Refactor projection writer: cleanup passes, parallelization, and CI-driven correctness fixes

nuget/Microsoft.Windows.CsWinRT.CsWinRTGen.targets

@@ -349,6 +349,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
       AdditionalArguments="@(CsWinRTGeneratorAdditionalArgument)"
       StandardOutputImportance="$(CsWinRTGeneratorStandardOutputImportance)"
       StandardErrorImportance="$(CsWinRTGeneratorStandardErrorImportance)"
+      MaxDegreesOfParallelism="$(CsWinRTGeneratorMaxDegreesOfParallelism)"
       LogStandardErrorAsError="$(CsWinRTGeneratorLogStandardErrorAsError)" />
 
     <!-- Set the metadata for the interop .dll item and add it to the required output groups -->
@@ -411,6 +412,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
       CsWinRTToolsArchitecture="$(CsWinRTToolsArchitecture)"
       StandardOutputImportance="$(CsWinRTGeneratorStandardOutputImportance)"
       StandardErrorImportance="$(CsWinRTGeneratorStandardErrorImportance)"
+      MaxDegreesOfParallelism="$(CsWinRTGeneratorMaxDegreesOfParallelism)"
       LogStandardErrorAsError="$(CsWinRTGeneratorLogStandardErrorAsError)" />
 
     <!-- Only wire up the component DLL if it was actually produced (i.e. component types were found) -->
@@ -488,6 +490,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
       AdditionalArguments="@(CsWinRTGeneratorAdditionalArgument)"
       StandardOutputImportance="$(CsWinRTGeneratorStandardOutputImportance)"
       StandardErrorImportance="$(CsWinRTGeneratorStandardErrorImportance)"
+      MaxDegreesOfParallelism="$(CsWinRTGeneratorMaxDegreesOfParallelism)"
       LogStandardErrorAsError="$(CsWinRTGeneratorLogStandardErrorAsError)" />
 
     <!-- Set the metadata for the SDK projection .dll item -->
@@ -573,6 +576,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
       AdditionalArguments="@(CsWinRTGeneratorAdditionalArgument)"
       StandardOutputImportance="$(CsWinRTGeneratorStandardOutputImportance)"
       StandardErrorImportance="$(CsWinRTGeneratorStandardErrorImportance)"
+      MaxDegreesOfParallelism="$(CsWinRTGeneratorMaxDegreesOfParallelism)"
       LogStandardErrorAsError="$(CsWinRTGeneratorLogStandardErrorAsError)" />
 
     <!-- Set the metadata for the SDK XAML .dll item -->

src/Tests/CSWinMDComponent/CSWinMDComponent.vcxproj.filters

@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <Filter Include="Resources">
+      <UniqueIdentifier>accd3aa8-1ba0-4223-9bbe-0c431709210b</UniqueIdentifier>
+      <Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tga;tiff;tif;png;wav;mfcribbon-ms</Extensions>
+    </Filter>
+    <Filter Include="Generated Files">
+      <UniqueIdentifier>{926ab91d-31b4-48c3-b9a4-e681349f27f0}</UniqueIdentifier>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="pch.cpp" />
+    <ClCompile Include="$(GeneratedFilesDir)module.g.cpp" />
+    <ClCompile Include="Class1.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="pch.h" />
+    <ClInclude Include="Class1.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="CSWinMDComponent.def" />
+    <None Include="CSWinMDComponent.cs" />
+    <None Include="packages.config" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="PropertySheet.props" />
+  </ItemGroup>
+  <ItemGroup>
+    <Text Include="readme.txt" />
+  </ItemGroup>
+</Project>

src/WinRT.Generator.Tasks/RunCsWinRTMergedProjectionGenerator.cs

@@ -86,6 +86,12 @@ public sealed class RunCsWinRTMergedProjectionGenerator : ToolTask
     /// </summary>
     public bool WindowsUIXamlProjection { get; set; }
 
+    /// <summary>
+    /// Gets or sets the maximum number of parallel tasks the projection writer is allowed to dispatch.
+    /// </summary>
+    /// <remarks>If not set, the default will match the number of available processor cores.</remarks>
+    public int MaxDegreesOfParallelism { get; set; } = -1;
+
     /// <inheritdoc/>
     protected override string ToolName => "cswinrtprojectiongen.exe";
 
@@ -208,6 +214,8 @@ protected override string GenerateResponseFileCommands()
             AppendResponseFileCommand(args, "--windows-ui-xaml-projection", "true");
         }
 
+        AppendResponseFileCommand(args, "--max-degrees-of-parallelism", MaxDegreesOfParallelism.ToString());
+
         // Add any additional arguments that are not statically known
         foreach (ITaskItem additionalArgument in AdditionalArguments ?? [])
         {

src/WinRT.Interop.Generator/Errors/WellKnownInteropException.cs

@@ -10,7 +10,7 @@
 namespace WindowsRuntime.InteropGenerator.Errors;
 
 /// <summary>
-/// A well known exception for the interop generator.
+/// A well-known exception for the interop generator.
 /// </summary>
 internal sealed class WellKnownInteropException : Exception
 {

src/WinRT.Interop.Generator/Errors/WellKnownInteropWarning.cs

@@ -8,7 +8,7 @@
 namespace WindowsRuntime.InteropGenerator.Errors;
 
 /// <summary>
-/// A well known warning for the interop generator.
+/// A well-known warning for the interop generator.
 /// </summary>
 internal sealed class WellKnownInteropWarning
 {