Fix dependency to aspnet/AspNetCore-Tooling (#170)

* Remove unused package versions
* Remove references to Html.Abstractions
Removing this package since it's from the aspnet/AspNetCore.

* Remove System.ValueTuple package inside remove
* Add versions.details.xml items from corefx
* Add Microsoft.NETCore.App
* Fill up Version.Details.xml
* Update dependencies
* Fix failing test

eng/Version.Details.xml

@@ -1,7 +1,44 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Dependencies>
-  <ProductDependencies></ProductDependencies>
+  <ProductDependencies>
+    <Dependency Name="Microsoft.Extensions.CommandLineUtils.Sources" Version="3.0.0-preview.19074.2">
+      <Uri>https://github.com/aspnet/Extensions</Uri>
+      <Sha>0de62ae930da31048ba7e54c8cd0c6c0bcbd9095</Sha>
+    </Dependency>
+    <Dependency Name="Microsoft.Extensions.HashCodeCombiner.Sources" Version="3.0.0-preview.19074.2">
+      <Uri>https://github.com/aspnet/Extensions</Uri>
+      <Sha>0de62ae930da31048ba7e54c8cd0c6c0bcbd9095</Sha>
+    </Dependency>
+    <Dependency Name="Microsoft.Extensions.NonCapturingTimer.Sources" Version="3.0.0-preview.19074.2">
+      <Uri>https://github.com/aspnet/Extensions</Uri>
+      <Sha>0de62ae930da31048ba7e54c8cd0c6c0bcbd9095</Sha>
+    </Dependency>
+    <Dependency Name="System.Diagnostics.DiagnosticSource" Version="4.6.0-preview.19073.11">
+      <Uri>https://github.com/dotnet/corefx</Uri>
+      <Sha>351ca391579740ae8af8a5405cffa16d152ad6b2</Sha>
+    </Dependency>
+    <Dependency Name="System.Text.Encodings.Web" Version="4.6.0-preview.19073.11">
+      <Uri>https://github.com/dotnet/corefx</Uri>
+      <Sha>351ca391579740ae8af8a5405cffa16d152ad6b2</Sha>
+    </Dependency>
+    <Dependency Name="Microsoft.Extensions.DependencyModel" Version="3.0.0-preview-27324-5">
+      <Uri>https://github.com/dotnet/core-setup</Uri>
+      <Sha>63a01b08e5d1d1a6b8544f598b3d3bda76e6e424</Sha>
+    </Dependency>
+    <Dependency Name="Microsoft.NETCore.App" Version="3.0.0-preview-27324-5">
+      <Uri>https://github.com/dotnet/core-setup</Uri>
+      <Sha>63a01b08e5d1d1a6b8544f598b3d3bda76e6e424</Sha>
+    </Dependency>
+  </ProductDependencies>
   <ToolsetDependencies>
+    <Dependency Name="Microsoft.AspNetCore.BenchmarkRunner.Sources" Version="3.0.0-preview.19074.2">
+      <Uri>https://github.com/aspnet/Extensions</Uri>
+      <Sha>0de62ae930da31048ba7e54c8cd0c6c0bcbd9095</Sha>
+    </Dependency>
+    <Dependency Name="Microsoft.AspNetCore.Testing" Version="3.0.0-preview.19074.2">
+      <Uri>https://github.com/aspnet/Extensions</Uri>
+      <Sha>0de62ae930da31048ba7e54c8cd0c6c0bcbd9095</Sha>
+    </Dependency>
     <Dependency Name="Microsoft.DotNet.Arcade.Sdk" Version="1.0.0-beta.19073.5">
       <Uri>https://github.com/dotnet/arcade</Uri>
       <Sha>af8ab7d7ca13d5f129c31cfa7aeda19f6d168e6e</Sha>

