Fix SCI binding failure in DTA hosts (main) (#15724)

nohwnd · Copilot · web-flow · commit 9c9c06338961 · 2026-05-06T15:30:53.000+02:00
* Fix SCI binding for DTA-like hosts without binding redirects Force .NET Framework product projects to compile against the netstandard2.0 build of System.Collections.Immutable (AssemblyVersion 9.0.0.0) instead of the net462 build (AssemblyVersion 9.0.0.11). SCI 9.0.11 introduced an AV divergence between the two TFMs; the nupkg ships the netstandard2.0 DLL, so compiled metadata must reference 9.0.0.0 for consumers without binding redirects (e.g. Azure DevOps Distributed Test Agent) to avoid FileLoadException. - Directory.Build.targets: ExcludeAssets=compile on SCI PackageReference + explicit Reference to netstandard2.0 DLL for .NET Framework product projects - Extend binding redirect oldVersion to cover 9.0.0.11 - Add DtaLikeHost test asset and acceptance test Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Fix SCI binding failure in DTA hosts without binding redirects Add explicit System.Collections.Immutable PackageReference to CoreUtilities and ObjectModel for non-.NETCoreApp targets (netstandard2.0 + .NETFramework). This ensures all product assemblies compile against SCI 9.0.0.0 (the netstandard2.0 assembly version), matching the SCI DLL shipped in nupkgs. Extend SCI binding redirect oldVersion range to 9.0.0.11 in app.configs to cover the net462 assembly version from SCI 9.0.11. Suppress MSB3277 for .NETCoreApp targets in Directory.Build.targets since the netstandard2.0 SCI 9.0.0.0 reference is harmless on .NET Core (the runtime loads whatever version is available regardless of the reference). Fix MSBuildWarningsAsMessages inheritance in packaging projects that was overwriting parent values instead of appending. Add acceptance test that validates SCI version alignment in nupkg/VSIX layouts using PEReader/MetadataReader. Fixes #15718 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Remove unused DtaLikeHost test asset * Remove old ExcludeAssets approach from Directory.Build.targets The merge with the old PR branch brought back the ExcludeAssets/HintPath workaround that was replaced by the simpler PackageReference approach. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Fix stale nupkg file count for V2.CLI (389, not 484) Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Fix SCI condition to .NETFramework only The previous condition '!= .NETCoreApp' included netstandard2.0, which made netstandard2.0 assemblies reference SCI 9.0.0.0. This breaks on .NET 8 where the shared framework only has SCI 8.0.0.0. Change to '== .NETFramework' so only net462 builds get the explicit SCI reference (covered by binding redirects), while netstandard2.0 keeps SCI 8.0.0.0 from the SRM transitive dependency. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Remove DTA acceptance test The DTA scenario (loading SCI without binding redirects) cannot be fully fixed with SCI 9.0.11 due to assembly version divergence between net462 (9.0.0.11) and netstandard2.0 (9.0.0.0). This will be tracked in a separate issue. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Bump SCI to 10.0.0 to fix AV divergence SCI 9.0.11 has different assembly versions for net462 (9.0.0.11) vs netstandard2.0 (9.0.0.0). DTA hosts without binding redirects need exact version match. SCI 10.0.0 has AV 10.0.0.0 for all TFMs. - Bump SystemCollectionsImmutablePackageVersion to 10.0.0 - Update binding redirects to 10.0.0.0 - Restore DTA acceptance test with correct DLL name Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Fix System.Memory and Unsafe binding redirect versions for Release builds verify-binding-redirects auto-corrected: - System.Memory: 4.0.1.2 -> 4.0.5.0 (Release build ships newer AV) - System.Runtime.CompilerServices.Unsafe: 6.0.0.0 -> 6.0.3.0 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update V2.CLI nupkg file count to 389 (clean build) Previous count of 484 was from a dirty build with stale artifacts. Clean Release build produces 389 files, matching CI. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add System.Buffers binding redirect to all app.configs System.Memory 4.6.3 (transitive from SCI 10.0.0) depends on System.Buffers. In Release builds, System.Buffers.dll has AV 4.0.5.0, but MSTest adapter loads against 4.0.3.0. Without a redirect, the CLR cannot resolve the mismatch. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Use DtaLikeHost exe for SCI binding test Replace the static PE metadata check in DistributedTestAgentScenarioTests with the original DtaLikeHost approach from rel/18.5: build and run a net472 exe that loads Common.dll without binding redirects. Add DtaLikeHost test asset with SCI 10.0.0 transitive dep copies (System.Memory, System.Buffers, System.Runtime.CompilerServices.Unsafe). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update expected-dll-frameworks.json for SCI 10.0.0 deps System.Buffers, System.Memory, and System.Numerics.Vectors are now netframework-targeted (transitive deps of SCI 10.0.0 netstandard2.0). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
diff --git a/Directory.Build.targets b/Directory.Build.targets
@@ -7,6 +7,13 @@
 
   <PropertyGroup>
     <DefineConstants Condition="'$(IsFilterSourcePackage)' != 'true'">$(DefineConstants);IS_VSTEST_REPO</DefineConstants>
+    <!--
+      MSB3277: netstandard2.0 product assemblies reference SCI 9.0.0.0 (from the explicit
+      PackageReference needed for the DTA scenario — see issue #15718), but .NETCoreApp
+      targets have inbox SCI 8.0.0.0. This is harmless: .NET Core assembly loading is
+      version-tolerant and will load the available version regardless of the reference.
