mcs/class/corlib/Test/System.Runtime.CompilerServices/TaskAwaiterTest.cs

   1 //
   2 // TaskAwaiterTest.cs
   3 //
   4 // Authors:
   5 //      Marek Safar  <marek.safar@gmail.com>
   6 //
   7 // Copyright (C) 2011 Xamarin, Inc (http://www.xamarin.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 #if NET_4_5
  30
  31 using System;
  32 using System.Threading;
  33 using System.Threading.Tasks;
  34 using NUnit.Framework;
  35 using System.Runtime.CompilerServices;
  36 using System.Collections.Generic;
  37 using System.Collections;
  38 using System.Collections.Concurrent;
  39
  40 namespace MonoTests.System.Runtime.CompilerServices
  41 {
  42         [TestFixture]
  43         public class TaskAwaiterTest
  44         {
  45                 class Scheduler : TaskScheduler
  46                 {
  47                         string name;
  48                         int ic, qc;
  49
  50                         public Scheduler (string name)
  51                         {
  52                                 this.name = name;
  53                         }
  54
  55                         public int InlineCalls { get { return ic; } }
  56                         public int QueueCalls { get { return qc; } }
  57
  58                         protected override IEnumerable<Task> GetScheduledTasks ()
  59                         {
  60                                 throw new NotImplementedException ();
  61                         }
  62
  63                         protected override void QueueTask (Task task)
  64                         {
  65                                 Interlocked.Increment (ref qc);
  66                                 ThreadPool.QueueUserWorkItem (o => {
  67                                         TryExecuteTask (task);
  68                                 });
  69                         }
  70
  71                         protected override bool TryExecuteTaskInline (Task task, bool taskWasPreviouslyQueued)
  72                         {
  73                                 Interlocked.Increment (ref ic);
  74                                 return false;
  75                         }
  76
  77                         public override string ToString ()
  78                         {
  79                                 return "Scheduler-" + name;
  80                         }
  81                 }
  82
  83                 class SingleThreadSynchronizationContext : SynchronizationContext
  84                 {
  85                         readonly Queue _queue = new Queue ();
  86
  87                         public void RunOnCurrentThread ()
  88                         {
  89                                 while (_queue.Count != 0) {
  90                                         var workItem = (KeyValuePair<SendOrPostCallback, object>) _queue.Dequeue ();
  91                                         workItem.Key (workItem.Value);
  92                                 }
  93                         }
  94
  95                         public override void Post (SendOrPostCallback d, object state)
  96                         {
  97                                 if (d == null) {
  98                                         throw new ArgumentNullException ("d");
  99                                 }
 100
 101                                 _queue.Enqueue (new KeyValuePair<SendOrPostCallback, object> (d, state));
 102                         }
 103
 104                         public override void Send (SendOrPostCallback d, object state)
 105                         {
 106                                 throw new NotSupportedException ("Synchronously sending is not supported.");
 107                         }
 108                 }
 109
 110                 class NestedSynchronizationContext : SynchronizationContext
 111                 {
 112                         Thread thread;
 113                         readonly ConcurrentQueue<Tuple<SendOrPostCallback, object, ExecutionContext>> workQueue = new ConcurrentQueue<Tuple<SendOrPostCallback, object, ExecutionContext>> ();
 114                         readonly AutoResetEvent workReady = new AutoResetEvent (false);
 115
 116                         public NestedSynchronizationContext ()
 117                         {
 118                                 thread = new Thread (WorkerThreadProc) { IsBackground = true };
 119                                 thread.Start ();
 120                         }
 121
 122                         public override void Post (SendOrPostCallback d, object state)
 123                         {
 124                                 var context = ExecutionContext.Capture ();
 125                                 workQueue.Enqueue (Tuple.Create (d, state, context));
 126                                 workReady.Set ();
 127                         }
 128
 129                         void WorkerThreadProc ()
 130                         {
 131                                 if (!workReady.WaitOne (10000))
 132                                         return;
 133
 134                                 Tuple<SendOrPostCallback, object, ExecutionContext> work;
 135
 136                                 while (workQueue.TryDequeue (out work)) {
 137                                         ExecutionContext.Run (work.Item3, _ => {
 138                                                 var oldSyncContext = SynchronizationContext.Current;
 139                                                 SynchronizationContext.SetSynchronizationContext (this);
 140                                                 work.Item1 (_);
 141                                                 SynchronizationContext.SetSynchronizationContext (oldSyncContext);
