Change devcontainer to use image+features

[vzarytovskii]

So we don't have to take care about updates for Debian, etc.

[baronfel]

I really like the way features make things more composable - always thought the old Dockerfile-based method, while allowing control, was too hard to keep updated!

[vzarytovskii]

Any objections against merging this? @Martin521 i know you use devcontainers a bunch.

[Martin521]

Thanks for asking. I trust you are doing the right thing, but if it can wait another day, I will try it out here.

[vzarytovskii]

Thanks for asking. I trust you are doing the right thing, but if it can wait another day, I will try it out here.

Absolutely. That'd be great if you can try and see if it still works for you, and nothing is (more) broken.

[Martin521]

Works all fine for me except that the test discovery of the Ionide test explorer fails.
It took me some time to trace it down.
The error message Couldn't build test projects. Make sure you can build projects with 'dotnet build' in the "Test Explorer" window was misleading. Looking into the sources, I found that the test discovery first calls msbuild /t:Build for the three test projects. Which led me to finding the following build output in the `Ionide msbuild" window:

[11:42:39 INFO ] [msbuild] invoking msbuild from /usr/bin/dotnet on /workspaces/fsharp3/tests/FSharp.Compiler.UnitTests/FSharp.Compiler.UnitTests.fsproj for target Build
MSBuild version 17.8.0-preview-23418-03+0125fc9fb for .NET
/usr/share/dotnet/sdk/8.0.100-rc.1.23463.5/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(266,5): error NETSDK1004: Assets file '/workspaces/fsharp3/artifacts/obj/FSharp.Compiler.UnitTests/project.assets.json' not found. Run a NuGet package restore to generate this file. [/workspaces/fsharp3/tests/FSharp.Compiler.UnitTests/FSharp.Compiler.UnitTests.fsproj::TargetFramework=net8.0]
[11:42:41 INFO ] [msbuild] invoking msbuild from /usr/bin/dotnet on /workspaces/fsharp3/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.Tests.fsproj for target Build
MSBuild version 17.8.0-preview-23418-03+0125fc9fb for .NET
/usr/share/dotnet/sdk/8.0.100-rc.1.23463.5/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(266,5): error NETSDK1004: Assets file '/workspaces/fsharp3/artifacts/obj/FSharp.Compiler.Service.Tests/project.assets.json' not found. Run a NuGet package restore to generate this file. [/workspaces/fsharp3/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.Tests.fsproj::TargetFramework=net8.0]
[11:42:44 INFO ] [msbuild] invoking msbuild from /usr/bin/dotnet on /workspaces/fsharp3/tests/FSharp.Compiler.ComponentTests/FSharp.Compiler.ComponentTests.fsproj for target Build
MSBuild version 17.8.0-preview-23418-03+0125fc9fb for .NET
  FSharp.Core -> /workspaces/fsharp3/artifacts/bin/FSharp.Core/Debug/netstandard2.0/FSharp.Core.dll
  FSharp.Compiler.Interactive.Settings -> /workspaces/fsharp3/artifacts/bin/FSharp.Compiler.Interactive.Settings/Debug/netstandard2.0/FSharp.Compiler.Interactive.Settings.dll
  FSharp.DependencyManager.Nuget -> /workspaces/fsharp3/artifacts/bin/FSharp.DependencyManager.Nuget/Debug/netstandard2.0/FSharp.DependencyManager.Nuget.dll
  FSharp.Compiler.Service -> /workspaces/fsharp3/artifacts/bin/FSharp.Compiler.Service/Debug/netstandard2.0/FSharp.Compiler.Service.dll
  FSharp.Core -> /workspaces/fsharp3/artifacts/bin/FSharp.Core/Debug/netstandard2.1/FSharp.Core.dll
  FSharp.Test.Utilities -> /workspaces/fsharp3/artifacts/bin/FSharp.Test.Utilities/Debug/net8.0/FSharp.Test.Utilities.dll
  FSharp.Compiler.ComponentTests -> /workspaces/fsharp3/artifacts/bin/FSharp.Compiler.ComponentTests/Debug/net8.0/FSharp.Compiler.ComponentTests.dll

So msbuild complains about a missing project.assets.json for UnitTests and Service.Tests, while ComponentTests build ok.

I found that setting BUILDING_USING_DOTNET=true in devcontainer.json solves the issue, but I don't know if that is the best way to do it.
Or if some setting in one of the msbuild props/proj files can solve it.
Or if Ionide test explorer should just use 'dotnet build' (but I am not sure how soon that can happen).

[vzarytovskii]

Yeah, if we set BUILDING_USING_DOTNET=true for dev container, then it will be impossible to build using build scripts. I don't know if it's possible to set this property to only dotnet commands in the test explorer.

[Martin521]

I don't know if it's possible to set this property to only dotnet commands in the test explorer.

There is no such setting.
Env seems to be the only way, and since VS Code is started from the dev container, it would need to be there.

[vzarytovskii]

I don't know if it's possible to set this property to only dotnet commands in the test explorer.

There is no such setting. Env seems to be the only way, and since VS Code is started from the dev container, it would need to be there.

It seems so, yeah. Problem is that in this case, build scripts won't work if someone needs them.

[Martin521]

Ok, then I guess you should proceed with this PR.
I will file an issue for Ionide and in the meantime use Directory.build.props.user to set BUILDING_USING_DOTNET.

[psfinaki]

/azp run

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Azure Pipelines successfully started running 2 pipeline(s).

[psfinaki]

/azp run

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Azure Pipelines successfully started running 2 pipeline(s).