Embedded nuget work and sample

docs/embedded.md

@@ -0,0 +1,103 @@
+# Embedded C#/WinRT Support
+
+## Overview
+
+**Note**: Embedded support is currently **in preview**. 
+
+Embedded support is a C#/WinRT feature that allows you to compile the c# projection for the component, within the library/app itself. 
+
+This is done by setting the build property `CsWinRTEmbedded` to `true` in the app or library's project file. 
+
+Enabling embedded support compiles the sources for WinRT.Runtime with the project.
+For any types from the component which you want to embed in your project, they must be specified using `CsWinRTIncludes`.
+The specified types will be projected and embedded into the project's *.dll*. 
+This means projects using embedded support no longer have a dependency on a projection for the component, `WinRT.Runtime.dll` or `Microsoft.Windows.SDK.NET.dll` in the case of the Windows SDK projection.
+
+For an example, you can look at the [sample](https://github.com/microsoft/CsWinRT/tree/master/src/Samples/TestEmbedded). 
+
+Embedded support introduces new features to the C#/WinRT toolchain:
+ * Decreased component/app size: The developer only needs to include the minimum necessary parts of the Windows SDK required by their component or app, reducing the size of the output .dll significantly.
+ * Downlevel support: App developers on .NET 5+ can target Windows 7 (`net5.0-windows`) and light-up on Windows 10 
+  (and Windows 11) when consuming an embedded .NET 5+ library. 
+ * Removes the need for multi-targeting: Library authors can support all .NET Standard 2.0 app consumers, including .NET 5+, without the need for multi-targeting. App consumers are able to target any .NET Standard 2.0 compatible TFM (e.g. `netcoreapp3.1`, `net48`, and `net5.0-windows`).
+
+It is important to remember that embedded support constrains the scope of Windows Runtime types to your binary. 
+
+## Scenarios
+
+This feature allows C# apps and libraries to target `net5.0` (and above), .NET Framework 4.6.1+, `netcoreapp3.1`, and `netstandard2.0` while also using the Windows SDK.
+Moreover, a library can target `netstandard2.0` and be able to run on NetFX, Net Core and Net 5. 
+
+Note: the `netstandard2.0` generated projection is not optimized for .NET 5 and won't be as performant. 
+
+## Usage 
+
+Using embedded support allows you to target non-Windows specific TFMs and older versions of .NET. 
+You will need to set a few properties:
+  * `CsWinRTEmbedded` - must be set to `true` to include the sources
+  * `CsWinRTIncludes` - Specify the types to be projected; error `CS0246` will highlight any missing namespaces
+  * `CsWinRTWindowsMetadata` - must be set to the Windows SDK release to use for Windows APIs
+  * `LangVersion` - must be set to `9` because the CsWinRT generated sources use C# 9
+
+Targeting `netstandard2.0` requires adding the following two package references:
+
+```xml
+<PackageReference Include="System.Memory" Version="4.5.4" />
+<PackageReference Include="System.Runtime.Extensions" Version="4.3.1" />
+```
+
+Here is an example project file for a library cross-targeting and embedding a C#/WinRT generated projection.
+
+```csproj
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>net6.0-windows;net5.0-windows;netstandard2.0</TargetFrameworks>
+    <Platforms>x64;x86</Platforms>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <LangVersion>9</LangVersion>
+    <CsWinRTEmbedded>true</CsWinRTEmbedded>
+    <CsWinRTWindowsMetadata>10.0.19041.0</CsWinRTWindowsMetadata>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Windows.CsWinRT" Version="$(CsWinRTVersion)" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\path\CppwinrtComponent\CppwinrtComponent.vcxproj" />
+  </ItemGroup> 
+
+  <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
+    <PackageReference Include="System.Memory" Version="4.5.4" />
+    <PackageReference Include="System.Runtime.Extensions" Version="4.3.1" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <CsWinRTIncludes>
+      CppwinrtComponent;
+      Windows.Devices.Geolocation;
+      Windows.Foundation;
+    </CsWinRTIncludes>
+  </PropertyGroup>
+
+</Project>
+```
+
+You will need to enable Windows Desktop Compatible for all your referenced C++/WinRT components -- either via the properties or in the `.vcxproj` file.
+
+If you try to use an embedded projection of a native (C++/WinRT) component, via ProjectReference, then you may encounter a runtime error `CLASS_NOT_REGISTERED`.
+You can fix this by unloading the native component project in Visual Studio, and adding the following:
+
+```vcxproj
+  <PropertyGroup Label="Configuration">
+    <DesktopCompatible>true</DesktopCompatible>
+  </PropertyGroup>
+```
+
+Alternatively, you can right-click the C++ project in Visual Studio, select Properties > General > Project Defaults,
+ and set Windows Desktop Compatible to Yes for all configurations/platforms.
+
+If you find any other issues using embedded support, please [file an issue]()!