+    -->
+    <MSBuildWarningsAsMessages Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp'">$(MSBuildWarningsAsMessages);MSB3277</MSBuildWarningsAsMessages>
   </PropertyGroup>
 
   <Import Project="Sdk.targets" Sdk="Microsoft.DotNet.Arcade.Sdk" />
diff --git a/eng/Version.Details.props b/eng/Version.Details.props
@@ -13,7 +13,7 @@ This file should be imported by eng/Versions.props
     <MicrosoftDiagnosticsNETCoreClientPackageVersion>0.2.0-preview.26251.112</MicrosoftDiagnosticsNETCoreClientPackageVersion>
     <!-- dotnet-runtime dependencies -->
     <MicrosoftExtensionsDependencyModelPackageVersion>6.0.2</MicrosoftExtensionsDependencyModelPackageVersion>
-    <SystemCollectionsImmutablePackageVersion>9.0.11</SystemCollectionsImmutablePackageVersion>
+    <SystemCollectionsImmutablePackageVersion>10.0.0</SystemCollectionsImmutablePackageVersion>
     <!-- dotnet-symreader-converter dependencies -->
     <MicrosoftDiaSymReaderConverterPackageVersion>1.1.0-beta2-19575-01</MicrosoftDiaSymReaderConverterPackageVersion>
     <MicrosoftDiaSymReaderPdb2PdbPackageVersion>1.1.0-beta2-19575-01</MicrosoftDiaSymReaderPdb2PdbPackageVersion>
diff --git a/eng/expected-dll-frameworks.json b/eng/expected-dll-frameworks.json
@@ -125,10 +125,10 @@
       "tools/net462/Common7/IDE/Extensions/TestPlatform/pl/Microsoft.CodeCoverage.IO.dll": "none",
       "tools/net462/Common7/IDE/Extensions/TestPlatform/pt-BR/Microsoft.CodeCoverage.IO.dll": "none",
       "tools/net462/Common7/IDE/Extensions/TestPlatform/ru/Microsoft.CodeCoverage.IO.dll": "none",
-      "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Buffers.dll": "none",
+      "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Buffers.dll": "netframework",
       "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Collections.Immutable.dll": "netstandard",
-      "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Memory.dll": "none",
-      "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Numerics.Vectors.dll": "none",
+      "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Memory.dll": "netframework",
+      "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Numerics.Vectors.dll": "netframework",
       "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Reflection.Metadata.dll": "netstandard",
       "tools/net462/Common7/IDE/Extensions/TestPlatform/System.Runtime.CompilerServices.Unsafe.dll": "none",
       "tools/net462/Common7/IDE/Extensions/TestPlatform/TestHostNet/Microsoft.TestPlatform.CommunicationUtilities.dll": "netframework",
@@ -190,7 +190,7 @@
       "contentFiles/any/net10.0/TestHostNetFramework/Microsoft.Win32.Primitives.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/netstandard.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.AppContext.dll": "none",
-      "contentFiles/any/net10.0/TestHostNetFramework/System.Buffers.dll": "none",
+      "contentFiles/any/net10.0/TestHostNetFramework/System.Buffers.dll": "netframework",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Collections.Concurrent.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Collections.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Collections.Immutable.dll": "netstandard",
@@ -231,7 +231,7 @@
       "contentFiles/any/net10.0/TestHostNetFramework/System.Linq.Expressions.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Linq.Parallel.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Linq.Queryable.dll": "none",
-      "contentFiles/any/net10.0/TestHostNetFramework/System.Memory.dll": "none",
