Generic collection fixtures

[lonix1]

@bradwilson I didn't know whether to file this as an issue or discussion, sorry!

A generic fixture and support classes:

public class Fixture<T> : IAsyncLifetime, IDisposable {
  public Fixture() { }
  public void Dispose() { }
  public Task InitializeAsync() => Task.CompletedTask;
  public Task DisposeAsync() => Task.CompletedTask;
}


[CollectionDefinition("collection")]
public class FixtureCollection<T> : ICollectionFixture<Fixture<T>> { }


[Collection("collection")]
public abstract class TestBase<T> {
  protected TestBase(Fixture<T> fixture) => _fixture = fixture;
  protected readonly Fixture<T> _fixture;
}

I stripped down those classes to show a minimal sample (but there is "stuff" in them).

And the test class:

public class Foo { }


public class Tests : TestBase<Foo> {
  public Tests(Fixture<Foo> fixture) : base(fixture) { }
  [Fact] public void Test1() { }
  [Fact] public void Test2() { }
}

Tests fail:

The following constructor parameters did not have matching fixture data: Fixture`1 fixture

If I make this change then it works, but I can't use it as a collection fixture:

//[Collection("collection")]                                      // removed
public abstract class TestBase<T> : IClassFixture<Fixture<T>> {   // added IClassFixture

I read the docs.

Is this use case supported?

[bartelink]

ref CC of this SO question - the question in particular is related to the fact that a CollectionAttribute on a generic base class of the TestClass is not picked up (although a basic confirmation that Collection Fixtures must be concrete is also helpful as a double confirm)

[bradwilson]

The answer is: it's not a supported use case, currently. Feel free to open an issue to get it added to v3.

[lonix1]

Thanks - I used the "Create issue from discussion" feature. Issue #2557.