Build performance concerns.

I’ve got a small project that takes 3 seconds to compile without stylecop analyzers, adding them to the project increases compilation time to 13 seconds. It’s not an issue for CI or manual(command line) build, but I definitely would not expect 400% percent longer builds in Visual Studio during development time especially taking into account that validation happens in background during file editing(incremental compilation) anyway. Is there any way to disable analyzers completely for VBCSCompiler when I build from Visual Studio? I tried the following hack, it disables analyzers for debug builds, but the build still takes 5-6 seconds instead of expected 3.

        public static void HandleCompilationStart(CompilationStartAnalysisContext context)
        {
            if (context.Options.GetType().FullName == "Microsoft.CodeAnalysis.Diagnostics.WorkspaceAnalyzerOptions" || context.Compilation.Options.OptimizationLevel == OptimizationLevel.Release)
            {
                // ...
            }
        }

Thoughts?

[sharwell]

@NikGovorov Just add the following at the end of your project file:

<Target Name="DisableAnalyzersForVisualStudioBuild"
        BeforeTargets="CoreCompile"
        Condition="'$(BuildingInsideVisualStudio)' == 'True' And '$(BuildingProject)' == 'True'">
  <!--
    Disable analyzers when building a project inside Visual Studio. Note that analyzer behavior for IntelliSense
    purposes is not altered by this.
  -->
  <ItemGroup>
    <Analyzer Remove="@(Analyzer)"/>
  </ItemGroup>
</Target>

[sharwell]

BTW. it should work this way right inside Visual Studio, maybe to be implemented on some VS update, but at least there is this workaround now.

For users who enable “warnings as errors” and users who use a rule set file to treat specific analyzer warnings as errors, which would cause building in Visual Studio to produce different results than building from the command line. This would dramatically increase the chances that developers commit code they believe works but in reality causes the automated build for their project to fail.

This issue is sufficiently important that I am quite comfortable advising people to avoid this build customization and instead focus on continually reducing the performance overhead of the StyleCop Analyzers.

That said, I’ll open a new issue to include this information somewhere in the documentation. (It’s #1711.)