Guard MarshalByRefObject, [Serializable], and InitializeLifetimeService behind #if NETFRAMEWORK

src/Adapter/MSTest.TestAdapter/TestingPlatformAdapter/MTPTraceLogger.cs

@@ -8,7 +8,11 @@
 namespace Microsoft.VisualStudio.TestTools.UnitTesting;
 
 [SuppressMessage("ApiDesign", "RS0030:Do not use banned APIs", Justification = "MTP logger bridge")]
-internal sealed class MTPTraceLogger : MarshalByRefObject, ITraceLogger
+internal sealed class MTPTraceLogger :
+#if NETFRAMEWORK
+    MarshalByRefObject,
+#endif
+    ITraceLogger
 {
     private readonly ILogger _logger;
 

src/Adapter/MSTest.TestAdapter/VSTestAdapter/EqtTraceLogger.cs

@@ -6,7 +6,11 @@
 
 namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.VSTestAdapter;
 
-internal sealed class EqtTraceLogger : MarshalByRefObject, ITraceLogger
+internal sealed class EqtTraceLogger :
+#if NETFRAMEWORK
+    MarshalByRefObject,
+#endif
+    ITraceLogger
 {
     private EqtTraceLogger()
     {

src/Adapter/MSTestAdapter.PlatformServices/Deployment/DeploymentItem.cs

@@ -10,7 +10,9 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTestAdapter.PlatformServices.Dep
 /// <summary>
 /// Specifies type of deployment item origin, where the item comes from.
 /// </summary>
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal enum DeploymentItemOriginType
 {
     /// <summary>
@@ -37,7 +39,9 @@ internal enum DeploymentItemOriginType
 /// <summary>
 /// The deployment item for a test class or a test method.
 /// </summary>
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal sealed class DeploymentItem
 {
     /// <summary>

src/Adapter/MSTestAdapter.PlatformServices/Deployment/TestRunDirectories.cs

@@ -10,7 +10,9 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTestAdapter.PlatformServices.Dep
 /// <summary>
 /// The test run directories.
 /// </summary>
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal sealed class TestRunDirectories
 {
     /// <summary>

src/Adapter/MSTestAdapter.PlatformServices/Discovery/AssemblyEnumerationResult.cs

@@ -10,5 +10,7 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Discovery;
 /// </summary>
 /// <param name="TestElements">The test elements that were discovered.</param>
 /// <param name="Warnings">Warnings that happened during discovery.</param>
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal sealed record AssemblyEnumerationResult(List<UnitTestElement> TestElements, List<string> Warnings);

src/Adapter/MSTestAdapter.PlatformServices/Discovery/AssemblyEnumerator.cs

@@ -1,8 +1,12 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+// Note: System.Runtime.Serialization is intentionally unconditional — SerializationException is caught
+// outside the #if NETFRAMEWORK block (see catch in EnumerateAssembly).
 using System.Runtime.Serialization;
+#if NETFRAMEWORK
 using System.Security;
+#endif
 
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Execution;
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Helpers;
@@ -16,7 +20,10 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Discovery;
 /// Enumerates through all types in the assembly in search of valid test methods.
 /// </summary>
 [SuppressMessage("Performance", "CA1852: Seal internal types", Justification = "Overrides required for testability")]
-internal class AssemblyEnumerator : MarshalByRefObject
+internal class AssemblyEnumerator
+#if NETFRAMEWORK
+    : MarshalByRefObject
+#endif
 {
     /// <summary>
     /// Helper for reflection API's.
@@ -45,17 +52,16 @@ public AssemblyEnumerator(MSTestSettings settings) =>
         // This would just be resetting the settings to itself in non desktop workflows.
         MSTestSettings.PopulateSettings(settings);
 
+#if NETFRAMEWORK
     /// <summary>
     /// Returns object to be used for controlling lifetime, null means infinite lifetime.
     /// </summary>
     /// <returns>
     /// The <see cref="object"/>.
     /// </returns>
     [SecurityCritical]
-#if NET5_0_OR_GREATER
-    [Obsolete("MarshalByRefObject.InitializeLifetimeService is obsolete in .NET 5+. This override is required to maintain infinite lifetime service.")]
+    public override object? InitializeLifetimeService() => null;
 #endif
-    public override object InitializeLifetimeService() => null!;
 
     /// <summary>
     /// Enumerates through all types in the assembly in search of valid test methods.

src/Adapter/MSTestAdapter.PlatformServices/Execution/TestAssemblySettingsProvider.cs

@@ -1,27 +1,31 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+#if NETFRAMEWORK
 using System.Security;
+#endif
 
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Helpers;
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.ObjectModel;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
 namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Execution;
 
