better disposal. better tests.

Author: Martin Lercher

src/JsonRpc/ProcessScheduler.cs

@@ -56,7 +56,7 @@ private List<Task> RemoveCompleteTasks(List<Task> list)
             return result;
         }
 
-
+        public long _TestOnly_NonCompleteTaskCount = 0;
         private void ProcessRequestQueue()
         {
             // see https://github.com/OmniSharp/csharp-language-server-protocol/issues/4
@@ -82,6 +82,7 @@ private void ProcessRequestQueue()
                         else
                             throw new NotImplementedException("Only Serial and Parallel execution types can be handled currently");
                         waitables = RemoveCompleteTasks(waitables);
+                        Interlocked.Exchange(ref _TestOnly_NonCompleteTaskCount, waitables.Count);
                     }
                 }
             }
@@ -91,18 +92,21 @@ private void ProcessRequestQueue()
                     throw;
                 // OperationCanceledException - The CancellationToken has been canceled.
                 Task.WaitAll(waitables.ToArray(), TimeSpan.FromMilliseconds(1000));
-                waitables.ForEach((t) =>
+                var keeponrunning = RemoveCompleteTasks(waitables);
+                Interlocked.Exchange(ref _TestOnly_NonCompleteTaskCount, keeponrunning.Count);
+                keeponrunning.ForEach((t) =>
                 {
-                    if (!t.IsCompleted) {
-                        // TODO: There is no way to abort a Task. As we don't construct the tasks, we can do nothing here
-                        // Option is: change the task factory "Func<Task> request" to a "Func<CancellationToken, Task> request"
-                    }
+                    // TODO: There is no way to abort a Task. As we don't construct the tasks, we can do nothing here
+                    // Option is: change the task factory "Func<Task> request" to a "Func<CancellationToken, Task> request"
                 });
             }
         }
 
+        private bool _disposed = false;
         public void Dispose()
         {
+            if (_disposed) return;
+            _disposed = true;
             _cancel.Cancel();
             _thread.Join();
             _cancel.Dispose();

test/JsonRpc.Tests/ProcessSchedulerTests.cs

@@ -33,7 +33,7 @@ public void ShouldScheduleCompletedTask(RequestProcessType type)
                     done.Signal();
                     return Task.CompletedTask;
                 });
-                done.Wait(ALONGTIME_MS).Should().Be(true);
+                done.Wait(ALONGTIME_MS).Should().Be(true, because: "all tasks have to run");
             }
         }
 
@@ -48,7 +48,7 @@ public void ShouldScheduleAwaitableTask(RequestProcessType type)
                     await Task.Yield();
                     done.Signal();
                 });
-                done.Wait(ALONGTIME_MS).Should().Be(true);
+                done.Wait(ALONGTIME_MS).Should().Be(true, because: "all tasks have to run");
             }
         }
 
@@ -64,7 +64,7 @@ public void ShouldScheduleConstructedTask(RequestProcessType type)
                         done.Signal();
                     });
                 });
-                done.Wait(ALONGTIME_MS).Should().Be(true);
+                done.Wait(ALONGTIME_MS).Should().Be(true, because: "all tasks have to run");
             }
         }
 
@@ -89,9 +89,11 @@ public void ShouldScheduleSerialInOrder()
                 for (var i = 0; i < done.CurrentCount; i++)
                     s.Add(RequestProcessType.Serial, HandlePeek);
 
-                done.Wait(ALONGTIME_MS).Should().Be(true);
-                running.Should().Be(0);
-                peek.Should().Be(1);
+                done.Wait(ALONGTIME_MS).Should().Be(true, because: "all tasks have to run");
+                running.Should().Be(0, because: "all tasks have to run normally");
+                peek.Should().Be(1, because: "all tasks must not overlap");
+                s.Dispose();
+                Interlocked.Read(ref ((ProcessScheduler)s)._TestOnly_NonCompleteTaskCount).Should().Be(0, because: "the scheduler must not wait for tasks to complete after disposal");
             }
         }
 
@@ -116,9 +118,11 @@ public void ShouldScheduleParallelInParallel()
                 for (var i = 0; i<done.CurrentCount; i++)
                     s.Add(RequestProcessType.Parallel, HandlePeek);
 
-                done.Wait(ALONGTIME_MS).Should().Be(true);
-                running.Should().Be(0);
-                peek.Should().BeGreaterThan(3);
+                done.Wait(ALONGTIME_MS).Should().Be(true, because:"all tasks have to run");
+                running.Should().Be(0, because:"all tasks have to run normally");
+                peek.Should().BeGreaterThan(3, because:"a lot of tasks should overlap");
+                s.Dispose();
+                Interlocked.Read(ref ((ProcessScheduler)s)._TestOnly_NonCompleteTaskCount).Should().Be(0, because: "the scheduler must not wait for tasks to complete after disposal");
             }
         }
 
@@ -149,9 +153,11 @@ public void ShouldScheduleMixed()
                 s.Add(RequestProcessType.Parallel, HandlePeek);
                 s.Add(RequestProcessType.Serial, HandlePeek);
 
-                done.Wait(ALONGTIME_MS).Should().Be(true);
-                running.Should().Be(0);
-                peek.Should().BeGreaterThan(2);
+                done.Wait(ALONGTIME_MS).Should().Be(true, because: "all tasks have to run");
+                running.Should().Be(0, because: "all tasks have to run normally");
+                peek.Should().BeGreaterThan(2, because: "some tasks should overlap");
+                s.Dispose();
+                Interlocked.Read(ref ((ProcessScheduler)s)._TestOnly_NonCompleteTaskCount).Should().Be(0, because: "the scheduler must not wait for tasks to complete after disposal");
             }
         }
     }