Enable trim and AOT analyzers for selected library tests

[Copilot]

Description

Several library test projects suppressed trim/AOT analyzer warnings by disabling the analyzers at the project level. This change enables the analyzers for the selected test projects where appropriate and replaces broad suppressions with targeted fixes or narrow warning pragmas at known test-only reflection and dynamic-code sites.

• Removed the dotnet/runtime#126862 analyzer-disable blocks from the selected test projects, while leaving Microsoft.Extensions.HostFactoryResolver.Tests disabled for separate follow-up because enabling it would require product changes.
• Replaced avoidable warnings with analyzer-friendly code, such as DiagnosticMethodInfo, Enum.GetValues<TEnum>(), LINQ-based collection conversion, and source-project references where applicable.
• Added .NET Framework-compatible fallbacks or source-linked attributes where analyzer-friendly APIs and annotations are unavailable in net481 test builds.
• Updated System.Threading.RateLimiting.Tests to reference the source project with SkipUseReferenceAssembly="true" and avoid local reflection suppressions.
• Marked reflection-heavy test helpers with trim annotations where appropriate, including source generator structural equality helpers and QUIC interop reset helpers.
• Propagated required DynamicallyAccessedMembers annotations through the WinHttpHandler test marshal shim.
• Kept GetStateMachineData.Describe and Watchdog behavior intact, with narrow suppressions documenting that the diagnostic reflection path is dead code after runtime async.
• Added narrow #pragma warning disable/restore scopes only for remaining emitted IL warnings that require reflection, dynamic code, or unsupported trim/AOT analysis patterns.
• Added explanatory context to remaining targeted suppressions, including issue links or rationale for why the test-only operation is safe.

[dotnet-policy-service]

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[MichalStrehovsky]

@copilot

[MichalStrehovsky]

@copilot

[MichalStrehovsky]

@copilot build breaks

D:\a\_work\1\s\src\libraries\System.Management\tests\System\Management\ManagementObjectTests.cs(118,17): error IL2026: Using member 'System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream, Object)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. BinaryFormatter serialization is not trim compatible because the type of objects being processed cannot be statically discovered. [D:\a\_work\1\s\src\libraries\System.Management\tests\System.Management.Tests.csproj::TargetFramework=net11.0-windows]
D:\a\_work\1\s\src\libraries\System.Management\tests\System\Management\ManagementObjectTests.cs(121,54): error IL2026: Using member 'System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. BinaryFormatter serialization is not trim compatible because the type of objects being processed cannot be statically discovered. [D:\a\_work\1\s\src\libraries\System.Management\tests\System.Management.Tests.csproj::TargetFramework=net11.0-windows]
D:\a\_work\1\s\src\libraries\System.Management\tests\System\Management\ManagementObjectTests.cs(121,54): error IL3050: Using member 'System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream)' which has 'RequiresDynamicCodeAttribute' can break functionality when AOT compiling. BinaryFormatter serialization uses dynamic code generation, the type of objects being processed cannot be statically discovered. [D:\a\_work\1\s\src\libraries\System.Management\tests\System.Management.Tests.csproj::TargetFramework=net11.0-windows]
D:\a\_work\1\s\src\libraries\System.DirectoryServices\tests\System\DirectoryServices\DirectoryServicesTests.cs(21,31): error IL2026: Using member 'System.Reflection.Assembly.GetTypes()' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed. [D:\a\_work\1\s\src\libraries\System.DirectoryServices\tests\System.DirectoryServices.Tests.csproj::TargetFramework=net11.0-windows]

For the ManagementObjectTests.cs occurence, mark the method as [RequiresUnreferencedCode("Binary formatter")]

For the DirectoryServicesTests.cs, suppress the warning using #pragma. Add a comment saying "The purpose of the test is to load all types in the assembly. All types that are left is also fine.".

[Copilot]

@copilot build breaks

...

Fixed in fa2c19f by adding targeted annotations/suppressions for the reported System.Management and System.DirectoryServices analyzer breaks. I verified the affected test projects build and run via /t:test with 0 warnings and 0 errors.

[MichalStrehovsky]

Build breaks in the .NET framework build (TargetFramework=net481).

2026-05-21T08:19:22.2874157Z D:\a\_work\1\s\src\libraries\Microsoft.Extensions.DependencyInjection\tests\DI.External.Tests\SkippableDependencyInjectionSpecificationTests.cs(19,43): error CS0103: The name 'DiagnosticMethodInfo' does not exist in the current context [D:\a\_work\1\s\src\libraries\Microsoft.Extensions.DependencyInjection\tests\DI.External.Tests\Microsoft.Extensions.DependencyInjection.ExternalContainers.Tests.csproj::TargetFramework=net481]
2026-05-21T08:19:22.2875350Z D:\a\_work\1\s\src\libraries\Common\tests\SourceGenerators\GeneratorTestHelpers.cs(19,10): error CS0122: 'RequiresUnreferencedCodeAttribute' is inaccessible due to its protection level [D:\a\_work\1\s\src\libraries\Microsoft.Extensions.Configuration.Binder\tests\SourceGenerationTests\Microsoft.Extensions.Configuration.Binder.SourceGeneration.Tests.csproj::TargetFramework=net481]
2026-05-21T08:19:22.2890994Z D:\a\_work\1\s\src\libraries\Common\tests\SourceGenerators\GeneratorTestHelpers.cs(19,10): error CS0122: 'RequiresUnreferencedCodeAttribute' is inaccessible due to its protection level [D:\a\_work\1\s\src\libraries\System.Text.Json\tests\System.Text.Json.SourceGeneration.Unit.Tests\System.Text.Json.SourceGeneration.Roslyn3.11.Unit.Tests.csproj::TargetFramework=net481]
2026-05-21T08:19:22.2892327Z D:\a\_work\1\s\src\libraries\Common\tests\SourceGenerators\GeneratorTestHelpers.cs(19,10): error CS0122: 'RequiresUnreferencedCodeAttribute' is inaccessible due to its protection level [D:\a\_work\1\s\src\libraries\System.Text.Json\tests\System.Text.Json.SourceGeneration.Unit.Tests\System.Text.Json.SourceGeneration.Roslyn4.4.Unit.Tests.csproj::TargetFramework=net481]

