bring Microsoft.DotNet.AsmDiff to nuget.org

[bitbonk]

Microsoft.DotNet.AsmDiff is a very helpful tool and is widely used in our (DocFX based) documentation for the frameworks and libraries that we offer.

Unfortunately it is just a (somewhat hidden) Microsoft internal tool, only available on an internal feed containing lots of nightly builds. The versioning scheme of the package and the changes made in each version are also not clear. It would be really cool if you would convert it to a public tool on nuget.org and make it more widely known and used throughout the .NET ecosystem.

It would be cool if more open source nuget package authors would embrace such a tool and offer a page that documents public API changes in their documentation.

[ViktorHofer]

Publicly releasing the current Microsoft.DotNet.AsmDiff tool isn't planned as the tool still relies on Microsoft.Cci which we want to get rid off as it isn't maintained anymore. Instead we want to move this tool into dotnet/sdk, next to APICompat and GenAPI. We could eventually release it from there.

Note that these are aspirational goals and in no way committed for .NET 9. This might be a long term improvement over the next years.

Meanwhile you will need to continue to consume it from our "internal" dotnet-eng feed without any clear indication of what changes in a given version. Note that we aren't planning to change this tool at all, so if you see new versions it's highly likely that nothing has changed.

[ViktorHofer]

cc @ericstj @carlossanlop

[carlossanlop]

@bitbonk thanks for sharing this information. I am surprised, yet pleased, that there is someone else using it. The .NET team uses it to publish the list of new APIs from one version to another.

I'll let my team know about this and will have a conversation with them about the future plans for this tool.

[bitbonk]

FYI: In addition to generating documentation for our customers, we also started using this tool in CI to generate a report about what changed in a PR/branch to make the review of the public API easier.
We previously tried Microsoft.CodeAnalysis.PublicApiAnalyzers which didn't really work well and we now instead settled with this simple reporting solution.