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
  39 namespace MonoTests.System.Runtime.CompilerServices
  40 {
  41         [TestFixture]
  42         public class TaskAwaiterTest
  43         {
  44                 class Scheduler : TaskScheduler
  45                 {
  46                         string name;
  47                         int ic, qc;
  48
  49                         public Scheduler (string name)
  50                         {
  51                                 this.name = name;
  52                         }
  53
  54                         public int InlineCalls { get { return ic; } }
  55                         public int QueueCalls { get { return qc; } }
  56
  57                         protected override IEnumerable<Task> GetScheduledTasks ()
  58                         {
  59                                 throw new NotImplementedException ();
  60                         }
  61
  62                         protected override void QueueTask (Task task)
  63                         {
  64                                 Interlocked.Increment (ref qc);
  65                                 ThreadPool.QueueUserWorkItem (o => {
  66                                         TryExecuteTask (task);
  67                                 });
  68                         }
  69
  70                         protected override bool TryExecuteTaskInline (Task task, bool taskWasPreviouslyQueued)
  71                         {
  72                                 Interlocked.Increment (ref ic);
  73                                 return false;
  74                         }
  75                 }
  76
  77                 class SingleThreadSynchronizationContext : SynchronizationContext
  78                 {
  79                         readonly Queue _queue = new Queue ();
  80
  81                         public void RunOnCurrentThread ()
  82                         {
  83                                 while (_queue.Count != 0) {
  84                                         var workItem = (KeyValuePair<SendOrPostCallback, object>) _queue.Dequeue ();
  85                                         workItem.Key (workItem.Value);
  86                                 }
  87                         }
  88
  89                         public override void Post (SendOrPostCallback d, object state)
  90                         {
  91                                 if (d == null) {
  92                                         throw new ArgumentNullException ("d");
  93                                 }
  94
  95                                 _queue.Enqueue (new KeyValuePair<SendOrPostCallback, object> (d, state));
  96                         }
  97
  98                         public override void Send (SendOrPostCallback d, object state)
  99                         {
 100                                 throw new NotSupportedException ("Synchronously sending is not supported.");
 101                         }
 102                 }
 103
 104                 string progress;
 105                 SynchronizationContext sc;
 106                 ManualResetEvent mre;
 107
 108                 [SetUp]
 109                 public void Setup ()
 110                 {
 111                         sc = SynchronizationContext.Current;
 112                 }
 113
 114                 [TearDown]
 115                 public void TearDown ()
 116                 {
 117                         SynchronizationContext.SetSynchronizationContext (sc);
 118                 }
 119
 120                 [Test]
 121                 public void GetResultFaulted ()
 122                 {
 123                         TaskAwaiter awaiter;
 124
 125                         var task = new Task (() => { throw new ApplicationException (); });
 126                         awaiter = task.GetAwaiter ();
 127                         task.RunSynchronously (TaskScheduler.Current);
 128
 129
 130                         Assert.IsTrue (awaiter.IsCompleted);
 131
 132                         try {
 133                                 awaiter.GetResult ();
 134                                 Assert.Fail ();
 135                         } catch (ApplicationException) {
 136                         }
 137                 }
 138
 139                 [Test]
 140                 public void GetResultCanceled ()
 141                 {
 142                         TaskAwaiter awaiter;
 143
 144                         var token = new CancellationToken (true);
 145                         var task = new Task (() => { }, token);
 146                         awaiter = task.GetAwaiter ();
 147
 148                         try {
 149                                 awaiter.GetResult ();
 150                                 Assert.Fail ();
 151                         } catch (TaskCanceledException) {
 152                         }
 153                 }
 154
 155                 [Test]
 156                 public void GetResultWaitOnCompletion ()
 157                 {
 158                         TaskAwaiter awaiter;
 159
 160                         var task = Task.Delay (30);
 161                         awaiter = task.GetAwaiter ();
 162
 163                         awaiter.GetResult ();
 164                         Assert.AreEqual (TaskStatus.RanToCompletion, task.Status);
 165                 }
 166
 167                 [Test]
 168                 public void CustomScheduler ()
 169                 {
 170                         // some test runners (e.g. Touch.Unit) will execute this on the main thread and that would lock them
 171                         if (!Thread.CurrentThread.IsBackground)
 172                                 Assert.Ignore ("Current thread is not running in the background.");
 173
 174                         var a = new Scheduler ("a");
 175                         var b = new Scheduler ("b");
 176
 177                         var t = TestCS (a, b);
 178                         Assert.IsTrue (t.Wait (3000), "#0");
 179                         Assert.AreEqual (0, t.Result, "#1");
 180                         Assert.AreEqual (0, b.InlineCalls, "#2b");
