Use reflection or a compile-time only shim assembly to reference unexposed corelib types.

docs/workflow/testing/coreclr/test-configuration.md

@@ -52,8 +52,6 @@ Therefore the managed portion of each test **must not contain**:
 * Exclude test from JIT stress runs runs by adding the following to the csproj:
     * `<JitOptimizationSensitive>true</JitOptimizationSensitive>`
 * Add NuGet references by updating the following [test project](https://github.com/dotnet/runtime/blob/main/src/tests/Common/test_dependencies/test_dependencies.csproj).
-* Get access to System.Private.CoreLib types and methods that are not exposed via public surface by adding the following to the csproj:
-    * `<ReferenceSystemPrivateCoreLib>true</ReferenceSystemPrivateCoreLib>`
 * Any System.Private.CoreLib types and methods used by tests must be available for building on all platforms.
 This means there must be enough implementation for the C# compiler to find the referenced types and methods. Unsupported target platforms
 should simply `throw new PlatformNotSupportedException()` in its dummy method implementations.

src/coreclr/System.Private.CoreLib/src/Internal/Runtime/InteropServices/ComActivationContextInternal.cs

@@ -35,6 +35,7 @@ public partial struct ComActivationContext
     }
 
     [ComImport]
+    [TypeIdentifier]
     [ComVisible(false)]
     [Guid("00000001-0000-0000-C000-000000000046")]
     [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]

src/tests/Common/XUnitWrapperGenerator/XUnitWrapperGenerator.props

@@ -6,7 +6,6 @@
     <CompilerVisibleProperty Include="TargetArchitecture" />
     <CompilerVisibleProperty Include="Priority" />
     <!-- Properties that influence test harness generation -->
-    <CompilerVisibleProperty Include="ReferenceSystemPrivateCoreLib" />
     <CompilerVisibleProperty Include="IsMergedTestRunnerAssembly" />
     <CompilerVisibleProperty Include="TestFilter" />
     <CompilerVisibleItemMetadata Include="AdditionalFiles" MetadataName="IsOutOfProcessTestAssembly" />

src/tests/Directory.Build.targets

@@ -80,7 +80,6 @@
     <_WillCLRTestProjectBuild Condition="'$(BuildAllProjects)' != 'true'">true</_WillCLRTestProjectBuild>
     <_WillCLRTestProjectBuild Condition="'$(BuildAllProjects)' == 'true' And '$(CLRTestPriority)' &lt;= '$(CLRTestPriorityToBuild)'">true</_WillCLRTestProjectBuild>
     <_WillCLRTestProjectBuild Condition="'$(CLRTestBuildAllTargets)' != 'allTargets' And '$(CLRTestTargetUnsupported)' == 'true'">false</_WillCLRTestProjectBuild>
-    <_WillCLRTestProjectBuild Condition="'$(ReferenceSystemPrivateCoreLib)' == 'true' and '$(RuntimeFlavor)' == 'mono'">false</_WillCLRTestProjectBuild>
     <_WillCLRTestProjectBuild Condition="'$(DisableProjectBuild)' == 'true'">false</_WillCLRTestProjectBuild>
   </PropertyGroup>
   <PropertyGroup>
@@ -95,8 +94,6 @@
   <!-- RunOnly projects have a special build for dependent projects -->
   <Import Project="$(MSBuildThisFileDirectory)Common\runonly.targets" Condition="'$(CLRTestKind)' == 'RunOnly'" />
 
-  <Import Project="$(MSBuildThisFileDirectory)Common\override.targets" />
-
   <!-- We enable auto-unification of assembly references after importing the common targets.  Binding redirects are not needed
        for coreclr since it auto-unifies, so the warnings we get without this setting are just noise -->
   <PropertyGroup>
@@ -225,12 +222,11 @@
           BeforeTargets="BeforeResolveReferences"
   >
    <MSBuild Projects="$(MSBuildProjectFullPath)"
-            Targets="GetLiveRefAssemblies"
-            Condition="'$(ReferenceSystemPrivateCoreLib)' != 'true'">
+            Targets="GetLiveRefAssemblies">
     <Output TaskParameter="TargetOutputs" ItemName="Reference" />
    </MSBuild>
 