nuget/Microsoft.Windows.CsWinRT.Embedded.targets

@@ -0,0 +1,75 @@
+<!--
+***********************************************************************************************
+Copyright (C) Microsoft Corporation. All rights reserved.
+***********************************************************************************************
+-->
+<Project ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003"> 
+
+  <PropertyGroup> 
+
+<!-- Activate the internal version of the runtime layer --> 
+    <DefineConstants>$(DefineConstants);EMBED</DefineConstants>
+<!-- Path to runtime sources, must update if their location changes in the .nuspec --> 
+    <CsWinRTEmbeddedTFMNet5OrGreater Condition="$([MSBuild]::GetTargetFrameworkVersion('$(TargetFramework)')) >= 5">true</CsWinRTEmbeddedTFMNet5OrGreater>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <CsWinRTEmbeddedSourcesAny Include="$(CsWinRTPath)embedded\any\*.cs"/>
+    <CsWinRTEmbeddedSourcesNet5 Include="$(CsWinRTPath)embedded\net5.0\*.cs"/>
+    <CsWinRTEmbeddedSourcesNet2 Include="$(CsWinRTPath)embedded\netstandard2.0\*.cs"/>
+  </ItemGroup>
+
+<!-- Copy sources that are for any framework -->
+  <Target Name="CsWinRTAddEmbeddedRuntime_AnySources"
+	    AfterTargets="CsWinRTGenerateProjection"
+	    BeforeTargets="CsWinRTIncludeProjection">
+
+    <Copy SourceFiles="@(CsWinRTEmbeddedSourcesAny)"
+          DestinationFolder="$(CsWinRTGeneratedFilesDir)"
+          UseHardlinksIfPossible="false"
+          SkipUnchangedFiles="true"/>
+
+  </Target>
+
+<!-- Copy netstandard2.0 sources -->
+  <Target Name="CsWinRTAddEmbeddedRuntime_Net2Sources"
+          Condition="'$(CsWinRTEmbeddedTFMNet5OrGreater)' != 'true'"
+          AfterTargets="CsWinRTGenerateProjection"
+          BeforeTargets="CsWinRTIncludeProjection">
+
+    <Copy SourceFiles="@(CsWinRTEmbeddedSourcesNet2)"
+          DestinationFolder="$(CsWinRTGeneratedFilesDir)"
+          UseHardlinksIfPossible="false"
+          SkipUnchangedFiles="true"/>
+
+  </Target>
+
+<!-- Copy net5.0 sources -->
+  <Target Name="CsWinRTAddEmbeddedRuntime_Net5Sources"
+          Condition="'$(CsWinRTEmbeddedTFMNet5OrGreater)' == 'true'"
+          AfterTargets="CsWinRTGenerateProjection"
+          BeforeTargets="CsWinRTIncludeProjection">
+
+    <Copy SourceFiles="@(CsWinRTEmbeddedSourcesNet5)"
+          DestinationFolder="$(CsWinRTGeneratedFilesDir)"
+          UseHardlinksIfPossible="false"
+          SkipUnchangedFiles="true"/>
+
+  </Target>
+
+
+<!-- Prevent collisions of WinRT.Runtime types -->  
+  <Target Name="RemoveWinRTRuntimeReference" 
+          Inputs="@(RuntimeCopyLocalItems)" 
+          AfterTargets="ResolvePackageAssets" 
+          Outputs="@(RuntimeCopyLocalItems)">
+
+    <ItemGroup>
+      <Reference Remove="WinRT.Runtime" /> 
+      <RuntimeCopyLocalItems Remove="@(RuntimeCopyLocalItems)" Condition="'%(DestinationSubPath)' == 'WinRT.Runtime.dll'"/>
+      <ResolvedCompileFileDefinitions Remove="@(ResolvedCompileFileDefinitions)" Condition="'%(HintPath)' == '$(CsWinRTPath)lib\net5.0\WinRT.Runtime.dll'"/>
+    </ItemGroup>
+
+  </Target>
+
+</Project>

