Block casting to an interface marked ComInterfaceType.InterfaceIsIInspectable

src/coreclr/src/vm/runtimecallablewrapper.cpp

@@ -2633,6 +2633,11 @@ BOOL ComObject::SupportsInterface(OBJECTREF oref, MethodTable* pIntfTable)
     // Make sure the interface method table has been restored.
     pIntfTable->CheckRestore();
 
+    if (pIntfTable->GetComInterfaceType() == ifInspectable)
+    {
+        COMPlusThrow(kPlatformNotSupportedException, IDS_EE_NO_IINSPECTABLE);
+    }
+
     // Check to see if the static class definition indicates we implement the interface.
     MethodTable *pMT = oref->GetMethodTable();
     if (pMT->CanCastToInterface(pIntfTable))

src/tests/Interop/COM/NETClients/IInspectable/App.manifest

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<assembly manifestVersion="1.0" xmlns="urn:schemas-microsoft-com:asm.v1">
+  <assemblyIdentity
+    type="win32" 
+    name="NetPrimitivesIInspectable"
+    version="1.0.0.0" />
+
+  <dependency>
+    <dependentAssembly>
+      <!-- RegFree COM -->
+      <assemblyIdentity
+          type="win32"
+          name="COMNativeServer.X"
+          version="1.0.0.0"/>
+    </dependentAssembly>
+  </dependency>
+
+</assembly>

src/tests/Interop/COM/NETClients/IInspectable/NETClientIInspectable.csproj

@@ -0,0 +1,22 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <ApplicationManifest>App.manifest</ApplicationManifest>
+    <!-- ilasm round-trip testing blocked on ILAsm supporting embedding resources. See https://github.com/dotnet/runtime/issues/11412 -->
+    <IlasmRoundTripIncompatible>true</IlasmRoundTripIncompatible>
+    <!-- Test unsupported outside of windows -->
+    <CLRTestTargetUnsupported Condition="'$(TargetsWindows)' != 'true'">true</CLRTestTargetUnsupported>
+    <!-- This test would require the runincontext.exe to include App.manifest describing the COM interfaces -->
+    <UnloadabilityIncompatible>true</UnloadabilityIncompatible>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="Program.cs" />
+    <Compile Include="../../ServerContracts/Server.CoClasses.cs" />
+    <Compile Include="../../ServerContracts/Server.Contracts.cs" />
+    <Compile Include="../../ServerContracts/ServerGuids.cs" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="../../NativeServer/CMakeLists.txt" />
+    <ProjectReference Include="$(TestSourceDir)Common/CoreCLRTestLibrary/CoreCLRTestLibrary.csproj" />
+  </ItemGroup>
+</Project>

src/tests/Interop/COM/NETClients/IInspectable/Program.cs

@@ -0,0 +1,44 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace NetClient
+{
+    using System;
+    using System.Globalization;
+    using System.Reflection;
+    using System.Runtime.InteropServices;
+
+    using TestLibrary;
+    using Server.Contract;
+    using Server.Contract.Servers;
+
+    class Program
+    {
+        static void Validate_IInspectable()
+        {
+            var server = (InspectableTesting)new InspectableTestingClass();
+            Assert.Throws<PlatformNotSupportedException>(() => _ = (IInspectableTesting2)server);
+        }
+
+        static int Main(string[] doNotUse)
+        {
+            // RegFree COM is not supported on Windows Nano
+            if (Utilities.IsWindowsNanoServer)
+            {
+                return 100;
+            }
+
+            try
+            {
+                Validate_IInspectable();
+            }
+            catch (Exception e)
+            {
+                Console.WriteLine($"Test Failure: {e}");
+                return 101;
+            }
+
+            return 100;
+        }
+    }
+}

src/tests/Interop/COM/NativeServer/COMNativeServer.X.manifest

@@ -51,6 +51,11 @@
   <comClass
     clsid="{66DB7882-E2B0-471D-92C7-B2B52A0EA535}"
     threadingModel="Both" />
+
+  <!-- InspectableTesting -->
+  <comClass
+    clsid="{CE137261-6F19-44F5-A449-EF963B3F987E}"
+    threadingModel="Both" />
 </file>
 
