Switch From PCLs to .NET Standard

Summary

Microsoft has officially deprecated Portable Class Libraries, which is what Duality is based on with regard to portability. Projects still compile just fine and will for the foreseeable future, but it will get progressively harder and less intuitive to keep things working and expanding on it. Consider switching all PCL projects to .NET Standard for v3.0.

Analysis

• Duality PCLs use Profile111, which is equivalent to .NET Standard 1.1. Use this standard version for maximum compatibility.
  • Check which VS version is minimum required to create and build .NET Standard 1.1 libraries using the new reduced csproj format. Don’t use the .json format, seems pretty much deprecated by now.
  • Be careful how NuGet packages are referenced. The csproj PackageReference item is not supported for all project types yet, see here. Might be better to stick to packages.config for now.
  • Consider doing a full switch to VS 2017 and the new project system as part of this change.
• .NET Standard packages require at least NuGet 2.12 or 3.4, so the Duality package manager will need to be updated to this first. The new csproj package reference format requires at least NuGet 4.0.
  • It may also need to handle platform-dependent dependency scenarios.
  • Make sure that Duality packages continue to be able to reference regular NuGet packages.
• Figure out how the NuGet package specs for Duality packages need to be changed in order in order to properly identify as netstandard packages.
• Get proficient with how .NET Standard works combined with regular .NET Framework applications and libraries when it comes to dependencies and runtime behavior.
  • Make sure the editor doesn’t get spammed with .NET Framework specific forward-only assemblies.
  • Make sure the deployed launcher still works on platforms it worked before, like Linux and MacOS via Mono.
  • What’s the role of reference assemblies in this?
• Some links for further research:
  • https://stackoverflow.com/questions/42254288/referencing-a-net-standard-library-from-a-windows-class-library
  • https://stackoverflow.com/questions/44617898/how-do-you-reference-a-net-standard-library-from-a-net-framework-4-5-console-a
  • https://github.com/dotnet/standard/issues/410
  • https://github.com/dotnet/standard/issues/481
  • https://www.hanselman.com/blog/ReferencingNETStandardAssembliesFromBothNETCoreAndNETFramework.aspx
  • https://github.com/dotnet/standard/issues/146#issuecomment-271105398
  • https://docs.microsoft.com/en-us/nuget/guides/create-net-standard-packages-vs2017
  • https://docs.microsoft.com/en-us/nuget/guides/create-net-standard-packages-vs2015
• Projects to switch:
  • FarseerDuality
  • NVorbis
  • Duality / Core
  • Primitives
  • Compatibility
  • Tilemaps (core and sample)
  • All sample projects
  • The game plugin template
• Note that it might also be required to change the AppVeyor CI settings to run in a new environment. Check the current settings to see which VS version is used.

[ilexp]

Some MS docs on multi-targeting platforms with .NET Standard: https://docs.microsoft.com/en-us/dotnet/standard/library-guidance/cross-platform-targeting

One point to note is that they explicitly recommend not targeting any 1.x standard version unless there is a specific older platform that would otherwise be unsupported. Might be worth it to reconsider the 1.x target after verifying exactly which platforms and potential future platforms would be affected.

[Barsonax]

Fix the broken Canvas rendering unit test that was mentioned in the chat after recent updates to the netstandard feature branch.

This was broken while attempting to migrate to the new csproj format to clean up the nuget packages and make that more consistent. I decided to do it since all the plugin projects are already migrated now. Its not strictly neccessary. Since it turned out to be more complex than anticipated it might be better to do this later (and create a separate issue about it).

Made a issue for this: https://github.com/AdamsLair/duality/issues/737 We should tackle that issue after we complete this one.