 142                                         }, work.Item2);
 143                                 }
 144                         }
 145                 }
 146
 147                 string progress;
 148                 SynchronizationContext sc;
 149                 ManualResetEvent mre;
 150
 151                 [SetUp]
 152                 public void Setup ()
 153                 {
 154                         sc = SynchronizationContext.Current;
 155                 }
 156
 157                 [TearDown]
 158                 public void TearDown ()
 159                 {
 160                         SynchronizationContext.SetSynchronizationContext (sc);
 161                 }
 162
 163                 [Test]
 164                 public void GetResultFaulted ()
 165                 {
 166                         TaskAwaiter awaiter;
 167
 168                         var task = new Task (() => { throw new ApplicationException (); });
 169                         awaiter = task.GetAwaiter ();
 170                         task.RunSynchronously (TaskScheduler.Current);
 171
 172
 173                         Assert.IsTrue (awaiter.IsCompleted);
 174
 175                         try {
 176                                 awaiter.GetResult ();
 177                                 Assert.Fail ();
 178                         } catch (ApplicationException) {
 179                         }
 180                 }
 181
 182                 [Test]
 183                 public void GetResultCanceled ()
 184                 {
 185                         TaskAwaiter awaiter;
 186
 187                         var token = new CancellationToken (true);
 188                         var task = new Task (() => { }, token);
 189                         awaiter = task.GetAwaiter ();
 190
 191                         try {
 192                                 awaiter.GetResult ();
 193                                 Assert.Fail ();
 194                         } catch (TaskCanceledException) {
 195                         }
 196                 }
 197
 198                 [Test]
 199                 public void GetResultWaitOnCompletion ()
 200                 {
 201                         TaskAwaiter awaiter;
 202
 203                         var task = Task.Delay (30);
 204                         awaiter = task.GetAwaiter ();
 205
 206                         awaiter.GetResult ();
 207                         Assert.AreEqual (TaskStatus.RanToCompletion, task.Status);
 208                 }
 209
 210                 [Test]
 211                 public void CustomScheduler ()
 212                 {
 213                         // some test runners (e.g. Touch.Unit) will execute this on the main thread and that would lock them
 214                         if (!Thread.CurrentThread.IsBackground)
 215                                 Assert.Ignore ("Current thread is not running in the background.");
 216
 217                         var a = new Scheduler ("a");
 218                         var b = new Scheduler ("b");
 219
 220                         var t = TestCS (a, b);
 221                         Assert.IsTrue (t.Wait (3000), "#0");
 222                         Assert.AreEqual (0, t.Result, "#1");
 223                         Assert.AreEqual (0, b.InlineCalls, "#2b");
 224                         Assert.IsTrue (a.QueueCalls == 1 || a.QueueCalls == 2, "#3a");
 225                         Assert.AreEqual (1, b.QueueCalls, "#3b");
 226                 }
 227
 228                 static async Task<int> TestCS (TaskScheduler schedulerA, TaskScheduler schedulerB)
 229                 {
 230                         var res = await Task.Factory.StartNew (async () => {
 231                                 if (TaskScheduler.Current != schedulerA)
 232                                         return 1;
 233
 234                                 await Task.Factory.StartNew (
 235                                         () => {
 236                                                 if (TaskScheduler.Current != schedulerB)
 237                                                         return 2;
 238
 239                                                 return 0;
 240                                         }, CancellationToken.None, TaskCreationOptions.None, schedulerB);
 241
 242                                 if (TaskScheduler.Current != schedulerA)
 243                                         return 3;
 244
 245                                 return 0;
 246                         }, CancellationToken.None, TaskCreationOptions.None, schedulerA);
 247
 248                         return res.Result;
 249                 }
 250
 251 #if !MOBILE_STATIC
 252                 [Test]
 253                 public void FinishedTaskOnCompleted ()
 254                 {
 255                         var mres = new ManualResetEvent (false);
 256                         var mres2 = new ManualResetEvent (false);
 257
 258                         var tcs = new TaskCompletionSource<object> ();
 259                         tcs.SetResult (null);
 260                         var task = tcs.Task;
 261
 262                         var awaiter = task.GetAwaiter ();
 263                         Assert.IsTrue (awaiter.IsCompleted, "#1");
 264
 265                         awaiter.OnCompleted(() => {
 266                                 if (mres.WaitOne (1000))
 267                                         mres2.Set ();
 268                         });
 269
 270                         mres.Set ();
 271                         // this will only terminate correctly if the test was not executed from the main thread