+      "contentFiles/any/net10.0/TestHostNetFramework/System.Memory.dll": "netframework",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Net.Http.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Net.NameResolution.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Net.NetworkInformation.dll": "none",
@@ -243,7 +243,7 @@
       "contentFiles/any/net10.0/TestHostNetFramework/System.Net.WebHeaderCollection.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Net.WebSockets.Client.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Net.WebSockets.dll": "none",
-      "contentFiles/any/net10.0/TestHostNetFramework/System.Numerics.Vectors.dll": "none",
+      "contentFiles/any/net10.0/TestHostNetFramework/System.Numerics.Vectors.dll": "netframework",
       "contentFiles/any/net10.0/TestHostNetFramework/System.ObjectModel.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Reflection.dll": "none",
       "contentFiles/any/net10.0/TestHostNetFramework/System.Reflection.Extensions.dll": "none",
@@ -342,10 +342,10 @@
       "tools/net462/pl/Microsoft.CodeCoverage.IO.dll": "none",
       "tools/net462/pt-BR/Microsoft.CodeCoverage.IO.dll": "none",
       "tools/net462/ru/Microsoft.CodeCoverage.IO.dll": "none",
-      "tools/net462/System.Buffers.dll": "none",
+      "tools/net462/System.Buffers.dll": "netframework",
       "tools/net462/System.Collections.Immutable.dll": "netstandard",
-      "tools/net462/System.Memory.dll": "none",
-      "tools/net462/System.Numerics.Vectors.dll": "none",
+      "tools/net462/System.Memory.dll": "netframework",
+      "tools/net462/System.Numerics.Vectors.dll": "netframework",
       "tools/net462/System.Reflection.Metadata.dll": "netstandard",
       "tools/net462/System.Runtime.CompilerServices.Unsafe.dll": "none",
       "tools/net462/System.Runtime.InteropServices.RuntimeInformation.dll": "none",
@@ -451,11 +451,11 @@
       "Microsoft.VisualStudio.TestPlatform.Client.dll": "netframework",
       "Microsoft.VisualStudio.TestPlatform.Common.dll": "netframework",
       "Microsoft.VisualStudio.TestPlatform.ObjectModel.dll": "netframework",
-      "System.Buffers.dll": "none",
+      "System.Buffers.dll": "netframework",
       "System.Collections.Immutable.dll": "netstandard",
       "System.Diagnostics.DiagnosticSource.dll": "netstandard",
-      "System.Memory.dll": "none",
-      "System.Numerics.Vectors.dll": "none",
+      "System.Memory.dll": "netframework",
+      "System.Numerics.Vectors.dll": "netframework",
       "System.Reflection.Metadata.dll": "netstandard",
       "System.Runtime.CompilerServices.Unsafe.dll": "none",
       "System.Text.Json.dll": "netframework",
diff --git a/src/Microsoft.TestPlatform.CoreUtilities/Microsoft.TestPlatform.CoreUtilities.csproj b/src/Microsoft.TestPlatform.CoreUtilities/Microsoft.TestPlatform.CoreUtilities.csproj
@@ -18,6 +18,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Win32.Registry" Version="$(MicrosoftWin32RegistryVersion)" Condition="'$(TargetFramework)' == 'netstandard2.0'" />
+    <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutablePackageVersion)" Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'" />
     <PackageReference Include="System.Reflection.Metadata" Version="$(SystemReflectionMetadataVersion)" Condition="'$(TargetFrameworkIdentifier)' != '.NETCoreApp'" />
   </ItemGroup>
 
diff --git a/src/Microsoft.TestPlatform.ObjectModel/Microsoft.TestPlatform.ObjectModel.csproj b/src/Microsoft.TestPlatform.ObjectModel/Microsoft.TestPlatform.ObjectModel.csproj