 </assembly>

src/tests/Interop/COM/NativeServer/InspectableTesting.h

@@ -0,0 +1,51 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#pragma once
+
+#include "Servers.h"
+
+class InspectableTesting : public UnknownImpl, public IInspectableTesting, public IInspectableTesting2
+{
+public: // IInspectableTesting2
+    DEF_FUNC(Add)(
+        /*[in]*/ int a,
+        /*[in]*/ int b,
+        /*[out] [retval] */ int* retVal)
+    {
+        *retVal = a + b;
+        return S_OK;
+    }
+
+public: // IInspectable
+    STDMETHOD(GetIids)( 
+        /* [out] */ ULONG *iidCount,
+        /* [size_is][size_is][out] */ IID **iids)
+    {
+        return E_NOTIMPL;
+    }
+
+    STDMETHOD(GetRuntimeClassName)( 
+        /* [out] */ HSTRING *className)
+    {
+        className = nullptr;
+        return S_OK;
+    }
+
+    STDMETHOD(GetTrustLevel)( 
+        /* [out] */ TrustLevel *trustLevel)
+    {
+        *trustLevel = TrustLevel::FullTrust;
+        return S_OK;
+    }
+
+public: // IUnknown
+    STDMETHOD(QueryInterface)(
+        /* [in] */ REFIID riid,
+        /* [iid_is][out] */ _COM_Outptr_ void __RPC_FAR *__RPC_FAR *ppvObject)
+    {
+        return DoQueryInterface(riid, ppvObject, static_cast<IInspectableTesting *>(this), static_cast<IInspectableTesting2 *>(this), static_cast<IInspectable*>(this));
+    }
+
+    DEFINE_REF_COUNTING();
+};

src/tests/Interop/COM/NativeServer/Servers.cpp

@@ -167,6 +167,7 @@ STDAPI DllRegisterServer(void)
     RETURN_IF_FAILED(RegisterClsid(__uuidof(EventTesting), L"Both"));
     RETURN_IF_FAILED(RegisterClsid(__uuidof(AggregationTesting), L"Both"));
     RETURN_IF_FAILED(RegisterClsid(__uuidof(ColorTesting), L"Both"));
+    RETURN_IF_FAILED(RegisterClsid(__uuidof(InspectableTesting), L"Both"));
 
     return S_OK;
 }
@@ -183,6 +184,7 @@ STDAPI DllUnregisterServer(void)
     RETURN_IF_FAILED(RemoveClsid(__uuidof(EventTesting)));
     RETURN_IF_FAILED(RemoveClsid(__uuidof(AggregationTesting)));
     RETURN_IF_FAILED(RemoveClsid(__uuidof(ColorTesting)));
+    RETURN_IF_FAILED(RemoveClsid(__uuidof(InspectableTesting)));
 
     return S_OK;
 }
@@ -216,5 +218,8 @@ STDAPI DllGetClassObject(_In_ REFCLSID rclsid, _In_ REFIID riid, _Out_ LPVOID FA
     if (rclsid == __uuidof(LicenseTesting))
         return ClassFactoryLicense<LicenseTesting>::Create(riid, ppv);
 
+    if (rclsid == __uuidof(InspectableTesting))
+        return ClassFactoryBasic<InspectableTesting>::Create(riid, ppv);
+
     return CLASS_E_CLASSNOTAVAILABLE;
 }

src/tests/Interop/COM/NativeServer/Servers.h

@@ -19,6 +19,7 @@ class DECLSPEC_UUID("4CEFE36D-F377-4B6E-8C34-819A8BB9CB04") AggregationTesting;
 class DECLSPEC_UUID("C222F472-DA5A-4FC6-9321-92F4F7053A65") ColorTesting;
 class DECLSPEC_UUID("66DB7882-E2B0-471D-92C7-B2B52A0EA535") LicenseTesting;
 class DECLSPEC_UUID("FAEF42AE-C1A4-419F-A912-B768AC2679EA") DefaultInterfaceTesting;
+class DECLSPEC_UUID("CE137261-6F19-44F5-A449-EF963B3F987E") InspectableTesting;
 
 #define CLSID_NumericTesting __uuidof(NumericTesting)
 #define CLSID_ArrayTesting __uuidof(ArrayTesting)
@@ -30,6 +31,7 @@ class DECLSPEC_UUID("FAEF42AE-C1A4-419F-A912-B768AC2679EA") DefaultInterfaceTest
 #define CLSID_ColorTesting __uuidof(ColorTesting)
 #define CLSID_LicenseTesting __uuidof(LicenseTesting)
 #define CLSID_DefaultInterfaceTesting __uuidof(DefaultInterfaceTesting)
+#define CLSID_InspectableTesting __uidof(InspectableTesting)
 