-    <ItemGroup Condition="'$(ReferenceSystemPrivateCoreLib)' != 'true'">
+    <ItemGroup >
       <Reference Include="$(TargetingPackPath)/*.dll" >
         <Private>false</Private>
       </Reference>
@@ -255,10 +251,6 @@
     <ProjectAssetsFile>$(BaseOutputPath)\packages\Common\test_dependencies\test_dependencies\project.assets.json</ProjectAssetsFile>
   </PropertyGroup>
 
-  <PropertyGroup Condition="'$(ReferenceSystemPrivateCoreLib)' == 'true' and '$(UsingMicrosoftNETSdk)' != 'true'">
-    <ProjectAssetsFile></ProjectAssetsFile>
-  </PropertyGroup>
-
   <PropertyGroup>
     <DisableImplicitFrameworkReferences>true</DisableImplicitFrameworkReferences>
   </PropertyGroup>

src/tests/Interop/COM/Activator/Activator.csproj

@@ -1,14 +1,14 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <!-- Internal.Runtime.InteropServices is CoreCLR-only -->
-    <ReferenceSystemPrivateCoreLib>true</ReferenceSystemPrivateCoreLib>
     <RequiresMockHostPolicy>true</RequiresMockHostPolicy>
     <!-- The test fails casting from ClassFromA from the default ALC to type IGetTypeFromC from a custom ALC -->
     <UnloadabilityIncompatible>true</UnloadabilityIncompatible>
+    <DisableProjectBuild Condition="'$(RuntimeFlavor)' == 'Mono'">true</DisableProjectBuild>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Program.cs" />
+    <Compile Include="ComActivationContextShim.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\NETServer\NETServer.csproj" />

src/tests/Interop/COM/Activator/ActivatorBuiltInComDisabled.csproj

@@ -1,14 +1,14 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <!-- Internal.Runtime.InteropServices is CoreCLR-only -->
-    <ReferenceSystemPrivateCoreLib>true</ReferenceSystemPrivateCoreLib>
     <RequiresMockHostPolicy>true</RequiresMockHostPolicy>
     <!-- The test fails casting from ClassFromA from the default ALC to type IGetTypeFromC from a custom ALC -->
     <UnloadabilityIncompatible>true</UnloadabilityIncompatible>
+    <DisableProjectBuild Condition="'$(RuntimeFlavor)' == 'Mono'">true</DisableProjectBuild>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Program.cs" />
+    <Compile Include="ComActivationContextShim.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\NETServer\NETServer.csproj" />

src/tests/Interop/COM/Activator/ComActivationContextShim.cs

@@ -0,0 +1,46 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Reflection;
+
+namespace Activator
+{
+    internal sealed class ComActivationContextShim
+    {
+        private static readonly Type _comActivationContextType = typeof(object).Assembly.GetType("Internal.Runtime.InteropServices.ComActivationContext", throwOnError: true);
+        private static readonly FieldInfo _classIdField = _comActivationContextType.GetField("ClassId");
+        private static readonly FieldInfo _interfaceIdField = _comActivationContextType.GetField("InterfaceId");
+        private static readonly FieldInfo _assemblyPathField = _comActivationContextType.GetField("AssemblyPath");
+        private static readonly FieldInfo _assemblyNameField = _comActivationContextType.GetField("AssemblyName");
+        private static readonly FieldInfo _typeNameField = _comActivationContextType.GetField("TypeName");
+
+        public object UnderlyingContext { get; } = System.Activator.CreateInstance(_comActivationContextType);
+
+        public Guid ClassId
+        {
+            get => (Guid)_classIdField.GetValue(UnderlyingContext);
+            set => _classIdField.SetValue(UnderlyingContext, value);
+        }
+        public Guid InterfaceId
+        {
+            get => (Guid)_interfaceIdField.GetValue(UnderlyingContext);
+            set => _interfaceIdField.SetValue(UnderlyingContext, value);
+        }
+        public string AssemblyPath
+        {
+            get => (string)_assemblyPathField.GetValue(UnderlyingContext);
+            set => _assemblyPathField.SetValue(UnderlyingContext, value);
+        }
+        public string AssemblyName
+        {
+            get => (string)_assemblyNameField.GetValue(UnderlyingContext);
+            set => _assemblyNameField.SetValue(UnderlyingContext, value);
+        }
+        public string TypeName
+        {
+            get => (string)_typeNameField.GetValue(UnderlyingContext);
+            set => _typeNameField.SetValue(UnderlyingContext, value);
+        }
+    }
+}

src/tests/Interop/COM/Activator/Program.cs

@@ -1,21 +1,48 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
+using System;
+using System.IO;
+using System.Reflection;
+using System.Runtime.InteropServices;
 
