Task.Wait doesn't propagate exception

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

namespace ConsoleApp14
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                var cts = new CancellationTokenSource();
                var task = Task.Run(
                    async () =>
                    {

                            await Task.Delay(TimeSpan.FromSeconds(10), cts.Token);

                    },
                    cts.Token);
                cts.CancelAfter(TimeSpan.FromSeconds(1));
                task.Wait();

                // .NET 2.0 - 3.5 reach this line
                Console.WriteLine("Must not get there");
            }
            catch (AggregateException)
            {
                Console.WriteLine("Expected");
            }
        }
    }
}

I guess related to #120

[theraot]

Trying the code above in .NET 2.0 throws an AggregateException with TaskCanceledException with a CancellationToken with IsCancellationRequested = true. While the same code in LinqPad has IsCancellationRequested = false.

I can also confirm that Unwrap should copy the CancellationToken.

Edit: that is a total of 3 things to fix:

• TrySetCanceled should not set a CancellationToken
• Task should throw even without CancellationToken.IsCancellationRequested
• Unwrap should copy the CancellationToken

[theraot]

This happens: The Task gets marked cancelled, but the CancellationToken on the Task says that no cancellation was requested. Why? Because the task has a CancellationToken from the default source. Why? Because Task.Run uses Unwrap and Unwrap does not copy the CancellationToken. I’ll fix that.