eng/Versions.props

@@ -46,23 +46,21 @@
   </PropertyGroup>
   <PropertyGroup Label="Package Versions">
     <BenchmarkDotNetPackageVersion>0.10.13</BenchmarkDotNetPackageVersion>
-    <MicrosoftAspNetCoreBenchmarkRunnerSourcesPackageVersion>3.0.0-preview-181106-14</MicrosoftAspNetCoreBenchmarkRunnerSourcesPackageVersion>
+    <MicrosoftAspNetCoreBenchmarkRunnerSourcesPackageVersion>3.0.0-preview.19074.2</MicrosoftAspNetCoreBenchmarkRunnerSourcesPackageVersion>
-    <MicrosoftAspNetCoreHtmlAbstractionsPackageVersion>3.0.0-alpha1-10717</MicrosoftAspNetCoreHtmlAbstractionsPackageVersion>
+    <MicrosoftAspNetCoreTestingPackageVersion>3.0.0-preview.19074.2</MicrosoftAspNetCoreTestingPackageVersion>
-    <MicrosoftAspNetCoreTestingPackageVersion>3.0.0-preview-181106-14</MicrosoftAspNetCoreTestingPackageVersion>
     <MicrosoftBuildFrameworkPackageVersion>15.8.166</MicrosoftBuildFrameworkPackageVersion>
     <MicrosoftBuildPackageVersion>15.8.166</MicrosoftBuildPackageVersion>
     <MicrosoftBuildUtilitiesCorePackageVersion>15.8.166</MicrosoftBuildUtilitiesCorePackageVersion>
     <MicrosoftCodeAnalysisCommonPackageVersion>2.11.0-beta1-final</MicrosoftCodeAnalysisCommonPackageVersion>
     <MicrosoftCodeAnalysisCSharpPackageVersion>2.11.0-beta1-final</MicrosoftCodeAnalysisCSharpPackageVersion>
     <MicrosoftCodeAnalysisWorkspacesCommonPackageVersion>2.11.0-beta1-final</MicrosoftCodeAnalysisWorkspacesCommonPackageVersion>
-    <MicrosoftExtensionsCommandLineUtilsSourcesPackageVersion>3.0.0-preview-181106-14</MicrosoftExtensionsCommandLineUtilsSourcesPackageVersion>
+    <MicrosoftExtensionsCommandLineUtilsSourcesPackageVersion>3.0.0-preview.19074.2</MicrosoftExtensionsCommandLineUtilsSourcesPackageVersion>
-    <MicrosoftExtensionsCopyOnWriteDictionarySourcesPackageVersion>3.0.0-preview-181106-14</MicrosoftExtensionsCopyOnWriteDictionarySourcesPackageVersion>
+    <MicrosoftExtensionsDependencyModelPackageVersion>3.0.0-preview-27324-5</MicrosoftExtensionsDependencyModelPackageVersion>
-    <MicrosoftExtensionsDependencyModelPackageVersion>3.0.0-preview-27113-06</MicrosoftExtensionsDependencyModelPackageVersion>
+    <MicrosoftExtensionsHashCodeCombinerSourcesPackageVersion>3.0.0-preview.19074.2</MicrosoftExtensionsHashCodeCombinerSourcesPackageVersion>
-    <MicrosoftExtensionsHashCodeCombinerSourcesPackageVersion>3.0.0-preview-181106-14</MicrosoftExtensionsHashCodeCombinerSourcesPackageVersion>
+    <MicrosoftExtensionsNonCapturingTimerSourcesPackageVersion>3.0.0-preview.19074.2</MicrosoftExtensionsNonCapturingTimerSourcesPackageVersion>
-    <MicrosoftExtensionsNonCapturingTimerSourcesPackageVersion>3.0.0-preview-181106-14</MicrosoftExtensionsNonCapturingTimerSourcesPackageVersion>
+    <MicrosoftNETCoreAppPackageVersion>3.0.0-preview-27324-5</MicrosoftNETCoreAppPackageVersion>
-    <MicrosoftExtensionsWebEncodersPackageVersion>3.0.0-alpha1-10717</MicrosoftExtensionsWebEncodersPackageVersion>
     <MicrosoftNETCoreApp21PackageVersion>2.1.3</MicrosoftNETCoreApp21PackageVersion>
-    <MicrosoftNETCoreApp30PackageVersion>3.0.0-preview-27113-06</MicrosoftNETCoreApp30PackageVersion>
+    <MicrosoftNETCoreApp30PackageVersion>$(MicrosoftNETCoreAppPackageVersion)</MicrosoftNETCoreApp30PackageVersion>
     <MicrosoftNETFrameworkReferenceAssemblies>1.0.0-alpha-004</MicrosoftNETFrameworkReferenceAssemblies>
     <MicrosoftNetRoslynDiagnosticsPackageVersion>2.6.2</MicrosoftNetRoslynDiagnosticsPackageVersion>
     <MicrosoftVisualStudioComponentModelHostPackageVersion>16.0.189-g83e7c53a57</MicrosoftVisualStudioComponentModelHostPackageVersion>
@@ -94,9 +92,8 @@
     <VSMAC_NewtonsoftJsonPackageVersion>10.0.3</VSMAC_NewtonsoftJsonPackageVersion>
     <TEST_NewtonsoftJsonPackageVersion>11.0.1</TEST_NewtonsoftJsonPackageVersion>
     <StreamJsonRpcPackageVersion>1.3.23</StreamJsonRpcPackageVersion>
-    <SystemDiagnosticsDiagnosticSourcePackageVersion>4.6.0-preview1-26907-04</SystemDiagnosticsDiagnosticSourcePackageVersion>
+    <SystemDiagnosticsDiagnosticSourcePackageVersion>4.6.0-preview.19073.11</SystemDiagnosticsDiagnosticSourcePackageVersion>
-    <SystemRuntimeInteropServicesRuntimeInformationPackageVersion>4.3.0</SystemRuntimeInteropServicesRuntimeInformationPackageVersion>
+    <SystemTextEncodingsWebPackageVersion>4.6.0-preview.19073.11</SystemTextEncodingsWebPackageVersion>
-    <SystemValueTuplePackageVersion>4.6.0-preview1-26829-04</SystemValueTuplePackageVersion>
     <VSIX_MicrosoftCodeAnalysisPackageVersion>3.0.0-beta2-18612-05</VSIX_MicrosoftCodeAnalysisPackageVersion>
     <VSIX_MicrosoftCodeAnalysisCommonPackageVersion>3.0.0-beta2-18612-05</VSIX_MicrosoftCodeAnalysisCommonPackageVersion>
     <VSIX_MicrosoftCodeAnalysisCSharpFeaturesPackageVersion>3.0.0-beta2-18612-05</VSIX_MicrosoftCodeAnalysisCSharpFeaturesPackageVersion>