nuget/Microsoft.Windows.CsWinRT.nuspec

@@ -24,6 +24,7 @@
     <file src="Microsoft.Windows.CsWinRT.props" target="build"/>
     <file src="Microsoft.Windows.CsWinRT.targets" target="build"/>
     <file src="Microsoft.Windows.CsWinRT.Authoring.targets" target="build"/>
+    <file src="Microsoft.Windows.CsWinRT.Embedded.targets" target="build"/>
     <file src="Microsoft.Windows.CsWinRT.IIDOptimizer.targets" target="build"/>
     <file src="Microsoft.Windows.CsWinRT.Prerelease*.targets" target="build"/>
     <file src="Microsoft.Windows.CsWinRT.Authoring.Transitive.targets" target="build"/>
@@ -36,6 +37,21 @@
     <file src="$winrt_host_arm$" target ="runtimes\win-arm\native"/>
     <file src="$winrt_host_arm64$" target ="runtimes\win-arm64\native"/>
     <file src="$winrt_shim$" target ="lib\net5.0\"/>
+
+    <!-- Add the WinRT.Runtime sources to the pkg for embedded scenarios -->
+
+    <file src="..\src\WinRT.Runtime\*.cs" exclude="..\src\WinRT.Runtime\*.net*.cs" target="embedded\any\" />
+    <file src="..\src\WinRT.Runtime\*net5*.cs" target="embedded\net5.0\" />
+    <file src="..\src\WinRT.Runtime\*netstandard2.0*.cs" target="embedded\netstandard2.0\" />
+
+    <file src="..\src\WinRT.Runtime\Interop\*.cs" exclude="..\src\WinRT.Runtime\Interop\*.net*.cs"  target="embedded\any\" />
+    <file src="..\src\WinRT.Runtime\Interop\*net5*.cs" target="embedded\net5.0\" />
+    <file src="..\src\WinRT.Runtime\Interop\*netstandard2.0*.cs" target="embedded\netstandard2.0\" />
+
+    <file src="..\src\WinRT.Runtime\Projections\*.cs" exclude="..\src\WinRT.Runtime\Projections\*.net*.cs" target="embedded\any\" />
+    <file src="..\src\WinRT.Runtime\Projections\*net5*.cs" target="embedded\net5.0\" />
+    <file src="..\src\WinRT.Runtime\Projections\*netstandard2.0*.cs" target="embedded\netstandard2.0\" />
+
     <file src="$guid_patch$" target ="build\tools\IIDOptimizer"/>
   </files>
 </package>

nuget/Microsoft.Windows.CsWinRT.targets

@@ -18,6 +18,8 @@ Copyright (C) Microsoft Corporation. All rights reserved.
     <TrackFileAccess Condition="'$(CsWinRTComponent)' != 'true'">false</TrackFileAccess> 
   </PropertyGroup>
 
