public static async Task ConfigureTopologyAsync(this Link @this,
Func<ILinkTopologyConfig, Task> configure, CancellationToken cancellationToken)
{
var completion = new TaskCompletionSource();
if (cancellationToken.IsCancellationRequested)
{
completion.TrySetCanceled();
await completion.Task;
return;
}
using (@this.CreateTopologyConfigurator(configure, () =>
{
completion.TrySetResultWithBackgroundContinuations();
return Task.FromResult((object) null);
}, ex =>
{
completion.TrySetExceptionWithBackgroundContinuations(ex);
return Task.FromResult((object) null);
}))
{
IDisposable registration = null;
try
{
registration = cancellationToken.Register(() =>
{
completion.TrySetCanceledWithBackgroundContinuations();
});
}
catch (ObjectDisposedException)
{
// Cancellation source already disposed
}
if (cancellationToken.IsCancellationRequested)
{
completion.TrySetCanceledWithBackgroundContinuations();
}
try
{
await completion.Task
.ConfigureAwait(false);
}
finally
{
registration?.Dispose();
}
}
}
public void TrySetExceptionsWithBackgroundContinuations_RunsOnAnotherThread()
{
AsyncContext.Run(async () =>
{
var unitTestThreadId = Thread.CurrentThread.ManagedThreadId;
int continuationThreadId = unitTestThreadId;
var tcs = new TaskCompletionSource();
var continuation = tcs.Task.ContinueWith(_ => { continuationThreadId = Thread.CurrentThread.ManagedThreadId; },
CancellationToken.None, TaskContinuationOptions.ExecuteSynchronously, TaskScheduler.Default);
tcs.TrySetExceptionWithBackgroundContinuations(new[] { new NotImplementedException() });
await continuation;
Assert.AreNotEqual(unitTestThreadId, continuationThreadId);
});
}
public void TrySetExceptionsWithBackgroundContinuationsTResult_RunsOnAnotherThread()
{
Test.Async(async () =>
{
var unitTestThreadId = Thread.CurrentThread.ManagedThreadId;
int continuationThreadId = unitTestThreadId;
var tcs = new TaskCompletionSource<int>();
var continuation = tcs.Task.ContinueWith(_ => { continuationThreadId = Thread.CurrentThread.ManagedThreadId; },
TaskContinuationOptions.ExecuteSynchronously);
tcs.TrySetExceptionWithBackgroundContinuations(new[] { new NotImplementedException() });
await continuation;
Assert.AreNotEqual(unitTestThreadId, continuationThreadId);
});
}