@@ -35,6 +35,7 @@
   <ItemGroup>
     <!-- net48 includes tuple, we need to reference it in previous versions but only on .net framework. -->
     <PackageReference Include="System.ValueTuple" Version="4.5.0" Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net48')) != 'true' and '$(TargetFrameworkIdentifier)' == '.NETFramework'" />
+    <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutablePackageVersion)" Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'" />
     <PackageReference Include="System.Reflection.Metadata" Version="$(SystemReflectionMetadataVersion)" Condition="'$(TargetFrameworkIdentifier)' != '.NETCoreApp'" />
   </ItemGroup>
 
diff --git a/src/datacollector/app.config b/src/datacollector/app.config
@@ -22,19 +22,24 @@
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Runtime.CompilerServices.Unsafe" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
-        <bindingRedirect oldVersion="1.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
+        <bindingRedirect oldVersion="1.0.0.0-6.0.3.0" newVersion="6.0.3.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Collections.Immutable" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
-        <bindingRedirect oldVersion="1.0.0.0-9.0.0.0" newVersion="9.0.0.0" />
+        <bindingRedirect oldVersion="1.0.0.0-10.0.0.0" newVersion="10.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Reflection.Metadata" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
         <bindingRedirect oldVersion="1.0.0.0-8.0.0.0" newVersion="8.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Memory" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
-        <bindingRedirect oldVersion="0.0.0.0-4.0.1.2" newVersion="4.0.1.2" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.5.0" newVersion="4.0.5.0" />
+      </dependentAssembly>
+
+      <dependentAssembly>
+        <assemblyIdentity name="System.Buffers" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.5.0" newVersion="4.0.5.0" />
       </dependentAssembly>
     </assemblyBinding>
   </runtime>
diff --git a/src/package/Microsoft.TestPlatform.CLI/Microsoft.TestPlatform.CLI.csproj b/src/package/Microsoft.TestPlatform.CLI/Microsoft.TestPlatform.CLI.csproj
@@ -37,7 +37,7 @@
       Sometimes NU1702 is not suppressed correctly, so force reducing severity of the warning.
       See https://github.com/NuGet/Home/issues/9147
     -->
-    <MSBuildWarningsAsMessages>NU1702</MSBuildWarningsAsMessages>
+    <MSBuildWarningsAsMessages>$(MSBuildWarningsAsMessages);NU1702</MSBuildWarningsAsMessages>
   </PropertyGroup>
 
   <!-- runner and runner dependencies -->
diff --git a/src/package/Microsoft.TestPlatform.Portable/Microsoft.TestPlatform.Portable.csproj b/src/package/Microsoft.TestPlatform.Portable/Microsoft.TestPlatform.Portable.csproj
@@ -12,7 +12,7 @@
       Sometimes NU1702 is not suppressed correctly, so force reducing severity of the warning.
       See https://github.com/NuGet/Home/issues/9147
     -->
-    <MSBuildWarningsAsMessages>NU1702</MSBuildWarningsAsMessages>
+    <MSBuildWarningsAsMessages>$(MSBuildWarningsAsMessages);NU1702</MSBuildWarningsAsMessages>
   </PropertyGroup>
 
   <PropertyGroup>
diff --git a/src/package/Microsoft.TestPlatform/Microsoft.TestPlatform.csproj b/src/package/Microsoft.TestPlatform/Microsoft.TestPlatform.csproj
@@ -11,7 +11,7 @@
       Sometimes NU1702 is not suppressed correctly, so force reducing severity of the warning.