src/Razor/src/Microsoft.VisualStudio.Mac.LanguageServices.Razor/Microsoft.VisualStudio.Mac.LanguageServices.Razor.csproj

@@ -12,7 +12,6 @@
   <ItemGroup>
     <PackageReference Include="MonoDevelop.Sdk" Version="$(MonoDevelopSdkPackageVersion)" />
     <PackageReference Include="Newtonsoft.Json" Version="$(VSMAC_NewtonsoftJsonPackageVersion)" />
-    <PackageReference Include="System.ValueTuple" Version="$(SystemValueTuplePackageVersion)" />
   </ItemGroup>
 
   <ItemGroup>

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib/Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.csproj

@@ -5,9 +5,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.AspNetCore.Html.Abstractions" Version="$(MicrosoftAspNetCoreHtmlAbstractionsPackageVersion)" />
     <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="$(SystemDiagnosticsDiagnosticSourcePackageVersion)" />
-
+    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWebPackageVersion)" />
+    
     <ProjectReference Include="..\Microsoft.AspNetCore.Razor.Test.ComponentShim\Microsoft.AspNetCore.Razor.Test.ComponentShim.csproj" />
   </ItemGroup>
 

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X/Microsoft.AspNetCore.Html/IHtmlContent.cs

@@ -0,0 +1,22 @@
+// 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.Text.Encodings.Web;
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// HTML content which can be written to a TextWriter.
+    /// </summary>
+    public interface IHtmlContent
+    {
+        /// <summary>
+        /// Writes the content by encoding it with the specified <paramref name="encoder"/>
+        /// to the specified <paramref name="writer"/>.
+        /// </summary>
+        /// <param name="writer">The <see cref="TextWriter"/> to which the content is written.</param>
+        /// <param name="encoder">The <see cref="HtmlEncoder"/> which encodes the content to be written.</param>
+        void WriteTo(TextWriter writer, HtmlEncoder encoder);
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X/Microsoft.AspNetCore.Html/IHtmlContentBuilder.cs

