AssertionExtensions.Awaiting Task method is ambiguous with ValueTask

With .net core and c# 8 how are you supposed to use the AssertionExtensions.Awaiting methods? The following code worked before ValueTask was added, but now will give the following compile time error

The call is ambiguous between the following methods or properties: ‘AssertionExtensions.Awaiting<T>(T, Func<T, Task>)’ and ‘AssertionExtensions.Awaiting<T>(T, Func<T, ValueTask>)’

[Test]
public async Task TestFoo()
{
    var foo = new Foo();

    foo.Awaiting(async f => await f.BarAsync()).Should().NotThrow(); //<--compiler error
}

public class Foo
{
    public Task BarAsync() => Task.FromResult(0);
}

[CraigRice]

Some related information:

I had a similar issue when having to force LangVersion 6 on an old project (to use c# 6), the Should() assertion extensions wouldn’t compile with “The call is ambiguous between the following methods or properties: ‘DataRowAssertionExtensions.Should<TDataRow>(TDataRow)’ and ‘DataSetAssertionExtensions.Should<TDataSet>(TDataSet)’”.

The workaround is changing “using FluentAssertions;” to “using static FluentAssertions.AssertionExtensions;”

[markusschaber]

The example here still advises async + await: https://fluentassertions.com/exceptions/

Alternatively, you can use the Awaiting method like this:

Func<Task> act = () => asyncObject.Awaiting(async x => await x.ThrowAsync<ArgumentException>()); act.Should().Throw<ArgumentException>();