Add support for additional TFM's

[mchylek]

Add support for .netstandard2.0 and net5.0

Related to mbraceproject/FsPickler#123

[dsyme]

Great!

[eiriktsarpalis]

The library intentionally doesn't target netstandard (since .NET framework is no longer supported). What would be the benefit of targeting net5.0? Isn't netcoreapp3.1 sufficient and compatible with new releases?

[mchylek]

Hi @eiriktsarpalis, actually the main driver for this PR is to bring back support for .Net Framework (required for project I'm working on). Regarding TFM's I'm happy to remove explicit target for net5.0 - I was under impression it's recommended to use both netcoreapp* and net5.0+.

[eiriktsarpalis]

Feel free to try, but as mentioned support was removed intentionally (can't recall the precise reason but I believe it might have something to do with AppDomains and assembly loading semantics). Have you verified that tests are passing for netfx? Seems to be failing in CI.

[mchylek]

For netfx I had to polyfill AssemblyLoadContext with single AppDomain that was enough to make tests passing (also works fine in my internal project) but I'm aware of it's limitations.

CI is failing currently on netcoreapp3.1 tests (looks like ThunkServer didn't start)

[eiriktsarpalis]

According to the CI logs only net5.0, net6.0 and netcoreapp3.1 are being tested, but no netfx targets. I'd argue that only one Core runtime is needed in testing (the latest, net6.0 should suffice).

[mchylek]

NetFx tests are also executed https://ci.appveyor.com/project/dsyme/vagabond/builds/42827493#L384

Passed!  - Failed:     0, Passed:    56, Skipped:     1, Total:    57, Duration: 49 s - Vagabond.Tests.dll (net472)

Just to confirm - nuget packages should target netcoreapp3.1 + netstandard2.0, and test should be executed on latest runtime (net6.0) and netfx (net472)?

Also CI currently fails on generating docs. I've tried to update FSharp.Formatting but looks like Razor support was dropped. Any recommendations? 😊

C:\projects\vagabond> "dotnet.exe"  fsi --define:RELEASE docs/tools/generate.fsx (In: false, Out: false, Err: false)
error FS0193: internal error: Could not load type 'range' from assembly 'FSharp.Compiler.Service, Version=41.0.2.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

[eiriktsarpalis]

Just to confirm - nuget packages should target netcoreapp3.1 + netstandard2.0, and test should be executed on latest runtime (net6.0) and netfx (net472)?

Yes please 👍

Also CI currently fails on generating docs. I've tried to update FSharp.Formatting but looks like Razor support was dropped. Any recommendations? 😊

No recommendations unfortunately. Have you tried updating to the latest version of FSharp.Formatting?

[mchylek]

For FSharp.Formatting 14.0.1 (latest) it just failing with

generate.fsx(12,24): error FS0039: The namespace 'Razor' is not defined.

And FSharp.Formatting.Razor 4.1.0 is returning the original error

error FS0193: internal error: Could not load type 'range' from assembly 'FSharp.Compiler.Service, Version=41.0.2.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

Alternatively I wonder if there is a switch to run fsi from older sdk (3.1)

[eiriktsarpalis]

I think it boils down to updating the local generate.fsx so that it works with the latest FSharp.Formatting. That might include removing deprecated namespaces.

[mchylek]

Are you fine with migrating docs generation to fsdocs?

[eiriktsarpalis]

Sure, whatever is bleeding edge I approve of.

[dsyme]

Yes just move to latest fsdocs-tool (though it requires net5.0 to run, we must fix that)

[mchylek]

Unfortunately I had problems with migrating to fsdocs-tool as it didn't work with net6.0, and when switching to net5.0 I've observed issues with FAKE.

CI is green now as I've made workaround to use SDK 3.1 purely for docs generation. I'm happy to migrate to fsdocs (separate PR) once issue with net6.0 will be resolved.

[eiriktsarpalis]

Thanks!