-namespace Activator
-{
-    using Internal.Runtime.InteropServices;
+using Internal.Runtime.InteropServices;
+using TestLibrary;
+using Xunit;
 
-    using System;
-    using System.IO;
-    using System.Runtime.InteropServices;
-
-    using TestLibrary;
-    using Xunit;
+namespace Internal.Runtime.InteropServices
+{
+    [ComImport]
+    [TypeIdentifier]
+    [ComVisible(false)]
+    [Guid("00000001-0000-0000-C000-000000000046")]
+    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+    public interface IClassFactory
+    {
+        void CreateInstance(
+            [MarshalAs(UnmanagedType.Interface)] object pUnkOuter,
+            ref Guid riid,
+            out IntPtr ppvObject);
 
-    using Console = Internal.Console;
+        void LockServer([MarshalAs(UnmanagedType.Bool)] bool fLock);
+    }
+}
 
+namespace Activator
+{
     class Program
     {
+        private static MethodInfo GetClassFactoryForTypeMethod = typeof(object).Assembly.GetType("Internal.Runtime.InteropServices.ComActivator", throwOnError: true).GetMethod("GetClassFactoryForType");
+        private static MethodInfo ClassRegistrationScenarioForTypeMethod = typeof(object).Assembly.GetType("Internal.Runtime.InteropServices.ComActivator", throwOnError: true).GetMethod("ClassRegistrationScenarioForType");
+
+        private static object GetClassFactoryForType(ComActivationContextShim context)
+        {
+            return GetClassFactoryForTypeMethod.Invoke(null, BindingFlags.DoNotWrapExceptions, binder: null, new[] { context.UnderlyingContext }, culture: null);
+        }
+        private static object ClassRegistrationScenarioForType(ComActivationContextShim context, bool register)
+        {
+            return ClassRegistrationScenarioForTypeMethod.Invoke(null, BindingFlags.DoNotWrapExceptions, binder: null, new[] { context.UnderlyingContext, (object)register }, culture: null);
+        }
+
         static void InvalidInterfaceRequest()
         {
             Console.WriteLine($"Running {nameof(InvalidInterfaceRequest)}...");
@@ -24,11 +51,11 @@ static void InvalidInterfaceRequest()
                 () =>
                 {
                     var notIClassFactory = new Guid("ED53F949-63E4-43B5-A13D-5655478AADD5");
-                    var cxt = new ComActivationContext()
+                    var cxt = new ComActivationContextShim()
                     {
                         InterfaceId = notIClassFactory
                     };
-                    ComActivator.GetClassFactoryForType(cxt);
+                    GetClassFactoryForType(cxt);
                 });
         }
 
@@ -38,12 +65,12 @@ static void NonrootedAssemblyPath(bool builtInComDisabled)
 
             Action action = () =>
                 {
-                    var cxt = new ComActivationContext()
+                    var cxt = new ComActivationContextShim()
                     {
                         InterfaceId = typeof(IClassFactory).GUID,
                         AssemblyPath = "foo.dll"
                     };
-                    ComActivator.GetClassFactoryForType(cxt);
+                    GetClassFactoryForType(cxt);
                 };
 
             if (!builtInComDisabled)
@@ -63,13 +90,13 @@ static void ClassNotRegistered(bool builtInComDisabled)
             Action action = () =>
                 {
                     var CLSID_NotRegistered = new Guid("328FF83E-3F6C-4BE9-A742-752562032925"); // Random GUID
-                    var cxt = new ComActivationContext()
+                    var cxt = new ComActivationContextShim()
                     {
                         ClassId = CLSID_NotRegistered,
                         InterfaceId = typeof(IClassFactory).GUID,
                         AssemblyPath = @"C:\foo.dll"
                     };
-                    ComActivator.GetClassFactoryForType(cxt);
+                    GetClassFactoryForType(cxt);
                 };
 
             if (!builtInComDisabled)
@@ -107,7 +134,7 @@ static void ValidateAssemblyIsolation(bool builtInComDisabled)
                 string.Empty,
                 string.Empty))
             {
-                var cxt = new ComActivationContext()
+                var cxt = new ComActivationContextShim()
                 {
                     ClassId = CLSID_NotUsed,
                     InterfaceId = typeof(IClassFactory).GUID,
@@ -119,11 +146,11 @@ static void ValidateAssemblyIsolation(bool builtInComDisabled)
                 if (builtInComDisabled)
                 {
                     Assert.Throws<NotSupportedException>(
-                        () => ComActivator.GetClassFactoryForType(cxt));
+                        () => GetClassFactoryForType(cxt));
                     return;
                 }
 