 272                         // e.g. Touch.Unit defaults to run tests on the main thread and this will return false
 273                         Assert.AreEqual (Thread.CurrentThread.IsBackground, mres2.WaitOne (2000), "#2");;
 274                 }
 275
 276 #endif
 277
 278                 [Test]
 279                 public void CompletionOnSameCustomSynchronizationContext ()
 280                 {
 281                         progress = "";
 282                         var syncContext = new SingleThreadSynchronizationContext ();
 283                         SynchronizationContext.SetSynchronizationContext (syncContext);
 284
 285                         syncContext.Post (delegate {
 286                                 Go (syncContext);
 287                         }, null);
 288
 289                         // Custom message loop
 290                         var cts = new CancellationTokenSource ();
 291                         cts.CancelAfter (5000);
 292                         while (progress.Length != 3 && !cts.IsCancellationRequested) {
 293                                 syncContext.RunOnCurrentThread ();
 294                                 Thread.Sleep (0);
 295                         }
 296
 297                         Assert.AreEqual ("123", progress);
 298                 }
 299
 300                 async void Go (SynchronizationContext ctx)
 301                 {
 302                         await Wait (ctx);
 303
 304                         progress += "2";
 305                 }
 306
 307                 async Task Wait (SynchronizationContext ctx)
 308                 {
 309                         await Task.Delay (10); // Force block suspend/return
 310
 311                         ctx.Post (l => progress += "3", null);
 312
 313                         progress += "1";
 314
 315                         // Exiting same context - no need to post continuation
 316                 }
 317
 318                 [Test]
 319                 public void CompletionOnDifferentCustomSynchronizationContext ()
 320                 {
 321                         mre = new ManualResetEvent (false);
 322                         progress = "";
 323                         var syncContext = new SingleThreadSynchronizationContext ();
 324                         SynchronizationContext.SetSynchronizationContext (syncContext);
 325
 326                         syncContext.Post (delegate {
 327                                 Task t = new Task (delegate() { });
 328                                 Go2 (syncContext, t);
 329                                 t.Start ();
 330                         }, null);
 331
 332                         // Custom message loop
 333                         var cts = new CancellationTokenSource ();
 334                         cts.CancelAfter (5000);
 335                         while (progress.Length != 3 && !cts.IsCancellationRequested) {
 336                                 syncContext.RunOnCurrentThread ();
 337                                 Thread.Sleep (0);
 338                         }
 339
 340                         Assert.AreEqual ("13xa2", progress);
 341                 }
 342
 343                 async void Go2 (SynchronizationContext ctx, Task t)
 344                 {
 345                         await Wait2 (ctx, t);
 346
 347                         progress += "a";
 348
 349                         if (mre.WaitOne (5000))
 350                                 progress += "2";
 351                         else
 352                                 progress += "b";
 353                 }
 354
 355                 async Task Wait2 (SynchronizationContext ctx, Task t)
 356                 {
 357                         await t; // Force block suspend/return
 358
 359                         ctx.Post (l => {
 360                                 progress += "3";
 361                                 mre.Set ();
 362                                 progress += "x";
 363                         }, null);
 364
 365                         progress += "1";
 366
 367                         SynchronizationContext.SetSynchronizationContext (null);
 368                 }
 369
 370                 [Test]
 371                 public void NestedLeakingSynchronizationContext ()
 372                 {
 373                         var sc = SynchronizationContext.Current;
 374                         if (sc == null)
 375                                 Assert.IsTrue (NestedLeakingSynchronizationContext_MainAsync (sc).Wait (5000), "#1");
 376                         else
 377                                 Assert.Ignore ("NestedSynchronizationContext may never complete on custom context");
 378                 }
 379
 380                 static async Task NestedLeakingSynchronizationContext_MainAsync (SynchronizationContext sc)
 381                 {
 382                         Assert.AreSame (sc, SynchronizationContext.Current, "#1");
 383                         await NestedLeakingSynchronizationContext_DoWorkAsync ();
 384                         Assert.AreSame (sc, SynchronizationContext.Current, "#2");
 385                 }
 386
 387                 static async Task NestedLeakingSynchronizationContext_DoWorkAsync ()
 388                 {
 389                         var sc = new NestedSynchronizationContext ();
 390                         SynchronizationContext.SetSynchronizationContext (sc);
 391
 392                         Assert.AreSame (sc, SynchronizationContext.Current);
 393                         await Task.Yield ();
 394                         Assert.AreSame (sc, SynchronizationContext.Current);
 395                 }
 396         }
 397 }
 398
 399 #endif