public async Task WriteAsync_PreferOperationCanceledException_MidExecution()
{
var handler = new DelayedWriter(this.sendingStream, this.receivingStream, new JsonMessageFormatter());
var cts = new CancellationTokenSource();
var writeTask = handler.WriteAsync(CreateRequestMessage(), cts.Token);
cts.Cancel();
await handler.DisposeAsync();
// Unblock writer. It should not throw anything as it is to emulate not recognizing the
// CancellationToken before completing its work.
handler.WriteBlock.Set();
await Assert.ThrowsAnyAsync <OperationCanceledException>(() => writeTask.AsTask());
}
