Where do builds set the AssemblyCompanyAttribute attribute for assemblies?

Discussed in https://github.com/dotnet/source-build/discussions/3134

<div type='discussions-op-text'>

^{Originally posted by jcolebrand November 29, 2022} Where do builds set the AssemblyCompanyAttribute attribute for assemblies?

Apologies if this is the wrong place, feel free to redirect me to a better place to ask, but seems like the source-build team knows these things better than anyone, if I had to guess.

We are looking to build some tooling around assembly scanning and wanted to exclude the Microsoft assemblies from our internal assemblies (not excluding everyone’s assemblies, just the ones owned by the Microsoft teams) and wanted to know if there was a likelihood that the AssemblyCompanyAttribute attribute may change in the future. With quite a few thousand (mostly tests and handling code) results in github seearch, and knowing that it is usually just AssemblyCompany in expected files, I’m not sure how to narrow it down to see where it might get injected into a build pipeline.

“But Cole, why would it ever change from Microsoft” excellent question. While I can ponder a few ideas, such as a Community Foundation type naming structure, I don’t know exactly, but figured if I can find who owns that, they can give me a better indication of if it might ever change.

FWIW this is the code my coworker wrote today:

        private static bool IsMicrosoftAssembly(AssemblyDefinition assembly)
        {
            if (assembly.HasCustomAttributes)
            {
                var assemblyCompany = assembly.CustomAttributes.FirstOrDefault(a => a.AttributeType.FullName == "System.Reflection.AssemblyCompanyAttribute");

                return ((assemblyCompany != null)
                    && assemblyCompany.ConstructorArguments.Any(arg => arg.Value?.ToString().StartsWith("Microsoft") == true));
            }

            return false;
        }

I’m sure you can see how that would potentially be a problem, especially if we don’t understand the nuances, etc. Is it brittle? Almost certainly.

I would also accept “look, don’t do that, do this instead” but better to learn how to fish with seeing the entirety of the ecosystem than to ask highly specific questions, because I would like to learn how to fish.

If it were me setting this up, I would have that as a variable in a pipeline and not hard-coded in a script, which are dynamic, and so I expect it is here as well.

Cheers!</div>

[jcolebrand]

@riarenas I agree, but sometimes people have floated ideas in the past and someone knows a thing or two, ya know?

@crummel I agree that’s annoying.

Thanks all for the answers. As always, y’all are amazing and I am a very grateful pipeline consuming dev. I appreciate all the work y’all and your teams put into keeping this thing going strong!

[michellemcdaniel]

Closing this as it seems the questions were answered