ConfigureAwait(false) still continue on captured context when using Async Targeting Pack by Oscar Hansson

Thanks for the report. This is fixed in the latest internal builds, and will be available in the next update of the Microsoft.Bcl.Async pack.

Thanks for reporting this Oscar - we've confirmed that this is a bug, looks like we were ignoring the 'continueOnCapturedContext' parameter. We should have this fixed in the next update of the Microsoft.Bcl.Async package.

Regards

David Kean
BCL Team

I'm not sure that you could expect the same output from the two methods.

It's more clear to me what result to expect if we observe the thread id instead of task id. Modifying the two methods slightly, should result in same output behavior, that means both MainLines should NOT have the same id.

        public async void Test()
        {
            Debug.WriteLine("MainLine({0})", Thread.CurrentThread.ManagedThreadId);
            await TaskEx.Run(() =>
                {
                    Debug.WriteLine("Task({0})", Thread.CurrentThread.ManagedThreadId);
                }).ConfigureAwait(false);
            Debug.WriteLine("MainLine({0})", Thread.CurrentThread.ManagedThreadId);
        }

        public void Test2()
        {
            Debug.WriteLine("MainLine({0})", Thread.CurrentThread.ManagedThreadId);
            TaskEx.Run(() => Debug.WriteLine("Task({0})", Thread.CurrentThread.ManagedThreadId)).
                ContinueWith(antecedent =>
                {
                    Debug.WriteLine("MainLine({0})", Thread.CurrentThread.ManagedThreadId);
                }, TaskScheduler.Default);
        }

Example of expected output (VS 2012 on .NET 4.5 targeting .NET 4.5 Win7):
Test method 1:
MainLine(8)
Task(9)
MainLine(10)
Test method 2:
MainLine(8)
Task(10)
MainLine(10)

Example of unexpected output (VS 2012 on .NET 4.5 targeting .NET 4.0 with Async Targeting Pack Win7):
Test method 1:
MainLine(10)     <----------- Main thread
Task(6)
MainLine(10)     <----------- Should NOT run on the main thread (id=10)
Test method 2:
MainLine(10)
Task(11)
MainLine(11)

I've noticed the same thing with both the async targeting pack (Silverlight 5) and the new microsoft.bcl.async pack (Silverlight 4) (http://blogs.msdn.com/b/bclteam/archive/2012/10/19/using-async-await-without-net-framework-4-5.aspx)

I would expect the same output from both of these routines, however they don't match!

        public async void Test()
        {
            Debug.WriteLine("MainLine({0})", Task.CurrentId);
            await TaskEx.Run(() => Debug.WriteLine("Task({0})", Task.CurrentId)).ConfigureAwait(false);
            Debug.WriteLine("MainLine({0})", Task.CurrentId);
        }

        public void Test2()
        {
            Debug.WriteLine("MainLine({0})", Task.CurrentId);
            TaskEx.Run(() => Debug.WriteLine("Task({0})", Task.CurrentId)).ContinueWith(antecedent =>
            {
                Debug.WriteLine("MainLine({0})", Task.CurrentId);
            });
        }

Jay

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