@@ -0,0 +1,40 @@
+// 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.
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// A builder for HTML content.
+    /// </summary>
+    public interface IHtmlContentBuilder : IHtmlContentContainer
+    {
+        /// <summary>
+        /// Appends an <see cref="IHtmlContent"/> instance.
+        /// </summary>
+        /// <param name="content">The <see cref="IHtmlContent"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder AppendHtml(IHtmlContent content);
+
+        /// <summary>
+        /// Appends a <see cref="string"/> value. The value is treated as unencoded as-provided, and will be HTML
+        /// encoded before writing to output.
+        /// </summary>
+        /// <param name="unencoded">The <see cref="string"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder Append(string unencoded);
+
+        /// <summary>
+        /// Appends an HTML encoded <see cref="string"/> value. The value is treated as HTML encoded as-provided, and
+        /// no further encoding will be performed.
+        /// </summary>
+        /// <param name="encoded">The HTML encoded <see cref="string"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder AppendHtml(string encoded);
+
+        /// <summary>
+        /// Clears the content.
+        /// </summary>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder Clear();
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X/Microsoft.AspNetCore.Html/IHtmlContentContainer.cs

@@ -0,0 +1,30 @@
+// 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.
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// Defines a contract for <see cref="IHtmlContent"/> instances made up of several components which
+    /// can be copied into an <see cref="IHtmlContentBuilder"/>.
+    /// </summary>
+    public interface IHtmlContentContainer : IHtmlContent
+    {
+        /// <summary>
+        /// Copies the contained content of this <see cref="IHtmlContentContainer"/> into <paramref name="builder"/>.
+        /// </summary>
+        /// <param name="builder">The <see cref="IHtmlContentBuilder"/>.</param>
+        void CopyTo(IHtmlContentBuilder builder);
+
+        /// <summary>
+        /// <para>
+        /// Moves the contained content of this <see cref="IHtmlContentContainer"/> into <paramref name="builder"/>.
+        /// </para>
+        /// <para>
+        /// After <see cref="MoveTo"/> is called, this <see cref="IHtmlContentContainer"/> instance should be left
+        /// in an empty state.
+        /// </para>
+        /// </summary>
+        /// <param name="builder">The <see cref="IHtmlContentBuilder"/>.</param>
+        void MoveTo(IHtmlContentBuilder builder);
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X/Microsoft.AspNetCore.Razor.TagHelpers/TagHelperContent.cs

@@ -30,7 +30,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetHtmlContent(IHtmlContent htmlContent)
         {
-            HtmlContentBuilderExtensions.SetHtmlContent(this, htmlContent);
             return this;
         }
 
@@ -44,7 +43,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetContent(string unencoded)
         {
-            HtmlContentBuilderExtensions.SetContent(this, unencoded);
             return this;
         }
 
@@ -58,7 +56,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetHtmlContent(string encoded)
         {
-            HtmlContentBuilderExtensions.SetHtmlContent(this, encoded);
             return this;
         }
 
@@ -96,7 +93,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the append operation has completed.</returns>
         public TagHelperContent AppendFormat(string format, params object[] args)
         {
-            HtmlContentBuilderExtensions.AppendFormat(this, null, format, args);
             return this;
         }
 
@@ -113,7 +109,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the append operation has completed.</returns>
         public TagHelperContent AppendFormat(IFormatProvider provider, string format, params object[] args)
         {
-            HtmlContentBuilderExtensions.AppendFormat(this, provider, format, args);
             return this;
         }
 

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X/Microsoft.AspNetCore.Razor.Test.MvcShim.Version1_X.csproj

@@ -6,8 +6,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.AspNetCore.Html.Abstractions" Version="$(MicrosoftAspNetCoreHtmlAbstractionsPackageVersion)" />
     <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="$(SystemDiagnosticsDiagnosticSourcePackageVersion)" />
+    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWebPackageVersion)" />
   </ItemGroup>
 