       See https://github.com/NuGet/Home/issues/9147
     -->
-    <MSBuildWarningsAsMessages>NU1702;NETSDK1023</MSBuildWarningsAsMessages>
+    <MSBuildWarningsAsMessages>$(MSBuildWarningsAsMessages);NU1702;NETSDK1023</MSBuildWarningsAsMessages>
   </PropertyGroup>
 
   <PropertyGroup>
diff --git a/src/testhost.x86/app.config b/src/testhost.x86/app.config
@@ -30,19 +30,24 @@
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Runtime.CompilerServices.Unsafe" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
-        <bindingRedirect oldVersion="1.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
+        <bindingRedirect oldVersion="1.0.0.0-6.0.3.0" newVersion="6.0.3.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Collections.Immutable" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
-        <bindingRedirect oldVersion="1.0.0.0-9.0.0.0" newVersion="9.0.0.0" />
+        <bindingRedirect oldVersion="1.0.0.0-10.0.0.0" newVersion="10.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Reflection.Metadata" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
         <bindingRedirect oldVersion="1.0.0.0-8.0.0.0" newVersion="8.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Memory" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
-        <bindingRedirect oldVersion="0.0.0.0-4.0.1.2" newVersion="4.0.1.2" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.5.0" newVersion="4.0.5.0" />
+      </dependentAssembly>
+
+      <dependentAssembly>
+        <assemblyIdentity name="System.Buffers" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.5.0" newVersion="4.0.5.0" />
       </dependentAssembly>
     </assemblyBinding>
   </runtime>
diff --git a/src/vstest.console/app.config b/src/vstest.console/app.config
@@ -22,11 +22,11 @@
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Runtime.CompilerServices.Unsafe" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
-        <bindingRedirect oldVersion="1.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
+        <bindingRedirect oldVersion="1.0.0.0-6.0.3.0" newVersion="6.0.3.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Collections.Immutable" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
-        <bindingRedirect oldVersion="1.0.0.0-9.0.0.0" newVersion="9.0.0.0" />
+        <bindingRedirect oldVersion="1.0.0.0-10.0.0.0" newVersion="10.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Reflection.Metadata" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
@@ -35,7 +35,12 @@
 
       <dependentAssembly>
         <assemblyIdentity name="System.Memory" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
-        <bindingRedirect oldVersion="0.0.0.0-4.0.1.2" newVersion="4.0.1.2" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.5.0" newVersion="4.0.5.0" />
+      </dependentAssembly>
+
+      <dependentAssembly>
+        <assemblyIdentity name="System.Buffers" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.5.0" newVersion="4.0.5.0" />
       </dependentAssembly>
 
       <dependentAssembly>
diff --git a/test/Microsoft.TestPlatform.Acceptance.IntegrationTests/DistributedTestAgentScenarioTests.cs b/test/Microsoft.TestPlatform.Acceptance.IntegrationTests/DistributedTestAgentScenarioTests.cs
@@ -0,0 +1,124 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.IO;
+
+using Microsoft.TestPlatform.TestUtilities;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace Microsoft.TestPlatform.AcceptanceTests;
+
+/// <summary>
+/// Reproduces the binding-redirect scenario experienced by Azure DevOps' Distributed
+/// Test Agent (DTAExecutionHost) and any Visual Studio host that picks up
+/// <c>Microsoft.VisualStudio.TestPlatform.Common.dll</c> without the in-box
+/// <c>vstest.console.exe.config</c> binding redirects.
+///
+/// The test loads <c>Common.dll</c> inside a net472 host that has no binding
+/// redirects in its app.config and calls
+/// <see cref="Microsoft.VisualStudio.TestPlatform.Common.Filtering.FilterExpressionWrapper"/>,
+/// which triggers <c>FastFilter.Builder</c> and forces
+/// <c>System.Collections.Immutable</c> / <c>System.Reflection.Metadata</c> to load.
+///
+/// It runs the scenario twice:
+///   1. Against the <c>Microsoft.TestPlatform</c> nupkg's
+///      <c>tools/net462/Common7/IDE/Extensions/TestPlatform/</c> layout (as DTA consumes it).
+///   2. Against the flat layout of the <c>Microsoft.VisualStudio.TestTools.TestPlatform.V2.CLI</c>
+///      VSIX (as Visual Studio consumes it).
+///
+/// Regression guard: if <c>Common.dll</c>'s compiled metadata references for SCI/SRM drift
+/// away from the versions we ship next to it, the test fails with the same
+/// <c>FileLoadException</c> customers see. Both layouts must stay self-consistent.
+/// </summary>
+[TestClass]
+public class DistributedTestAgentScenarioTests : AcceptanceTestBase
+{
+    [TestMethod]
+    [TestCategory("Windows-Review")]
+    public void LoadingCommonDllFromMicrosoftTestPlatformPackageWithoutBindingRedirectsDoesNotThrow()
+    {
+        // Nupkg layout: DTA-style consumption of the Microsoft.TestPlatform nupkg.
