Directory.Build.targets

<Project>
  <Target Name="ValidateAnalyzerProjectIsolation" BeforeTargets="ResolveReferences" Condition="'$(IsAnalyzerProject)' == 'true'">
    <Error Condition="'$(TargetFramework)' != 'netstandard2.0'" Text="$(MSBuildProjectName) must target netstandard2.0 so the analyzer can run in broad Roslyn hosts." />
    <Error Condition="'@(ProjectReference)' != ''" Text="$(MSBuildProjectName) must not use ProjectReference. Port required logic into analyzer/ with characterization tests instead." />
  </Target>
</Project>