 </Project>

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version2_X/Microsoft.AspNetCore.Html/HtmlString.cs

@@ -0,0 +1,61 @@
+// 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.IO;
+using System.Text.Encodings.Web;
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// An <see cref="IHtmlContent"/> implementation that wraps an HTML encoded <see cref="string"/>.
+    /// </summary>
+    public class HtmlString : IHtmlContent
+    {
+        /// <summary>
+        /// An <see cref="HtmlString"/> instance for <see cref="Environment.NewLine"/>.
+        /// </summary>
+        public static readonly HtmlString NewLine = new HtmlString(Environment.NewLine);
+
+        /// <summary>
+        /// An <see cref="HtmlString"/> instance for <see cref="string.Empty"/>.
+        /// </summary>
+        public static readonly HtmlString Empty = new HtmlString(string.Empty);
+
+        /// <summary>
+        /// Creates a new <see cref="HtmlString"/>.
+        /// </summary>
+        /// <param name="value">The HTML encoded value.</param>
+        public HtmlString(string value)
+        {
+            Value = value;
+        }
+
+        /// <summary>
+        /// Gets the HTML encoded value.
+        /// </summary>
+        public string Value { get; }
+
+        /// <inheritdoc />
+        public void WriteTo(TextWriter writer, HtmlEncoder encoder)
+        {
+            if (writer == null)
+            {
+                throw new ArgumentNullException(nameof(writer));
+            }
+
+            if (encoder == null)
+            {
+                throw new ArgumentNullException(nameof(encoder));
+            }
+
+            writer.Write(Value);
+        }
+
+        /// <inheritdoc />
+        public override string ToString()
+        {
+            return Value ?? string.Empty;
+        }
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version2_X/Microsoft.AspNetCore.Html/IHtmlContent.cs

@@ -0,0 +1,22 @@
+// 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.Text.Encodings.Web;
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// HTML content which can be written to a TextWriter.
+    /// </summary>
+    public interface IHtmlContent
+    {
+        /// <summary>
+        /// Writes the content by encoding it with the specified <paramref name="encoder"/>
+        /// to the specified <paramref name="writer"/>.
+        /// </summary>
+        /// <param name="writer">The <see cref="TextWriter"/> to which the content is written.</param>
+        /// <param name="encoder">The <see cref="HtmlEncoder"/> which encodes the content to be written.</param>
+        void WriteTo(TextWriter writer, HtmlEncoder encoder);
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version2_X/Microsoft.AspNetCore.Html/IHtmlContentBuilder.cs

@@ -0,0 +1,40 @@
+// 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.
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// A builder for HTML content.
+    /// </summary>
+    public interface IHtmlContentBuilder : IHtmlContentContainer
+    {
+        /// <summary>
+        /// Appends an <see cref="IHtmlContent"/> instance.
+        /// </summary>
+        /// <param name="content">The <see cref="IHtmlContent"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder AppendHtml(IHtmlContent content);
+
+        /// <summary>
+        /// Appends a <see cref="string"/> value. The value is treated as unencoded as-provided, and will be HTML
+        /// encoded before writing to output.
+        /// </summary>
+        /// <param name="unencoded">The <see cref="string"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder Append(string unencoded);
+
+        /// <summary>
+        /// Appends an HTML encoded <see cref="string"/> value. The value is treated as HTML encoded as-provided, and
+        /// no further encoding will be performed.
+        /// </summary>
+        /// <param name="encoded">The HTML encoded <see cref="string"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder AppendHtml(string encoded);
+
+        /// <summary>
+        /// Clears the content.
+        /// </summary>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder Clear();
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version2_X/Microsoft.AspNetCore.Html/IHtmlContentContainer.cs