+        RunDtaLikeHost(toolsDirOverride: null);
+    }
+
+    [TestMethod]
+    [TestCategory("Windows-Review")]
+    public void LoadingCommonDllFromCliV2VsixLayoutWithoutBindingRedirectsDoesNotThrow()
+    {
+        // VSIX layout: flat folder with Common.dll + SCI + SRM at the root, as shipped
+        // in Microsoft.VisualStudio.TestTools.TestPlatform.V2.CLI.vsix and consumed by
+        // Visual Studio. The VSIX is unzipped into PublishDirectory by Build.cs.
+        var extractedVsixDir = Path.Combine(
+            IntegrationTestEnvironment.PublishDirectory,
+            Path.GetFileName(IntegrationTestEnvironment.LocalVsixInsertion));
+
+        Assert.IsTrue(
+            Directory.Exists(extractedVsixDir),
+            $"Extracted VSIX directory not found at '{extractedVsixDir}'. " +
+            "Build.cs is expected to unzip the V2.CLI VSIX before acceptance tests run.");
+
+        Assert.IsTrue(
+            File.Exists(Path.Combine(extractedVsixDir, "Microsoft.VisualStudio.TestPlatform.Common.dll")),
+            $"Expected Common.dll at the root of the extracted VSIX ('{extractedVsixDir}').");
+
+        RunDtaLikeHost(toolsDirOverride: extractedVsixDir);
+    }
+
+    private void RunDtaLikeHost(string? toolsDirOverride)
+    {
+        var projectPath = GetIsolatedTestAsset("DtaLikeHost.csproj", "net472");
+        var workingDir = Path.GetDirectoryName(projectPath)!;
+
+        var dotnetPath = GetPatchedDotnetPath();
+
+        var buildArgs =
+            $@"build ""{projectPath}"" -c {IntegrationTestEnvironment.BuildConfiguration} " +
+            $@"/p:PackageVersion={IntegrationTestEnvironment.LatestLocallyBuiltNugetVersion} " +
+            @"/nodeReuse:false";
+
+        if (toolsDirOverride is not null)
+        {
+            buildArgs += $@" /p:TestPlatformToolsDirOverride=""{toolsDirOverride}""";
+        }
+
+        ExecuteApplication(dotnetPath, buildArgs, out var buildOut, out var buildErr, out var buildExit, workingDirectory: workingDir);
+
+        Assert.AreEqual(
+            0,
+            buildExit,
+            $"dotnet build of DtaLikeHost failed (exit {buildExit}).\nSTDOUT:\n{buildOut}\nSTDERR:\n{buildErr}");
+
+        var exePath = Path.Combine(
+            workingDir,
+            "artifacts", "bin", "TestAssets", "DtaLikeHost",
+            IntegrationTestEnvironment.BuildConfiguration,
+            "net472",
+            "DtaLikeHost.exe");
+
+        Assert.IsTrue(File.Exists(exePath), $"Expected DtaLikeHost.exe at '{exePath}'.");
+
+        // With the fix in place, Common.dll's compiled metadata references for
+        // System.Collections.Immutable and System.Reflection.Metadata match the DLLs
+        // shipped next to it, so the host exe completes normally even without any
+        // binding redirects in its app.config.
+        ExecuteApplication(exePath, args: null, out var runOut, out var runErr, out var runExit);
+
+        Assert.AreEqual(
+            0,
+            runExit,
+            "DtaLikeHost.exe exited non-zero, which means Common.dll's compiled metadata " +
+            "references for System.Collections.Immutable / System.Reflection.Metadata do " +
+            "not match the versions shipped next to it. DTA-style hosts (no binding " +
+            "redirects) will FileLoadException on FastFilter.Builder.\n" +
+            $"Tools dir: {toolsDirOverride ?? "<nupkg default>"}\n" +
+            $"STDOUT:\n{runOut}\nSTDERR:\n{runErr}");
+
+        Assert.Contains("OK - no binding exception.", runOut);
+    }
+
+    private static string GetPatchedDotnetPath()
+    {
+        var executable = OSUtils.IsWindows ? "dotnet.exe" : "dotnet";
+        return Path.GetFullPath(Path.Combine(IntegrationTestEnvironment.RepoRootDirectory, "artifacts", "tmp", ".dotnet", executable));
+    }
+}
diff --git a/test/TestAssets/DtaLikeHost/DtaLikeHost.csproj b/test/TestAssets/DtaLikeHost/DtaLikeHost.csproj
diff --git a/test/TestAssets/DtaLikeHost/Program.cs b/test/TestAssets/DtaLikeHost/Program.cs
