper");
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: false, excludeHidden: false);
 
             // Act
             var descriptor = factory.CreateDescriptor(tagHelperType);
@@ -1656,7 +1656,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             var syntaxTree = CSharpSyntaxTree.ParseText(text);
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
             var tagHelperType = compilation.GetTypeByMetadataName("DynamicTestTagHelper");
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: false, excludeHidden: false);
 
             // Act
             var descriptor = factory.CreateDescriptor(tagHelperType);
@@ -1698,7 +1698,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             var syntaxTree = CSharpSyntaxTree.ParseText(text);
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
             var tagHelperType = compilation.GetTypeByMetadataName("DynamicTestTagHelper");
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: false, excludeHidden: false);
 
             // Act
             var descriptor = factory.CreateDescriptor(tagHelperType);
@@ -1739,7 +1739,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             var syntaxTree = CSharpSyntaxTree.ParseText(text);
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
             var tagHelperType = compilation.GetTypeByMetadataName("DynamicTestTagHelper");
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: false, excludeHidden: false);
 
             // Act
             var descriptor = factory.CreateDescriptor(tagHelperType);
@@ -1754,7 +1754,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
         {
             // Arrange
             var objectAssemblyName = typeof(Enumerable).GetTypeInfo().Assembly.GetName().Name;
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(typeof(Enumerable).FullName);
             var expectedDescriptor =
                 CreateTagHelperDescriptor("enumerable", "System.Linq.Enumerable", typeSymbol.ContainingAssembly.Identity.Name);
@@ -2010,7 +2010,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             IEnumerable<RazorDiagnostic> expectedDiagnostics)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: false);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -2069,12 +2069,12 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
 
         [Theory]
         [MemberData(nameof(TagOutputHintData))]
-        public void CreateDescriptor_CreatesDesignTimeDescriptorsWithOutputElementHint(
+        public void CreateDescriptor_CreatesDescriptorsWithOutputElementHint(
             Type tagHelperType,
             TagHelperDescriptor expectedDescriptor)
         {
             // Arrange
-            var factory = new DefaultTagHelperDescriptorFactory(Compilation, designTime: true);
+            var factory = new DefaultTagHelperDescriptorFactory(Compilation, includeDocumentation: false, excludeHidden: false);
             var typeSymbol = Compilation.GetTypeByMetadataName(tagHelperType.FullName);
 
             // Act
@@ -2102,7 +2102,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
         {
         }");
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: true);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: true, excludeHidden: false);
             var typeSymbol = compilation.GetTypeByMetadataName("DocumentedTagHelper");
             var expectedDocumentation =
 @"<member name=""T:DocumentedTagHelper"">
@@ -2151,7 +2151,7 @@ namespace Microsoft.CodeAnalysis.Razor.Workspaces
             public List<bool> RemarksAndSummaryProperty { get; set; }
         }");
             var compilation = TestCompilation.Create(_assembly, syntaxTree);
-            var factory = new DefaultTagHelperDescriptorFactory(compilation, designTime: true);
+            var factory = new DefaultTagHelperDescriptorFactory(compilation, includeDocumentation: true, excludeHidden: false);
             var typeSymbol = compilation.GetTypeByMetadataName("DocumentedTagHelper");
             var expectedDocumentations = new[]
             {

test/Microsoft.CodeAnalysis.Razor.Test/DefaultTagHelperDescriptorProviderTest.cs

@@ -18,11 +18,10 @@ namespace Microsoft.CodeAnalysis.Razor
             // Arrange
             var editorBrowsableTypeName = "Microsoft.CodeAnalysis.Razor.Workspaces.Test.EditorBrowsableTagHelper";
             var compilation = TestCompilation.Create(_assembly);
-            var descriptorProvider = new DefaultTagHelperDescriptorProvider()
+            var descriptorProvider = new DefaultTagHelperDescriptorProvider();
-            {
+
-                DesignTime = true,
-            };
             var context = TagHelperDescriptorProviderContext.Create();
+            context.ExcludeHidden = true;
 
             // Act 
             descriptorProvider.Execute(context);

test/Microsoft.VisualStudio.Editor.Razor.Test/DefaultProjectEngineFactoryServiceTest.cs

@@ -187,6 +187,7 @@ namespace Microsoft.VisualStudio.Editor.Razor
 
             // Assert
             Assert.Single(engine.Engine.Features.OfType<MyCoolNewFeature>());
+            Assert.Single(engine.Engine.Features.OfType<DefaultTagHelperDescriptorProvider>());
             Assert.Single(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperDescriptorProvider>());
             Assert.Single(engine.Engine.Features.OfType<MvcLatest.MvcViewDocumentClassifierPass>());
             Assert.Single(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperPass>());