public static void RunContinueWithPreCancelTests_State()
{
Action <Task, bool, string> EnsureCompletionStatus = delegate(Task task, bool shouldBeCompleted, string message)
{
if (task.IsCompleted != shouldBeCompleted)
{
Assert.True(false, string.Format(string.Format("RunContinueWithPreCancelTests_State: > FAILED. {0}.", message)));
}
};
CancellationTokenSource cts = new CancellationTokenSource();
cts.Cancel();
ManualResetEvent mres = new ManualResetEvent(false);
// Pre-increment the dontCounts for pre-canceled continuations to make final check easier
// (i.e., all counts should be 1 at end).
int[] doneCount = { 0, 0, 1, 0, 1, 0 };
string stateParam = "test"; //used as a state parametr for the continuation if the useStateParam is true
Task t1 = new Task(delegate { doneCount[0]++; });
Task c1 = t1.ContinueWith((_, obj) => { doneCount[1]++; }, stateParam);
Task c2 = c1.ContinueWith((_, obj) => { mres.WaitOne(); doneCount[2]++; }, stateParam, cts.Token);
Task c3 = c2.ContinueWith((_, obj) => { mres.WaitOne(); doneCount[3]++; }, stateParam);
Task c4 = c3.ContinueWith((_, obj) => { mres.WaitOne(); doneCount[4]++; }, stateParam,
cts.Token, TaskContinuationOptions.LazyCancellation, TaskScheduler.Default);
Task c5 = c4.ContinueWith((_, obj) => { mres.WaitOne(); doneCount[5]++; }, stateParam);
EnsureCompletionStatus(c2, true, " c2 should have completed (canceled) upon construction");
EnsureCompletionStatus(c4, false, " c4 should NOT have completed (canceled) upon construction");
EnsureCompletionStatus(t1, false, " t1 should NOT have completed before being started");
EnsureCompletionStatus(c1, false, " c1 should NOT have completed before antecedent completed");
EnsureCompletionStatus(c3, false, " c3 should NOT have completed before mres was set");
EnsureCompletionStatus(c5, false, " c5 should NOT have completed before mres was set");
// These should be done already. And Faulted.
Exception exception = null;
try
{
c2.Wait();
Assert.True(false, string.Format("RunContinueWithPreCancelTests_State: Expected c2.Wait to throw AE/TCE"));
}
catch (Exception ex)
{
exception = ex;
}
EnsureExceptionIsAEofTCE(exception, "RunContinueWithPreCancelTests_State: Expected c2.Wait to throw AE/TCE");
mres.Set();
Debug.WriteLine("RunContinueWithPreCancelTests_State: Waiting for tasks to complete... if we hang here, something went wrong.");
c3.Wait();
try
{
c4.Wait();
Assert.True(false, string.Format("RunContinueWithPreCancelTests_State: Expected c4.Wait to throw AE/TCE"));
}
catch (Exception ex)
{
exception = ex;
}
EnsureExceptionIsAEofTCE(exception, "RunContinueWithPreCancelTests_State: Expected c4.Wait to throw AE/TCE");
c5.Wait();
EnsureCompletionStatus(t1, false, " t1 should NOT have completed (post-mres.Set()) before being started");
EnsureCompletionStatus(c1, false, " c1 should NOT have completed (post-mres.Set()) before antecedent completed");
t1.Start();
c1.Wait();
for (int i = 0; i < 6; i++)
{
if (doneCount[i] != 1)
{
Assert.True(false, string.Format("RunContinueWithPreCancelTests_State: > FAILED. doneCount[{0}] should be 1, is {1}", i, doneCount[i]));
}
}
}
public static Task <IEnumerable <TResult> > AsIEnumerable <TResult>(this Task <TResult[]> task)
{
return(task.ContinueWith(t => t.Result as IEnumerable <TResult>));
}