Add ifdef for the DiagnosticMethodInfo, include the .cs file with the RequiresUnreferencedCodeAttribute attribute in the test project for the other one.

Also a build break on Windows x64:

src\libraries\System.Net.Http.WinHttpHandler\tests\UnitTests\FakeMarshal.cs(57,20): error IL2091: (NETCORE_ENGINEERING_TELEMETRY=Build) 'T' generic argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicConstructors', 'DynamicallyAccessedMemberTypes.NonPublicConstructors' in 'System.Runtime.InteropServices.Marshal.PtrToStructure<T>(nint)'. The generic parameter 'T' of 'System.Net.Http.Marshal.PtrToStructure<T>(nint)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.

For this, propagate the DynamicallyAccessedMembers annotations from the called method to the calling methods T.

@copilot

[Copilot]

Build breaks in the .NET framework build (TargetFramework=net481).

...

Fixed in ea6ff58. I added the net481 fallback around DiagnosticMethodInfo, linked the shared RequiresUnreferencedCodeAttribute source into the source-generator test projects for .NET Framework, and propagated the PtrToStructure<T> DAM annotations in the WinHttpHandler test fake. Targeted builds now pass; WinHttpHandler /t:test also passed.

[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• badhost
  • Triggering command: /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet exec --runtimeconfig System.Net.Http.Functional.Tests.runtimeconfig.json --depsfile System.Net.Http.Functional.Tests.deps.json /home/REDACTED/.nuget/packages/microsoft.dotnet.xunitconsoleREDACTED/2.9.3-beta.26257.113/build/../tools/net/xunit.console.dll System.Net.Http.Functional.Tests.dll -xml testResults.xml -nologo -notrait category=OuterLoop -notrait category=failing 8 d-value d-variable j/native/net11.0[:upper:] 8 (dns block)
• does.not.exist.sorry
  • Triggering command: /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet exec --runtimeconfig /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/System.Net.Http.Functional.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/System.Net.Http.Functional.Tests.deps.json /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/Microsoft.DotNet.RemoteExecutor.dll System.Net.Http.Functional.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51 System.Net.Http.Functional.Tests.DiagnosticsTest <SendAsync_ConnectionFailure_RecordsActivitiesWithCorrectErrorInfo>g__RunTest|18_0 /tmp/ufcs1dmo.x5h 1.1 False dns -DNDEBUG inja -DHOST_UNIX -DNDgit -MD -MT j/native/net11.0HEAD (dns block)
  • Triggering command: /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet exec --runtimeconfig /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/System.Net.Http.Functional.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/System.Net.Http.Functional.Tests.deps.json /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/Microsoft.DotNet.RemoteExecutor.dll System.Net.Http.Functional.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51 System.Net.Http.Functional.Tests.DiagnosticsTest <SendAsync_ConnectionFailure_RecordsActivitiesWithCorrectErrorInfo>g__RunTest|18_0 /tmp/mwl3z5m1.1kj 1.1 True dns -DNDEBUG 18 IBUTE_ALIGNED -Dbash d-variable in-requires-head--runtime-path GET_LINUX -DTARG/home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x/home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/Microsoft.DotNet.RemoteExecutor.dll (dns block)
  • Triggering command: /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet exec --runtimeconfig /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/System.Net.Http.Functional.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/System.Net.Http.Functional.Tests.deps.json /home/REDACTED/work/runtime/runtime/artifacts/bin/System.Net.Http.Functional.Tests/Release/net11.0-linux/Microsoft.DotNet.RemoteExecutor.dll System.Net.Http.Functional.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51 System.Net.Http.Functional.Tests.DiagnosticsTest <SendAsync_ConnectionFailure_RecordsActivitiesWithCorrectErrorInfo>g__RunTest|18_0 /tmp/mbnhq2lj.bmd 2.0 True dns (dns block)
• www.some.example
  • Triggering command: /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet /home/REDACTED/work/runtime/runtime/artifacts/bin/testhost/net11.0-linux-Release-x64/dotnet exec --runtimeconfig System.Net.Http.Functional.Tests.runtimeconfig.json --depsfile System.Net.Http.Functional.Tests.deps.json /home/REDACTED/.nuget/packages/microsoft.dotnet.xunitconsoleREDACTED/2.9.3-beta.26257.113/build/../tools/net/xunit.console.dll System.Net.Http.Functional.Tests.dll -xml testResults.xml -nologo -notrait category=OuterLoop -notrait category=failing 8 d-value d-variable j/native/net11.0[:upper:] 8 (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

[sbomer]

One question, otherwise LGTM, thanks!