@@ -0,0 +1,30 @@
+// 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.
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// Defines a contract for <see cref="IHtmlContent"/> instances made up of several components which
+    /// can be copied into an <see cref="IHtmlContentBuilder"/>.
+    /// </summary>
+    public interface IHtmlContentContainer : IHtmlContent
+    {
+        /// <summary>
+        /// Copies the contained content of this <see cref="IHtmlContentContainer"/> into <paramref name="builder"/>.
+        /// </summary>
+        /// <param name="builder">The <see cref="IHtmlContentBuilder"/>.</param>
+        void CopyTo(IHtmlContentBuilder builder);
+
+        /// <summary>
+        /// <para>
+        /// Moves the contained content of this <see cref="IHtmlContentContainer"/> into <paramref name="builder"/>.
+        /// </para>
+        /// <para>
+        /// After <see cref="MoveTo"/> is called, this <see cref="IHtmlContentContainer"/> instance should be left
+        /// in an empty state.
+        /// </para>
+        /// </summary>
+        /// <param name="builder">The <see cref="IHtmlContentBuilder"/>.</param>
+        void MoveTo(IHtmlContentBuilder builder);
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version2_X/Microsoft.AspNetCore.Razor.TagHelpers/TagHelperContent.cs

@@ -30,7 +30,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetHtmlContent(IHtmlContent htmlContent)
         {
-            HtmlContentBuilderExtensions.SetHtmlContent(this, htmlContent);
             return this;
         }
 
@@ -44,7 +43,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetContent(string unencoded)
         {
-            HtmlContentBuilderExtensions.SetContent(this, unencoded);
             return this;
         }
 
@@ -58,7 +56,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetHtmlContent(string encoded)
         {
-            HtmlContentBuilderExtensions.SetHtmlContent(this, encoded);
             return this;
         }
 
@@ -96,7 +93,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the append operation has completed.</returns>
         public TagHelperContent AppendFormat(string format, params object[] args)
         {
-            HtmlContentBuilderExtensions.AppendFormat(this, null, format, args);
             return this;
         }
 
@@ -113,7 +109,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the append operation has completed.</returns>
         public TagHelperContent AppendFormat(IFormatProvider provider, string format, params object[] args)
         {
-            HtmlContentBuilderExtensions.AppendFormat(this, provider, format, args);
             return this;
         }
 

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim.Version2_X/Microsoft.AspNetCore.Razor.Test.MvcShim.Version2_X.csproj

@@ -6,8 +6,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.AspNetCore.Html.Abstractions" Version="$(MicrosoftAspNetCoreHtmlAbstractionsPackageVersion)" />
     <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="$(SystemDiagnosticsDiagnosticSourcePackageVersion)" />
+    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWebPackageVersion)" />
   </ItemGroup>
 
 </Project>

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim/Microsoft.AspNetCore.Html/HtmlString.cs

@@ -0,0 +1,61 @@
+// 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.IO;
+using System.Text.Encodings.Web;
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// An <see cref="IHtmlContent"/> implementation that wraps an HTML encoded <see cref="string"/>.
+    /// </summary>
+    public class HtmlString : IHtmlContent
+    {
+        /// <summary>
+        /// An <see cref="HtmlString"/> instance for <see cref="Environment.NewLine"/>.
+        /// </summary>
+        public static readonly HtmlString NewLine = new HtmlString(Environment.NewLine);
+
+        /// <summary>
+        /// An <see cref="HtmlString"/> instance for <see cref="string.Empty"/>.
+        /// </summary>
+        public static readonly HtmlString Empty = new HtmlString(string.Empty);
+
+        /// <summary>
+        /// Creates a new <see cref="HtmlString"/>.
+        /// </summary>
+        /// <param name="value">The HTML encoded value.</param>
+        public HtmlString(string value)
+        {
+            Value = value;
+        }
+
+        /// <summary>
+        /// Gets the HTML encoded value.
+        /// </summary>
+        public string Value { get; }
+
+        /// <inheritdoc />
+        public void WriteTo(TextWriter writer, HtmlEncoder encoder)
+        {
+            if (writer == null)
+            {
+                throw new ArgumentNullException(nameof(writer));
+            }
+
+            if (encoder == null)
+            {
+                throw new ArgumentNullException(nameof(encoder));
+            }
+
+            writer.Write(Value);
+        }
+
+        /// <inheritdoc />
+        public override string ToString()
+        {
+            return Value ?? string.Empty;
+        }
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim/Microsoft.AspNetCore.Html/IHtmlContent.cs

