False RCS1229

[NN---]

Product and Version Used:
Roslynator.Analyzers 3.2.0

Steps to Reproduce:

using System;
using System.Threading;
using System.Threading.Tasks;

[assembly:CLSCompliant(false)]

namespace ConsoleApp1
{
    public static class Program
    {
        private static ValueTask<int> ReceiveAsync(byte[] data, CancellationToken token)
        {
            using var cancellations = CancellationTokenSource.CreateLinkedTokenSource(token, token);

            return ValueTask.FromResult(data.Length);
        }

        public static void Main()
        {
        }
    }
}

Actual Behavior:

Severity	Code	Description	Project	File	Line	Suppression State
Message	RCS1229	Use async/await when necessary.	

Expected Behavior:
No message

[josefpihrt]

Hi, I'm not able to reproduce described behavior with the exact same code, no diagnostic is reported.

[NN---]

Fixed sample.
It needed few more lines.

[josefpihrt]

I think that analyzer is right in this case. For further explanation see "The curious case of async, await, and IDisposable"

[NN---]

The method is totally synchronous , why do I need to make it async and have performance degradation ?

[josefpihrt]

Oh, you mean that in the case where Task.FromResult is used the diagnostic should not be reported?

[NN---]

Yes.
There is no point to make method async if there is direct return using Value/Task.FromResult/Cancellation/Exception

[josefpihrt]

That makes sense.