-internal sealed class TestAssemblySettingsProvider : MarshalByRefObject
+internal sealed class TestAssemblySettingsProvider
+#if NETFRAMEWORK
+    : MarshalByRefObject
+#endif
 {
+#if NETFRAMEWORK
     /// <summary>
     /// Returns object to be used for controlling lifetime, null means infinite lifetime.
     /// </summary>
     /// <returns>
     /// The <see cref="object"/>.
     /// </returns>
     [SecurityCritical]
-#if NET5_0_OR_GREATER
-    [Obsolete("MarshalByRefObject.InitializeLifetimeService is obsolete in .NET 5+. This override is required to maintain infinite lifetime service.")]
+    public override object? InitializeLifetimeService() => null;
 #endif
-    public override object InitializeLifetimeService() => null!;
 
     [SuppressMessage(
         "Performance",

src/Adapter/MSTestAdapter.PlatformServices/Execution/TestExecutionManager.cs

@@ -21,7 +21,11 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Execution;
 #pragma warning disable CA1852 // Seal internal types - This class is inherited in tests.
 internal class TestExecutionManager
 {
-    private sealed class RemotingMessageLogger : MarshalByRefObject, IMessageLogger
+    private sealed class RemotingMessageLogger :
+#if NETFRAMEWORK
+        MarshalByRefObject,
+#endif
+        IMessageLogger
     {
         private readonly IMessageLogger _realMessageLogger;
 

src/Adapter/MSTestAdapter.PlatformServices/Execution/TypeCache.cs

@@ -1,7 +1,9 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+#if NETFRAMEWORK
 using System.Security;
+#endif
 
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Discovery;
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Extensions;
@@ -15,7 +17,10 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Execution;
 /// <summary>
 /// Defines type cache which reflects upon a type and cache its test artifacts.
 /// </summary>
-internal sealed class TypeCache : MarshalByRefObject
+internal sealed class TypeCache
+#if NETFRAMEWORK
+    : MarshalByRefObject
+#endif
 {
     /// <summary>
     /// Helper for reflection API's.
@@ -108,17 +113,16 @@ public IEnumerable<TestAssemblyInfo> AssemblyInfoListWithExecutableCleanupMethod
         return ResolveTestMethodInfoForDiscovery(testMethod, testClassInfo);
     }
 
+#if NETFRAMEWORK
     /// <summary>
     /// Returns object to be used for controlling lifetime, null means infinite lifetime.
     /// </summary>
     /// <returns>
     /// The <see cref="object"/>.
     /// </returns>
     [SecurityCritical]
-#if NET5_0_OR_GREATER
-    [Obsolete("MarshalByRefObject.InitializeLifetimeService is obsolete in .NET 5+. This override is required to maintain infinite lifetime service.")]
+    public override object? InitializeLifetimeService() => null;
 #endif
-    public override object InitializeLifetimeService() => null!;
 
     #region ClassInfo creation and cache logic.
 

src/Adapter/MSTestAdapter.PlatformServices/Execution/UnitTestRunner.cs

@@ -1,7 +1,9 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+#if NETFRAMEWORK
 using System.Security;
+#endif
 
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Extensions;
 using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Helpers;
@@ -18,7 +20,10 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Execution;
 /// <summary>
 /// The runner that runs a single unit test. Also manages the assembly and class cleanup methods at the end of the run.
 /// </summary>
-internal sealed class UnitTestRunner : MarshalByRefObject
+internal sealed class UnitTestRunner
+#if NETFRAMEWORK
+    : MarshalByRefObject
+#endif
 {
     private readonly TypeCache _typeCache;
     private readonly ClassCleanupManager _classCleanupManager;
@@ -75,17 +80,16 @@ public void Cancel()
         => PlatformServiceProvider.Instance.TestRunCancellationToken?.Cancel();
 #pragma warning restore CA1822 // Mark members as static
 
+#if NETFRAMEWORK
     /// <summary>
     /// Returns object to be used for controlling lifetime, null means infinite lifetime.
     /// </summary>
     /// <returns>
     /// The <see cref="object"/>.
     /// </returns>
     [SecurityCritical]
-#if NET5_0_OR_GREATER
-    [Obsolete("MarshalByRefObject.InitializeLifetimeService is obsolete in .NET 5+. This override is required to maintain infinite lifetime service.")]
+    public override object? InitializeLifetimeService() => null;
 #endif
-    public override object InitializeLifetimeService() => null!;
 
     // Task cannot cross app domains.
     // For now, TestExecutionManager will call this sync method which is hacky.

src/Adapter/MSTestAdapter.PlatformServices/Helpers/ReflectHelper.cs

@@ -1,15 +1,20 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+#if NETFRAMEWORK
 using System.Security;
+#endif
 
 using Microsoft.VisualStudio.TestPlatform.ObjectModel;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
 namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Helpers;
 
