How can I disable transitive .NET analyzers from a NuGet dependency?

The behavior you’re seeing is expected when analyzers are brought in transitively. The ExcludeAssets flag on your PackageReference will prevent analyzers from your direct package reference—but it does not “climb in” and remove analyzer assets that are brought in by your dependency’s own package references.

In your case, LibraryWithAnalyzers (or one of its dependencies) is referencing its analyzers without marking them as private. As a result, they become transitive assets in your project even though you’ve set ExcludeAssets on your direct reference.

Options to Prevent Analyzer Execution

1. Disable Analyzers Globally:
   If you want to disable all analyzers for your project, you can set the MSBuild property to prevent them from running at build time. For example, in your project file (.csproj):

   XMLCopied
   <PropertyGroup>
     <RunAnalyzersDuringBuild>false</RunAnalyzersDuringBuild>
   </PropertyGroup>

   This will disable all analyzer execution during both design-time and build-time.

2. Suppress or Remove Specific Analyzers:
   If you want to keep analyzers in your project (for potential future use) but disable the problematic ones, you may either:

   • Suppress individual rules in your .editorconfig, or
   • Use the <NoWarn> property to mute the warnings.

   This approach gives you selective control while still keeping the analyzers as part of the build.

3. Repackage or Adjust the Dependency (if possible):
   If you have control over the LibraryWithAnalyzers package, you can update it so that its analyzer assets are marked as private assets. For instance, when referencing the analyzers inside that project, they can be declared with:

   XMLCopied
   <PackageReference Include="StyleCop.Analyzers" Version="*" PrivateAssets="all" />

   This ensures that the analyzer assets do not flow transitively to consumers of the package.

Summary

There’s nothing “wrong” with your project configuration; the issue is that ExcludeAssets does not affect transitive dependencies. Your options are to disable analyzers outright using a project property, suppress the warnings from analyzers via .editorconfig/NoWarn, or adjust the package that is shipping the analyzers so that they aren’t transitively exposed.

Choose the approach that best fits your project’s needs.