Async support for hooks is broken because of incorrect code in HookMetadataGenerator

[DavidZidar]

Hi,

I updated to the latest TUnit version 0.56.5 and now my async [Before(Test)] hooks aren't working properly because they are not being awaited.

I have traced the error to the following line:

TUnit/TUnit.Core.SourceGenerator/Generators/HookMetadataGenerator.cs

Line 627 in fcbe27a

writer.AppendLine("await AsyncConvert.ConvertObject(() => result);");

It seems to be trying to convert result to something that can be awaited but since it is passing in a local Func<object> then it will always end up running syncFunc() in AsyncConvert which isn't the intention.

TUnit/TUnit.Core/AsyncConvert.cs

Lines 65 to 69 in fcbe27a

	if (invoke is Func<object> syncFunc)
	{
	syncFunc();
	return;
	}

To be clear, the before hook is being called, but TUnit continues execution without waiting for the async operation to complete so tests end up running before the hook is done running.

[DavidZidar]

I've worked around the problem for now by doing blocking waits in my before hooks.

[thomhurst]

@DavidZidar what's the return type of your hook? Task? ValueTask?

[DavidZidar]

Task

[thomhurst]

Can you create me a small repro please?
I'm not seeing it when I try to do this:

public class Tests
{
    private string _taskHook = string.Empty;
    private string _valueTaskHook = string.Empty;

    [Before(Test)]
    public async Task BeforeTest_Task()
    {
        await Task.Delay(TimeSpan.FromSeconds(5));
        _taskHook = "Task Hook Executed";
    }

    [Before(Test)]
    public async ValueTask BeforeTest_ValueTask()
    {
        await Task.Delay(TimeSpan.FromSeconds(5));
        _valueTaskHook = "ValueTask Hook Executed";
    }

    [Test]
    public async Task MyTest()
    {
        await Assert.That(_taskHook).IsEqualTo("Task Hook Executed");
        await Assert.That(_valueTaskHook).IsEqualTo("ValueTask Hook Executed");
    }
}

[thomhurst]

Nevermind I replicated it. Assuming you're using a generic class 😄

[DavidZidar]

Yes, I was just about to say, I managed to repro it with a generic base class (which is what my real tests are using).

public abstract class BaseClass<T>
{
	[Before(Test)]
	public async Task Setup()
	{
		await Task.Delay(1_000);

		Console.WriteLine("Setup completed"); // This never runs
	}
}

public class ReproTest : BaseClass<string>
{
    [Test]
    public void TestMethod()
    {
        Console.WriteLine("Test method executed");
    }
}

[DavidZidar]

So perhaps more of a corner case than I thought but it would be nice if it started working again. 😄

[thomhurst]

Should hopefully work now in the latest version 😄

[DavidZidar]

Works great! My tests passed and I also step debugged to verify, looks good. 😄 Thanks for the quick fix!