 [SuppressMessage("Performance", "CA1852: Seal internal types", Justification = "Overrides required for mocking")]
-internal class ReflectHelper : MarshalByRefObject
+internal class ReflectHelper
+#if NETFRAMEWORK
+    : MarshalByRefObject
+#endif
 {
 #pragma warning disable RS0030 // Do not use banned APIs
     private static readonly Lazy<ReflectHelper> InstanceValue = new(() => new());
@@ -53,17 +58,16 @@ internal class ReflectHelper : MarshalByRefObject
         return false;
     }
 
+#if NETFRAMEWORK
     /// <summary>
     /// Returns object to be used for controlling lifetime, null means infinite lifetime.
     /// </summary>
     /// <returns>
     /// The <see cref="object"/>.
     /// </returns>
     [SecurityCritical]
-#if NET5_0_OR_GREATER
-    [Obsolete("MarshalByRefObject.InitializeLifetimeService is obsolete in .NET 5+. This override is required to maintain infinite lifetime service.")]
+    public override object? InitializeLifetimeService() => null;
 #endif
-    public override object InitializeLifetimeService() => null!;
 
     /// <summary>
     /// Gets first attribute that matches the type.

src/Adapter/MSTestAdapter.PlatformServices/MSTestSettings.cs

@@ -9,7 +9,9 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter;
 /// <summary>
 /// Adapter Settings for the run.
 /// </summary>
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal sealed partial class MSTestSettings
 {
     /// <summary>
@@ -24,16 +26,6 @@ internal sealed partial class MSTestSettings
 
     private const string ParallelizeSettingsName = "Parallelize";
 
-    /// <summary>
-    /// Member variable for Adapter settings.
-    /// </summary>
-    private static MSTestSettings? s_currentSettings;
-
-    /// <summary>
-    /// Member variable for RunConfiguration settings.
-    /// </summary>
-    private static RunConfigurationSettings? s_runConfigurationSettings;
-
     /// <summary>
     /// Initializes a new instance of the <see cref="MSTestSettings"/> class.
     /// </summary>
@@ -60,21 +52,25 @@ public MSTestSettings()
     /// <summary>
     /// Gets the current settings.
     /// </summary>
+    [field: AllowNull]
+    [field: MaybeNull]
     [AllowNull]
     public static MSTestSettings CurrentSettings
     {
-        get => s_currentSettings ??= new MSTestSettings();
-        private set => s_currentSettings = value;
+        get => field ??= new MSTestSettings();
+        private set;
     }
 
     /// <summary>
     /// Gets the current configuration settings.
     /// </summary>
+    [field: AllowNull]
+    [field: MaybeNull]
     [AllowNull]
     public static RunConfigurationSettings RunConfigurationSettings
     {
-        get => s_runConfigurationSettings ??= new RunConfigurationSettings();
-        private set => s_runConfigurationSettings = value;
+        get => field ??= new RunConfigurationSettings();
+        private set;
     }
 
     /// <summary>

src/Adapter/MSTestAdapter.PlatformServices/NopTraceLogger.cs

@@ -5,7 +5,11 @@
 
 namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter;
 
-internal sealed class NopTraceLogger : MarshalByRefObject, ITraceLogger
+internal sealed class NopTraceLogger :
+#if NETFRAMEWORK
+    MarshalByRefObject,
+#endif
+    ITraceLogger
 {
     private NopTraceLogger()
     {

src/Adapter/MSTestAdapter.PlatformServices/ObjectModel/StackTraceInformation.cs

@@ -5,7 +5,9 @@
 
 namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.ObjectModel;
 
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal sealed class StackTraceInformation
 {
     public StackTraceInformation(string stackTrace)

src/Adapter/MSTestAdapter.PlatformServices/ObjectModel/TestAssemblySettings.cs

@@ -5,7 +5,9 @@
 
 namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.ObjectModel;
 
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal sealed class TestAssemblySettings
 {
     public TestAssemblySettings() => Workers = -1;

src/Adapter/MSTestAdapter.PlatformServices/ObjectModel/TestMethod.cs

@@ -13,7 +13,9 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.ObjectModel;
 /// <summary>
 /// TestMethod contains information about a unit test method that needs to be executed.
 /// </summary>
+#if NETFRAMEWORK
 [Serializable]
+#endif
 internal sealed class TestMethod : ITestMethod
 {
     /// <summary>
@@ -101,10 +103,14 @@ internal TestMethod(
     // This holds user types that may not be serializable.
     // If app domains are enabled, we have no choice other than losing the original data.
     // In that case, we fallback to deserializing the SerializedData.
+#if NETFRAMEWORK
     [field: NonSerialized]
+#endif
     internal object?[]? ActualData { get; set; }
 
+#if NETFRAMEWORK
     [field: NonSerialized]
+#endif
     internal MethodInfo? MethodInfo { get; set; }
 
     /// <summary>