Environment sdk version restriction negatively affects dotnet tools

[Lanayx]

Here are the links to the main sympthoms
MessagePack-CSharp/MessagePack-CSharp#1387
fsprojects/FSharpLint#536

The root of the issue seems to be these lines:

            // Components of the SDK often have dependencies on the runtime they shipped with, including that several tasks that shipped
            // in the .NET 5 SDK rely on the .NET 5.0 runtime. Assuming the runtime that shipped with a particular SDK has the same version,
            // this ensures that we don't choose an SDK that doesn't work with the runtime of the chosen application. This is not guaranteed
            // to always work but should work for now.
            if (major > Environment.Version.Major ||
                (major == Environment.Version.Major && minor > Environment.Version.Minor))
            {
                return null;
            }

So if library is built with .net5.0 and then used on the environment with just .net6.0 is installed it fails, because the check above returns null. At the same time there shouldn't be any restrictions of running tools on higher versions of sdk's.

[JoeRobich]

I think enabling rollForward would be the best option for these tools. They could continue to target net5.0 if they wish, but the runtime could roll up to 6.0, which would be compatible with .NET 6 SDKs. See documentation at https://docs.microsoft.com/en-us/dotnet/core/project-sdk/msbuild-props#rollforward

[baronfel]

One thing I discovered with Ionide is that when an app targets net5.0 and is rolled forward to a newer runtime, the System.Environment.Version values don't seem to update to those of the runtime. This killed my ability to use this library entirely, since a thte time we targeted net5.0 for reach and enabled roll-forward as you describe.

[jzabroski]

One thing I discovered with Ionide is that when an app targets net5.0 and is rolled forward to a newer runtime, the System.Environment.Version values don't seem to update to those of the runtime.

If true, please file a bug in dotnet/runtime. That sounds very incorrect.

[rainersigwald]

One thing I discovered with Ionide is that when an app targets net5.0 and is rolled forward to a newer runtime, the System.Environment.Version values don't seem to update to those of the runtime.

I'm not seeing this.

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
    <RollForward>LatestMajor</RollForward>
  </PropertyGroup>

</Project>

using System;                                                                                                                                                                                                                                   namespace Net5Rollforward
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(System.Environment.Version);
        }
    }
}

S:\play\Net5Rollforward via .NET v7.0.100-preview.5.22307.18 🎯 net5.0
❯ dotnet run
7.0.0

[baronfel]

Well that's very interesting. I can't find my notes from the tire fire that was this pr, but a finding like that is what led me to rip it all out. Perhaps its time for a more measured look again.

[YuliiaKovalova]

It has been recently addressed in scope of this ticket.
#271

[Lanayx]

@YuliiaKovalova can you please link the PR or commit to see how that was fixed? I don't see any PR in the issue you mentioned

[JoeRobich]

@Lanayx I believe these are the PRs #265 & #281

[YuliiaKovalova]

Hi @Lanayx and @JoeRobich ,

You can test the changes in the scope of the recently released package:
https://www.nuget.org/packages/Microsoft.Build.Locator/1.7.8

Please let us know if you have any questions/concerns.