-                var factory = (IClassFactory)ComActivator.GetClassFactoryForType(cxt);
+                var factory = (IClassFactory)GetClassFactoryForType(cxt);
 
                 IntPtr svrRaw;
                 factory.CreateInstance(null, ref iid, out svrRaw);
@@ -138,7 +165,7 @@ static void ValidateAssemblyIsolation(bool builtInComDisabled)
                 string.Empty,
                 string.Empty))
             {
-                var cxt = new ComActivationContext()
+                var cxt = new ComActivationContextShim()
                 {
                     ClassId = CLSID_NotUsed,
                     InterfaceId = typeof(IClassFactory).GUID,
@@ -147,7 +174,7 @@ static void ValidateAssemblyIsolation(bool builtInComDisabled)
                     TypeName = "ClassFromB"
                 };
 
-                var factory = (IClassFactory)ComActivator.GetClassFactoryForType(cxt);
+                var factory = (IClassFactory)GetClassFactoryForType(cxt);
 
                 IntPtr svrRaw;
                 factory.CreateInstance(null, ref iid, out svrRaw);
@@ -191,7 +218,7 @@ static void ValidateUserDefinedRegistrationCallbacks()
                 {
                     Console.WriteLine($"Validating {typeName}...");
 
-                    var cxt = new ComActivationContext()
+                    var cxt = new ComActivationContextShim()
                     {
                         ClassId = CLSID_NotUsed,
                         InterfaceId = typeof(IClassFactory).GUID,
@@ -200,7 +227,7 @@ static void ValidateUserDefinedRegistrationCallbacks()
                         TypeName = typeName
                     };
 
-                    var factory = (IClassFactory)ComActivator.GetClassFactoryForType(cxt);
+                    var factory = (IClassFactory)GetClassFactoryForType(cxt);
 
                     IntPtr svrRaw;
                     factory.CreateInstance(null, ref iid, out svrRaw);
@@ -212,8 +239,8 @@ static void ValidateUserDefinedRegistrationCallbacks()
                     Assert.False(inst.DidUnregister());
 
                     cxt.InterfaceId = Guid.Empty;
-                    ComActivator.ClassRegistrationScenarioForType(cxt, register: true);
-                    ComActivator.ClassRegistrationScenarioForType(cxt, register: false);
+                    ClassRegistrationScenarioForType(cxt, register: true);
+                    ClassRegistrationScenarioForType(cxt, register: false);
 
                     Assert.True(inst.DidRegister(), $"User-defined register function should have been called.");
                     Assert.True(inst.DidUnregister(), $"User-defined unregister function should have been called.");
@@ -230,7 +257,7 @@ static void ValidateUserDefinedRegistrationCallbacks()
                 {
                     Console.WriteLine($"Validating {typename}...");
 
-                    var cxt = new ComActivationContext()
+                    var cxt = new ComActivationContextShim()
                     {
                         ClassId = CLSID_NotUsed,
                         InterfaceId = typeof(IClassFactory).GUID,
@@ -239,7 +266,7 @@ static void ValidateUserDefinedRegistrationCallbacks()
                         TypeName = typename
                     };
 
-                    var factory = (IClassFactory)ComActivator.GetClassFactoryForType(cxt);
+                    var factory = (IClassFactory)GetClassFactoryForType(cxt);
 
                     IntPtr svrRaw;
                     factory.CreateInstance(null, ref iid, out svrRaw);
@@ -251,7 +278,7 @@ static void ValidateUserDefinedRegistrationCallbacks()
                     bool exceptionThrown = false;
                     try
                     {
-                        ComActivator.ClassRegistrationScenarioForType(cxt, register: true);
+                        ClassRegistrationScenarioForType(cxt, register: true);
                     }
                     catch
                     {
@@ -263,7 +290,7 @@ static void ValidateUserDefinedRegistrationCallbacks()
                     exceptionThrown = false;
                     try
                     {
-                        ComActivator.ClassRegistrationScenarioForType(cxt, register: false);
+                        ClassRegistrationScenarioForType(cxt, register: false);
                     }
                     catch
                     {