@@ -0,0 +1,22 @@
+// 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.Text.Encodings.Web;
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// HTML content which can be written to a TextWriter.
+    /// </summary>
+    public interface IHtmlContent
+    {
+        /// <summary>
+        /// Writes the content by encoding it with the specified <paramref name="encoder"/>
+        /// to the specified <paramref name="writer"/>.
+        /// </summary>
+        /// <param name="writer">The <see cref="TextWriter"/> to which the content is written.</param>
+        /// <param name="encoder">The <see cref="HtmlEncoder"/> which encodes the content to be written.</param>
+        void WriteTo(TextWriter writer, HtmlEncoder encoder);
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim/Microsoft.AspNetCore.Html/IHtmlContentBuilder.cs

@@ -0,0 +1,40 @@
+// 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.
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// A builder for HTML content.
+    /// </summary>
+    public interface IHtmlContentBuilder : IHtmlContentContainer
+    {
+        /// <summary>
+        /// Appends an <see cref="IHtmlContent"/> instance.
+        /// </summary>
+        /// <param name="content">The <see cref="IHtmlContent"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder AppendHtml(IHtmlContent content);
+
+        /// <summary>
+        /// Appends a <see cref="string"/> value. The value is treated as unencoded as-provided, and will be HTML
+        /// encoded before writing to output.
+        /// </summary>
+        /// <param name="unencoded">The <see cref="string"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder Append(string unencoded);
+
+        /// <summary>
+        /// Appends an HTML encoded <see cref="string"/> value. The value is treated as HTML encoded as-provided, and
+        /// no further encoding will be performed.
+        /// </summary>
+        /// <param name="encoded">The HTML encoded <see cref="string"/> to append.</param>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder AppendHtml(string encoded);
+
+        /// <summary>
+        /// Clears the content.
+        /// </summary>
+        /// <returns>The <see cref="IHtmlContentBuilder"/>.</returns>
+        IHtmlContentBuilder Clear();
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim/Microsoft.AspNetCore.Html/IHtmlContentContainer.cs

@@ -0,0 +1,30 @@
+// 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.
+
+namespace Microsoft.AspNetCore.Html
+{
+    /// <summary>
+    /// Defines a contract for <see cref="IHtmlContent"/> instances made up of several components which
+    /// can be copied into an <see cref="IHtmlContentBuilder"/>.
+    /// </summary>
+    public interface IHtmlContentContainer : IHtmlContent
+    {
+        /// <summary>
+        /// Copies the contained content of this <see cref="IHtmlContentContainer"/> into <paramref name="builder"/>.
+        /// </summary>
+        /// <param name="builder">The <see cref="IHtmlContentBuilder"/>.</param>
+        void CopyTo(IHtmlContentBuilder builder);
+
+        /// <summary>
+        /// <para>
+        /// Moves the contained content of this <see cref="IHtmlContentContainer"/> into <paramref name="builder"/>.
+        /// </para>
+        /// <para>
+        /// After <see cref="MoveTo"/> is called, this <see cref="IHtmlContentContainer"/> instance should be left
+        /// in an empty state.
+        /// </para>
+        /// </summary>
+        /// <param name="builder">The <see cref="IHtmlContentBuilder"/>.</param>
+        void MoveTo(IHtmlContentBuilder builder);
+    }
+}

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim/Microsoft.AspNetCore.Razor.TagHelpers/TagHelperContent.cs

@@ -30,7 +30,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetHtmlContent(IHtmlContent htmlContent)
         {
-            HtmlContentBuilderExtensions.SetHtmlContent(this, htmlContent);
             return this;
         }
 
@@ -44,7 +43,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetContent(string unencoded)
         {
-            HtmlContentBuilderExtensions.SetContent(this, unencoded);
             return this;
         }
 
@@ -58,7 +56,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the set operation has completed.</returns>
         public TagHelperContent SetHtmlContent(string encoded)
         {
-            HtmlContentBuilderExtensions.SetHtmlContent(this, encoded);
             return this;
         }
 
@@ -96,7 +93,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the append operation has completed.</returns>
         public TagHelperContent AppendFormat(string format, params object[] args)
         {
-            HtmlContentBuilderExtensions.AppendFormat(this, null, format, args);
             return this;
         }
 
