1.2.0 causes NUnit.Engine.TestEngineActivator.CreateInstance() to return null

[dave-yotta]

#! "netcoreapp3.1"
#r "nuget: NUnit.Engine, 3.10.0"
using NUnit.Engine;
var engine = TestEngineActivator.CreateInstance();

since 1.2.0 TestEngineActivator.CreateInstance is returning null.
Something to do with assembly changes?

[seesharper]

@hrumhurum We have an issue here. Might be related to the fact that the code does Assembly.LoadFrom

https://github.com/nunit/nunit-console/blob/master/src/NUnitEngine/nunit.engine.api/TestEngineActivator.cs

[hrumhurum]

Assembly.LoadFrom is not routed to AssemblyLoadContext.CurrentContextualReflectionContext, while Assembly.Load is routed correctly. This looks like an omission in .NET runtime.

Due to that flaw, the assemblies loaded with Assembly.LoadFrom are always loaded to the default AssemblyLoadContext.

There are three possible workarounds:

1. Do not use assembly isolation at all at dotnet-script level, or
2. Keep a handcrafted list of affected assemblies and homogenize them with the default assembly load context
3. Contact NUnit and propose to use AssemblyLoadContext.CurrentContextualReflectionContext for assembly loading when it is not null

What shall we choose?

[seesharper]

Me and @filipw discussed this and we landed on making this an opt-in feature for now.

Number 2 and 3 are not the best options as we would most probably run into other libraries with the same "defect" and the list will just grow

@filipw What would be a good name for such an option? -ilc | --isolated-load-context ?

[dave-yotta]

Quick reaction there guys :)

[filipw]

1.2.1 is out which makes the isolation opt in based on an --isolated-load-context switch

I think this can be closed