 181                         Assert.AreEqual (2, a.QueueCalls, "#3a");
 182                         Assert.AreEqual (1, b.QueueCalls, "#3b");
 183                 }
 184
 185                 static async Task<int> TestCS (TaskScheduler schedulerA, TaskScheduler schedulerB)
 186                 {
 187                         var res = await Task.Factory.StartNew (async () => {
 188                                 if (TaskScheduler.Current != schedulerA)
 189                                         return 1;
 190
 191                                 await Task.Factory.StartNew (
 192                                         () => {
 193                                                 if (TaskScheduler.Current != schedulerB)
 194                                                         return 2;
 195
 196                                                 return 0;
 197                                         }, CancellationToken.None, TaskCreationOptions.None, schedulerB);
 198
 199                                 if (TaskScheduler.Current != schedulerA)
 200                                         return 3;
 201
 202                                 return 0;
 203                         }, CancellationToken.None, TaskCreationOptions.None, schedulerA);
 204
 205                         return res.Result;
 206                 }
 207
 208                 [Test]
 209                 public void FinishedTaskOnCompleted ()
 210                 {
 211                         var mres = new ManualResetEvent (false);
 212                         var mres2 = new ManualResetEvent (false);
 213
 214                         var tcs = new TaskCompletionSource<object> ();
 215                         tcs.SetResult (null);
 216                         var task = tcs.Task;
 217
 218                         var awaiter = task.GetAwaiter ();
 219                         Assert.IsTrue (awaiter.IsCompleted, "#1");
 220
 221                         awaiter.OnCompleted(() => {
 222                                 if (mres.WaitOne (1000))
 223                                         mres2.Set ();
 224                         });
 225
 226                         mres.Set ();
 227                         // this will only terminate correctly if the test was not executed from the main thread
 228                         // e.g. Touch.Unit defaults to run tests on the main thread and this will return false
 229                         Assert.AreEqual (Thread.CurrentThread.IsBackground, mres2.WaitOne (2000), "#2");;
 230                 }
 231
 232                 [Test]
 233                 public void CompletionOnSameCustomSynchronizationContext ()
 234                 {
 235                         progress = "";
 236                         var syncContext = new SingleThreadSynchronizationContext ();
 237                         SynchronizationContext.SetSynchronizationContext (syncContext);
 238
 239                         syncContext.Post (delegate {
 240                                 Go (syncContext);
 241                         }, null);
 242
 243                         // Custom message loop
 244                         var cts = new CancellationTokenSource ();
 245                         cts.CancelAfter (5000);
 246                         while (progress.Length != 3 && !cts.IsCancellationRequested) {
 247                                 syncContext.RunOnCurrentThread ();
 248                                 Thread.Sleep (0);
 249                         }
 250
 251                         Assert.AreEqual ("123", progress);
 252                 }
 253
 254                 async void Go (SynchronizationContext ctx)
 255                 {
 256                         await Wait (ctx);
 257
 258                         progress += "2";
 259                 }
 260
 261                 async Task Wait (SynchronizationContext ctx)
 262                 {
 263                         await Task.Delay (10); // Force block suspend/return
 264
 265                         ctx.Post (l => progress += "3", null);
 266
 267                         progress += "1";
 268
 269                         // Exiting same context - no need to post continuation
 270                 }
 271
 272                 [Test]
 273                 public void CompletionOnDifferentCustomSynchronizationContext ()
 274                 {
 275                         mre = new ManualResetEvent (false);
 276                         progress = "";
 277                         var syncContext = new SingleThreadSynchronizationContext ();
 278                         SynchronizationContext.SetSynchronizationContext (syncContext);
 279
 280                         syncContext.Post (delegate {
 281                                 Go2 (syncContext);
 282                         }, null);
 283
 284                         // Custom message loop
 285                         var cts = new CancellationTokenSource ();
 286                         cts.CancelAfter (5000);
 287                         while (progress.Length != 3 && !cts.IsCancellationRequested) {
 288                                 syncContext.RunOnCurrentThread ();
 289                                 Thread.Sleep (0);
 290                         }
 291
 292                         Assert.AreEqual ("132", progress);
 293                 }
 294
 295                 async void Go2 (SynchronizationContext ctx)
 296                 {
 297                         await Wait2 (ctx);
 298
 299                         if (mre.WaitOne (5000))
 300                                 progress += "2";
 301                 }
 302
 303                 async Task Wait2 (SynchronizationContext ctx)
 304                 {
 305                         await Task.Delay (10); // Force block suspend/return
 306
 307                         ctx.Post (l => {
 308                                 progress += "3";
 309                                 mre.Set ();
 310                         }, null);
 311
 312                         progress += "1";
 313
 314                         SynchronizationContext.SetSynchronizationContext (null);
 315                 }
 316         }
 317 }
 318
 319 #endif