Bug 470 - Missing System.Threading.Tasks.TaskSchedulerException
Summary: Missing System.Threading.Tasks.TaskSchedulerException
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: master
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Jérémie Laval
Depends on:
Reported: 2011-08-26 07:27 UTC by Marek Safar
Modified: 2011-08-28 09:12 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Marek Safar 2011-08-26 07:27:49 UTC
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Threading.Tasks;

class TestScheduler : TaskScheduler
	protected override void QueueTask (Task task)
		throw new NotImplementedException ();

	protected override bool TryDequeue (Task task)
		throw new NotImplementedException ();

	protected override bool TryExecuteTaskInline (Task task, bool taskWasPreviouslyQueued)
		return true;

	protected override IEnumerable<Task> GetScheduledTasks ()
		throw new NotImplementedException ();

class C
	public static void Main ()
		var ts = new TestScheduler ();
		Task t = new Task (() => {});
		t.RunSynchronously (ts);


Mono: nothing

Unhandled Exception: System.Threading.Tasks.TaskSchedulerException: An exception was thrown by a TaskScheduler. ---> System.InvalidOperationException: The TryExecuteTaskInline call to the underlying scheduler succeeded, but the task body was not invoked.
   at System.Threading.Tasks.TaskScheduler.TryRunInline(Task task, Boolean taskWasPreviouslyQueued, Object threadStatics)
   at System.Threading.Tasks.Task.InternalRunSynchronously(TaskScheduler scheduler)
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.InternalRunSynchronously(TaskScheduler scheduler)
   at C.Main()
Comment 1 Jérémie Laval 2011-08-28 09:12:57 UTC
Fixed in master/f3cfa2841c9637add582. Do you need it backported to mono-2-10 too?