Fix MA0182 false positive on types with DynamicallyAccessedMembers attribute

[Copilot]

MA0182 incorrectly flags internal types as unused when marked with [DynamicallyAccessedMembers], which indicates the type is accessed via reflection.

Changes

• Analyzer: Added check in IsPotentialUnusedType to exclude types with DynamicallyAccessedMembersAttribute

  • Store attribute type reference in AnalyzerContext constructor from compilation
  • Pass attribute to validation method for filtering

• Tests: Added coverage for internal classes, private nested classes, and structs with the attribute

Example

// Previously flagged as unused, now correctly ignored
[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
internal sealed class FakeTaskHandler : ITaskHandler
{
    // Accessed via reflection at runtime
}

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:

• www.nuget.org
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/Meziantou.Analyzer/Meziantou.Analyzer/tests/Meziantou.Analyzer.Test/bin/Debug/net10.0/Meziantou.Analyzer.Test.runtimeconfig.json --depsfile /home/REDACTED/work/Meziantou.Analyzer/Meziantou.Analyzer/tests/Meziantou.Analyzer.Test/bin/Debug/net10.0/Meziantou.Analyzer.Test.deps.json /home/REDACTED/work/Meziantou.Analyzer/Meziantou.Analyzer/tests/Meziantou.Analyzer.Test/bin/Debug/net10.0/testhost.dll --port 46883 --endpoint 127.0.0.1:046883 --role client --parentprocessid 4373 --datacollectionport 36869 --telemetryoptedin false (dns block)
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/Meziantou.Analyzer/Meziantou.Analyzer/tests/Meziantou.Analyzer.Test/bin/Debug/net10.0/Meziantou.Analyzer.Test.runtimeconfig.json --depsfile /home/REDACTED/work/Meziantou.Analyzer/Meziantou.Analyzer/tests/Meziantou.Analyzer.Test/bin/Debug/net10.0/Meziantou.Analyzer.Test.deps.json /home/REDACTED/work/Meziantou.Analyzer/Meziantou.Analyzer/tests/Meziantou.Analyzer.Test/bin/Debug/net10.0/testhost.dll --port 45901 --endpoint 127.0.0.1:045901 --role client --parentprocessid 4552 --datacollectionport 41269 --telemetryoptedin false (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)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>MA0182 false positive on [DynamicallyAccessedMembers]</issue_title>
<issue_description>### Version of the Meziantou.Analyzer NuGet package

2.0.275

Rule Identifier

MA0182

Target Framework

net10.0

C# Language version

C# 12

Description

MA0182 report the follow error

21>LocalTaskHandlerTypeUnitTests.cs(31,23): Error MA0182 : Internal type 'FakeTaskHandler1' is apparently never used. If so, remove it from the assembly. If this type is intended to contain only static members, make it 'static'. (https://github.com/meziantou/Meziantou.Analyzer/blob/main/docs/Rules/MA0182.md)

but it marked with DynamicallyAccessedMembers attribute

	[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
	private sealed class FakeTaskHandler1 : ITaskHandler

According to docs

Indicates that certain members on a specified Type are accessed dynamically, for example, through Reflection.

Reproduction Steps

Unfortunately, I can't reproduce the issue on a sample project

Other information

No response</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes MA0182 false positive on [DynamicallyAccessedMembers] #962

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