 #define IID_INumericTesting __uuidof(INumericTesting)
 #define IID_IArrayTesting __uuidof(IArrayTesting)
@@ -43,6 +45,8 @@ class DECLSPEC_UUID("FAEF42AE-C1A4-419F-A912-B768AC2679EA") DefaultInterfaceTest
 #define IID_ILicenseTesting __uuidof(ILicenseTesting)
 #define IID_IDefaultInterfaceTesting __uuidof(IDefaultInterfaceTesting)
 #define IID_IDefaultInterfaceTesting2 __uuidof(IDefaultInterfaceTesting2)
+#define IID_IInspectableTesting __uuidof(IInspectableTesting)
+#define IID_IInspectableTesting2 __uuidof(IInspectableTesting2)
 
 // Class used for COM activation when using CoreShim
 struct CoreShimComActivation
@@ -81,4 +85,5 @@ struct CoreShimComActivation
     #include "AggregationTesting.h"
     #include "ColorTesting.h"
     #include "LicenseTesting.h"
+    #include "InspectableTesting.h"
 #endif

src/tests/Interop/COM/ServerContracts/Server.CoClasses.cs

@@ -207,6 +207,19 @@ internal interface ConsumeNETServerTesting : Server.Contract.IConsumeNETServer
     internal class ConsumeNETServerTestingClass
     {
     }
+
+    [ComImport]
+    [CoClass(typeof(InspectableTestingClass))]
+    [Guid("3021236a-2a9e-4a29-bf14-533842c55262")]
+    internal interface InspectableTesting : Server.Contract.IInspectableTesting
+    {
+    }
+
+    [ComImport]
+    [Guid(Server.Contract.Guids.InspectableTesting)]
+    internal class InspectableTestingClass
+    {
+    }
 }
 
 #pragma warning restore 618 // Must test deprecated features

src/tests/Interop/COM/ServerContracts/Server.Contracts.cs

@@ -324,6 +324,21 @@ public interface IConsumeNETServer
         bool EqualByCCW(object obj);
         bool NotEqualByRCW(object obj);
     }
+
+    [ComVisible(true)]
+    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+    [Guid("3021236a-2a9e-4a29-bf14-533842c55262")]
+    internal interface IInspectableTesting
+    {
+    }
+
+    [ComImport]
+    [InterfaceType(ComInterfaceType.InterfaceIsIInspectable)]
+    [Guid("e9e1ccf9-8e93-4850-ac1c-a71692cb68c5")]
+    internal interface IInspectableTesting2
+    {
+        int Add(int i, int j);
+    }
 }
 
 #pragma warning restore 618 // Must test deprecated features

src/tests/Interop/COM/ServerContracts/Server.Contracts.h

@@ -4,6 +4,7 @@
 #pragma pack(push, 8)
 
 #include <comdef.h>
+#include <inspectable.h>
 
 struct HFA_4
 {
@@ -486,4 +487,15 @@ IDefaultInterfaceTesting2 : IUnknown
     // Empty
 };
 
+struct __declspec(uuid("3021236a-2a9e-4a29-bf14-533842c55262"))
+IInspectableTesting : IUnknown
+{
+};
+
+struct __declspec(uuid("e9e1ccf9-8e93-4850-ac1c-a71692cb68c5"))
+IInspectableTesting2 : IInspectable
+{
+    virtual HRESULT STDMETHODCALLTYPE Add(_In_ int i, _In_ int j, _Out_ _Ret_ int* retVal) = 0;
+};
+
 #pragma pack(pop)

src/tests/Interop/COM/ServerContracts/ServerGuids.cs

@@ -19,5 +19,6 @@ internal sealed class Guids
         public const string LicenseTesting = "66DB7882-E2B0-471D-92C7-B2B52A0EA535";
         public const string DefaultInterfaceTesting = "FAEF42AE-C1A4-419F-A912-B768AC2679EA";
         public const string ConsumeNETServerTesting = "DE4ACF53-5957-4D31-8BE2-EA6C80683246";
+        public const string InspectableTesting = "CE137261-6F19-44F5-A449-EF963B3F987E";
     }
 }