How to migrate xUnit fixtures?

[Xzelsius]

Let's say I have something like this

public sealed class AzuriteInfrastructure : IAsyncLifetime
{
    private readonly AzuriteContainer container;

    public AzuriteInfrastructure()
    {
        try
        {
            this.container = new AzuriteBuilder()
                .WithCleanUp(true)
                .Build();
        }
        catch
        {
            throw new TestClassException("Failed to create Azurite test container definition");
        }
    }

    public Task InitializeAsync()
    {
        return this.container.StartAsync();
    }

    public async Task DisposeAsync()
    {
        await this.container.StopAsync();
        await this.container.DisposeAsync();
    }
}

[CollectionDefinition(Name)]
public class ApiTestCollection : ICollectionFixture<AzuriteInfrastructure>
{
    public const string Name = nameof(ApiTestCollection);
}

public abstract class ApiTest(AzuriteInfrastructure azurite) : IAsyncLifetime
{
    //....
}

[TestCollection(ApiTestCollection.Name)]
public sealed MyTestClass(AzuriteInfrastructure azurite) : ApiTest(azurite)
{
    [Fact]
    public async Task Does_assert_something()
    {
        //... uses the Azurite container
    }
}

Above code does spin up an Azurite container (using Testcontainers) once per test collection.
It calls InitializeAsync() before executing a test.
All tests then get this instance injected and can do whatever they want with it.
Once all tests of that collection were executed the DisposeAsync() of AzuriteInfrastructure is called.

How would you do this in TUnit?
I actually find TUnit pretty interesting and would love to use it, but I wasn't able to properly do above thing, which I heavily use in my code bases.

Note: Since xUnit 2.x does not support assembly fixtures, I basically have all tests in a custom test collection with that ICollectionFixture<T>. So my question is mainly for fixtures that are the same for the entire assembly. But if you can explain different fixture types, I would appreciate it.

[Xzelsius]

By searching the docs again I found https://thomhurst.github.io/TUnit/docs/comparison/framework-differences#assembly-level-hooks
Is this the way to go?

[thomhurst]

You could do this:

public static class AzuriteInfrastructure
{
    public static AzuriteContainer Container { get; private set; }

    [Before(Assembly)]
    public static async Task Setup()
    {
        try
        {
            Container = new AzuriteBuilder()
                .WithCleanUp(true)
                .Build();

            await Container.StartAsync();
        }
        catch
        {
            throw new TestClassException("Failed to create Azurite test container definition");
        }
    }

    [After(Assembly)]
    public static async Task TearDown()
    {
        await Container.StopAsync();
        await Container.DisposeAsync();
    }
}

public abstract class ApiTest
{
    public AzuriteContainer Container => AzuriteInfrastructure.Container;
}

public sealed class MyTestClass : ApiTest
{
    [Fact]
    public async Task Does_assert_something()
    {
        //... uses the Azurite container
    }
}

[thomhurst]

Or this:

public sealed class AzuriteInfrastructure : IAsyncInitializer, IAsyncDisposable
{
    private readonly AzuriteContainer container;

    public AzuriteInfrastructure()
    {
        try
        {
            this.container = new AzuriteBuilder()
                .WithCleanUp(true)
                .Build();
        }
        catch
        {
            throw new TestClassException("Failed to create Azurite test container definition");
        }
    }

    public Task InitializeAsync()
    {
        return this.container.StartAsync();
    }

    public async ValueTask DisposeAsync()
    {
        await this.container.StopAsync();
        await this.container.DisposeAsync();
    }
}

[ClassDataSource<AzuriteInfrastructure>(Shared = SharedType.Globally)]
public sealed class MyTestClass(AzuriteInfrastructure azurite) : ApiTest(azurite)
{
    [Test]
    public async Task Does_assert_something()
    {
        //... uses the Azurite container
    }
}

[Xzelsius]

@thomhurst Thanks for that quick answer! That seems pretty straight forward :)