+  <Import Project="$(MSBuildThisFileDirectory)Microsoft.Windows.CsWinRT.Embedded.targets" Condition="'$(CsWinRTEmbedded)' == 'true'"/>
+
   <!-- Remove WinRT.Host.dll and WinRT.Host.Shim.dll references -->
   <Target Name="CsWinRTRemoveHostingDllReferences" AfterTargets="ResolvePackageAssets" BeforeTargets="ResolveLockFileAnalyzers" Outputs="@(Reference)">
     <PropertyGroup>
@@ -99,14 +101,18 @@ Copyright (C) Microsoft Corporation. All rights reserved.
 -input $(CsWinRTInteropMetadata)
 -include WinRT.Interop
       </CsWinRTIncludeWinRTInterop>
+      <CsWinRTEmbeddedParam Condition="'$(CsWinRTEmbedded)' == 'true'">-embedded</CsWinRTEmbeddedParam>
+      <CsWinRTExeTFM Condition="$([MSBuild]::GetTargetFrameworkVersion('$(TargetFramework)')) >= 5">$(TargetFramework)</CsWinRTExeTFM>
+      <CsWinRTExeTFM Condition="'$(CsWinRTExeTFM)' == ''">netstandard2.0</CsWinRTExeTFM>
       <CsWinRTParams Condition="'$(CsWinRTParams)' == ''">
 $(CsWinRTCommandVerbosity)
--target $(TargetFramework)
+-target $(CsWinRTExeTFM)
 $(CsWinRTWindowsMetadataInput)
 -input @(CsWinRTInputs->'"%(FullPath)"', ' ')
 -output "$(CsWinRTGeneratedFilesDir.TrimEnd('\'))"
 $(CsWinRTFilters)
 $(CsWinRTIncludeWinRTInterop)
+$(CsWinRTEmbeddedParam)
       </CsWinRTParams>
     </PropertyGroup>
     <MakeDir Directories="$(CsWinRTGeneratedFilesDir)" />
@@ -131,7 +137,7 @@ $(CsWinRTIncludeWinRTInterop)
       <Compile Include="$(CsWinRTGeneratedFilesDir)*.cs" Exclude="@(Compile)" />
     </ItemGroup>
   </Target>
-  
+
   <Import Project="$(MSBuildThisFileDirectory)Microsoft.Windows.CsWinRT.Prerelease.targets" Condition="Exists('$(MSBuildThisFileDirectory)Microsoft.Windows.CsWinRT.Prerelease.targets')"/>
   <Import Project="$(MSBuildThisFileDirectory)Microsoft.Windows.CsWinRT.Authoring.targets" Condition="'$(CsWinRTComponent)' == 'true'"/>
   <Import Project="$(MSBuildThisFileDirectory)Microsoft.Windows.CsWinRT.IIDOptimizer.targets" Condition="'$(CsWinRTIIDOptimizerOptOut)' != 'true'"/>

src/Samples/TestEmbedded/C++ Components/Alpha/Alpha.cpp

@@ -0,0 +1,7 @@
+#include "pch.h"
+#include "Alpha.h"
+#include "Class.g.cpp"
+
+namespace winrt::Alpha::implementation
+{
+}

src/Samples/TestEmbedded/C++ Components/Alpha/Alpha.def

@@ -0,0 +1,3 @@
+EXPORTS
+DllCanUnloadNow = WINRT_CanUnloadNow                    PRIVATE
+DllGetActivationFactory = WINRT_GetActivationFactory    PRIVATE

src/Samples/TestEmbedded/C++ Components/Alpha/Alpha.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "Class.g.h"
+
+namespace winrt::Alpha::implementation
+{
+    struct Class : ClassT<Class>
+    {
+        Class() = default;
+    };
+}
+
+namespace winrt::Alpha::factory_implementation
+{
+    struct Class : ClassT<Class, implementation::Class>
+    {
+    };
+}

src/Samples/TestEmbedded/C++ Components/Alpha/Alpha.idl

@@ -0,0 +1,13 @@
+namespace Alpha
+{
+    [default_interface]
+    runtimeclass Class
+    {
+        Class();
+    }
+
+    interface IAlpha
+    {
+        Int32 Five();
+    }
+}