From: Marek Safar <marek.safar@gmail.com>
Date: Sat, 7 Dec 2013 14:40:52 +0000 (+0100)
Subject: [corlib] Add check for launching cancelled task to all overloads
X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=commitdiff_plain;h=395cf8f623cdf3754f1af0df096e83676133a643;p=mono.git

[corlib] Add check for launching cancelled task to all overloads
---

diff --git a/mcs/class/corlib/System.Threading.Tasks/TaskFactory.cs b/mcs/class/corlib/System.Threading.Tasks/TaskFactory.cs
index 607f08da4ec..a558c622c5e 100644
--- a/mcs/class/corlib/System.Threading.Tasks/TaskFactory.cs
+++ b/mcs/class/corlib/System.Threading.Tasks/TaskFactory.cs
@@ -214,9 +214,14 @@ namespace System.Threading.Tasks
 		                                        TaskCreationOptions creationOptions,
 		                                        TaskScheduler scheduler)
 		{
-			Task<TResult> t = new Task<TResult> (function, state, cancellationToken, creationOptions);
-			t.Start (scheduler);
+			var t = new Task<TResult> (function, state, cancellationToken, creationOptions);
 			
+			//
+			// Don't start cancelled task it would throw an exception
+			//
+			if (!t.IsCompleted)
+				t.Start (scheduler);
+
 			return t;
 		}
 		#endregion
diff --git a/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest.cs b/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest.cs
index f0f87a898f2..857841e326f 100644
--- a/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest.cs
+++ b/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest.cs
@@ -604,16 +604,24 @@ namespace MonoTests.System.Threading.Tasks
 		[Test]
 		public void StartNewCancelled ()
 		{
-			var cts = new CancellationTokenSource ();
-			cts.Cancel ();
+			var ct = new CancellationToken (true);
 
-			var task = factory.StartNew (() => Assert.Fail ("Should never be called"), cts.Token);
+			var task = factory.StartNew (() => Assert.Fail ("Should never be called"), ct);
 			try {
 				task.Start ();
+				Assert.Fail ("#1");
 			} catch (InvalidOperationException) {
 			}
 
 			Assert.IsTrue (task.IsCanceled, "#2");
+
+			task = factory.StartNew (() => { }, ct);
+			try {
+				task.Wait ();
+			} catch (AggregateException e) {
+				Assert.IsTrue (task.IsCanceled, "#3");
+				Assert.That (e.InnerException, Is.TypeOf (typeof (TaskCanceledException)), "#4");
+			}
 		}
 	}
 }
diff --git a/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest_T.cs b/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest_T.cs
index 0c30a093b03..ff964bb9cfc 100644
--- a/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest_T.cs
+++ b/mcs/class/corlib/Test/System.Threading.Tasks/TaskFactoryTest_T.cs
@@ -33,6 +33,9 @@ using System.Threading;
 using System.Threading.Tasks;
 
 using NUnit.Framework;
+#if !MOBILE
+using NUnit.Framework.SyntaxHelpers;
+#endif
 
 namespace MonoTests.System.Threading.Tasks
 {
@@ -249,6 +252,29 @@ namespace MonoTests.System.Threading.Tasks
 			Assert.AreEqual ("1", task.Result, "#2");
 		}
 
+		[Test]
+		public void StartNewCancelled ()
+		{
+			var ct = new CancellationToken (true);
+			var factory = new TaskFactory<int> ();
+
+			var task = factory.StartNew (() => { Assert.Fail ("Should never be called"); return 1; }, ct);
+			try {
+				task.Start ();
+				Assert.Fail ("#1");
+			} catch (InvalidOperationException) {
+			}
+
+			Assert.IsTrue (task.IsCanceled, "#2");
+
+			task = factory.StartNew (() => 1, ct);
+			try {
+				task.Wait ();
+			} catch (AggregateException e) {
+				Assert.IsTrue (task.IsCanceled, "#3");
+				Assert.That (e.InnerException, Is.TypeOf (typeof (TaskCanceledException)), "#4");
+			}
+		}
 	}
 }