@@ -113,7 +109,6 @@ namespace Microsoft.AspNetCore.Razor.TagHelpers
         /// <returns>A reference to this instance after the append operation has completed.</returns>
         public TagHelperContent AppendFormat(IFormatProvider provider, string format, params object[] args)
         {
-            HtmlContentBuilderExtensions.AppendFormat(this, provider, format, args);
             return this;
         }
 

src/Razor/test/Microsoft.AspNetCore.Razor.Test.MvcShim/Microsoft.AspNetCore.Razor.Test.MvcShim.csproj

@@ -6,9 +6,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.AspNetCore.Html.Abstractions" Version="$(MicrosoftAspNetCoreHtmlAbstractionsPackageVersion)" />
     <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="$(SystemDiagnosticsDiagnosticSourcePackageVersion)" />
-
+    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWebPackageVersion)" />
+    
     <ProjectReference Include="..\Microsoft.AspNetCore.Razor.Test.ComponentShim\Microsoft.AspNetCore.Razor.Test.ComponentShim.csproj" />
   </ItemGroup>
 

src/Razor/test/Microsoft.NET.Sdk.Razor.Test/IntegrationTests/BuildIntegrationTest.cs

@@ -245,12 +245,13 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileExists(result, OutputPath, "SimpleMvc.deps.json");
             var depsFilePath = Path.Combine(Project.DirectoryPath, OutputPath, "SimpleMvc.deps.json");
             var dependencyContext = ReadDependencyContext(depsFilePath);
+
             // Pick a couple of libraries and ensure they have some compile references
-            var packageReference = dependencyContext.CompileLibraries.First(l => l.Name == "Microsoft.AspNetCore.Html.Abstractions");
+            var packageReference = dependencyContext.CompileLibraries.First(l => l.Name == "Microsoft.NETCore.App");
             Assert.NotEmpty(packageReference.Assemblies);
 
             var projectReference = dependencyContext.CompileLibraries.First(l => l.Name == "SimpleMvc");
-            Assert.NotEmpty(packageReference.Assemblies);
+            Assert.NotEmpty(projectReference.Assemblies);
 
             Assert.Contains(customDefine, dependencyContext.CompilationOptions.Defines);
         }

src/Razor/test/Microsoft.NET.Sdk.Razor.Test/Microsoft.NET.Sdk.Razor.Test.csproj

@@ -29,7 +29,6 @@
   <!-- The test projects rely on these binaries being available -->
   <ItemGroup>
     <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="$(SystemDiagnosticsDiagnosticSourcePackageVersion)" />
-    <PackageReference Include="Microsoft.AspNetCore.Html.Abstractions" Version="$(MicrosoftAspNetCoreHtmlAbstractionsPackageVersion)" />
   </ItemGroup>
 
   <ItemGroup>

src/Razor/test/testapps/AppWithP2PReference/AppWithP2PReference.csproj

@@ -27,7 +27,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>

src/Razor/test/testapps/ClassLibrary/ClassLibrary.csproj

@@ -30,7 +30,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>

src/Razor/test/testapps/ClassLibrary2/ClassLibrary2.csproj

@@ -27,7 +27,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>

src/Razor/test/testapps/LargeProject/LargeProject.csproj

@@ -24,7 +24,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>  

src/Razor/test/testapps/MvcWithComponents/MvcWithComponents.csproj

@@ -25,7 +25,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>

src/Razor/test/testapps/SimpleMvc/SimpleMvc.csproj

@@ -24,7 +24,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>

src/Razor/test/testapps/SimpleMvcFSharp/SimpleMvcFSharp.fsproj

@@ -29,7 +29,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>  

src/Razor/test/testapps/SimplePages/SimplePages.csproj

@@ -24,7 +24,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(BinariesRoot)'!=''">
-    <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Html.Abstractions.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.ComponentShim.dll"/>
     <Reference Include="$(BinariesRoot)\Microsoft.AspNetCore.Razor.Test.MvcShim.ClassLib.dll"/>
   </ItemGroup>