docs: update TOC

.gitignore

@@ -213,3 +213,43 @@ src/UniTask/UniTask.Addressables.csproj
 src/UniTask/UniTask.DOTween.csproj
 
 src/UniTask/UniTask.TextMeshPro.csproj
+
+src/UniTask/RuntimeUnitTestToolkit.Player.csproj
+
+src/UniTask/TempAsm.Player.csproj
+
+src/UniTask/UniTask.Addressables.Player.csproj
+
+src/UniTask/UniTask.DOTween.Player.csproj
+
+src/UniTask/UniTask.Linq.Player.csproj
+
+src/UniTask/UniTask.Player.csproj
+
+src/UniTask/UniTask.Tests.Player.csproj
+
+src/UniTask/UniTask.TextMeshPro.Player.csproj
+
+src/UniTask/Unity.Addressables.Player.csproj
+
+src/UniTask/Unity.Analytics.DataPrivacy.Player.csproj
+
+src/UniTask/Unity.ResourceManager.Player.csproj
+
+src/UniTask/Unity.ScriptableBuildPipeline.Player.csproj
+
+src/UniTask/Unity.TextMeshPro.Player.csproj
+
+src/UniTask/Unity.Timeline.Player.csproj
+
+src/UniTask/UnityEngine.Advertisements.Player.csproj
+
+src/UniTask/UnityEngine.Monetization.Player.csproj
+
+src/UniTask/UnityEngine.TestRunner.Player.csproj
+
+src/UniTask/UnityEngine.UI.Player.csproj
+
+src/UniTask/DOTween.Modules.Player.csproj
+
+src/UniTask/Assembly-CSharp.Player.csproj

README.md

@@ -34,6 +34,7 @@ Techinical details, see blog post: [UniTask v2 — Zero Allocation async/await f
 - [For Unit Testing](#for-unit-testing)
 - [Compare with Standard Task API](#compare-with-standard-task-api)
 - [Pooling Configuration](#pooling-configuration)
+- [UniTaskSynchronizationContext](#unitasksynchronizationcontext)
 - [API References](#api-references)
 - [UPM Package](#upm-package)
   - [Install via git URL](#install-via-git-url)
@@ -384,6 +385,16 @@ var playerLoop = ScriptBehaviourUpdateOrder.CurrentPlayerLoop;
 PlayerLoopHelper.Initialize(ref playerLoop);
 ```
 
+You can diagnostic UniTask's player loop is ready by `PlayerLoopHelper.IsInjectedUniTaskPlayerLoop()`. And also `PlayerLoopHelper.DumpCurrentPlayerLoop` shows current all playerloop to console.
+
+```csharp
+void Start()
+{
+    UnityEngine.Debug.Log("UniTaskPlayerLoop ready? " + PlayerLoopHelper.IsInjectedUniTaskPlayerLoop());
+    PlayerLoopHelper.DumpCurrentPlayerLoop();
+}
+```
+
 async void vs async UniTaskVoid
 ---
 `async void` is a standard C# task system so does not run on UniTask systems. It is better not to use. `async UniTaskVoid` is a lightweight version of `async UniTask` because it does not have awaitable completion and report error immediately to `UniTaskScheduler.UnobservedTaskException`. If you don't require to await it(fire and forget), use `UniTaskVoid` is better. Unfortunately to dismiss warning, require to using with `Forget()`.
@@ -826,6 +837,23 @@ foreach (var (type, size) in TaskPool.GetCacheSizeInfo())
 
 > In UnityEditor profiler shows allocation of compiler generated AsyncStateMachine but it only occurs in debug(development) build. C# Compiler generate AsyncStateMachine as class on Debug build and as struct on Release build.
 
+UniTaskSynchronizationContext
+---
+Unity's default SynchronizationContext(`UnitySynchronizationContext`) is poor implementation for performance. UniTask itself is bypass `SynchronizationContext`(and `ExecutionContext`) so does not use it but if exists in `async Task`, still used it. `UniTaskSynchronizationContext` is replacement of `UnitySynchronizationContext`, it is better for performance.
+
+```csharp
+public class SyncContextInjecter
+{
+    [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
+    public static void Inject()
+    {
+        SynchronizationContext.SetSynchronizationContext(new UniTaskSynchronizationContext());
+    }
+}
+```
+
+This is an optional choice and is not always recommended; `UniTaskSynchronizationContext` is less performance than `async UniTask` and is not a complete UniTask replacement. It also does not guarantee full behavioral compatibility with the `UnitySynchronizationContext`.
+
 API References
 ---
 UniTask's API References is hosted at [cysharp.github.io/UniTask](https://cysharp.github.io/UniTask/api/Cysharp.Threading.Tasks.html) by [DocFX](https://dotnet.github.io/docfx/) and [Cysharp/DocfXTemplate](https://github.com/Cysharp/DocfxTemplate).

src/UniTask.NetCore/UniTask.NetCore.csproj

@@ -38,6 +38,7 @@
 ..\UniTask\Assets\Plugins\UniTask\Runtime\Internal\ContinuationQueue.cs;
 ..\UniTask\Assets\Plugins\UniTask\Runtime\Internal\UnityWebRequestExtensions.cs;
   
+..\UniTask\Assets\Plugins\UniTask\Runtime\UniTaskSynchronizationContext.cs;
 ..\UniTask\Assets\Plugins\UniTask\Runtime\CancellationTokenSourceExtensions.cs;
 ..\UniTask\Assets\Plugins\UniTask\Runtime\EnumeratorAsyncExtensions.cs;
 ..\UniTask\Assets\Plugins\UniTask\Runtime\PlayerLoopHelper.cs;

src/UniTask.NetCoreTests/WithCancellationTest.cs

@@ -0,0 +1,40 @@
+using Cysharp.Threading.Tasks;
+using FluentAssertions;
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace NetCoreTests
+{
+    public class WithCancellationTest
+    {
+        [Fact]
+        public async Task Standard()
+        {
+            CancellationTokenSource cts = new CancellationTokenSource();
+
+            var v = await UniTask.Run(() => 10).WithCancellation(cts.Token);
+
+            v.Should().Be(10);
+        }
+
+        [Fact]
+        public async Task Cancel()
+        {
+            CancellationTokenSource cts = new CancellationTokenSource();
+
+            var t = UniTask.Create(async () =>
+            {
+                await Task.Delay(TimeSpan.FromSeconds(1));
+                return 10;
+            }).WithCancellation(cts.Token);
+
+            cts.Cancel();
+
+            (await Assert.ThrowsAsync<OperationCanceledException>(async () => await t)).CancellationToken.Should().Be(cts.Token);
+        }
+    }
+}

src/UniTask/Assets/Plugins/UniTask/Runtime/External/Addressables/AddressablesAsyncExtensions.cs

@@ -15,29 +15,25 @@ namespace Cysharp.Threading.Tasks
     {
         #region AsyncOperationHandle
 
-        public static AsyncOperationHandleAwaiter GetAwaiter(this AsyncOperationHandle handle)
+        public static UniTask.Awaiter GetAwaiter(this AsyncOperationHandle handle)
         {
-            return new AsyncOperationHandleAwaiter(handle);
+            return ToUniTask(handle).GetAwaiter();
         }
 
         public static UniTask WithCancellation(this AsyncOperationHandle handle, CancellationToken cancellationToken)
         {
-            if (cancellationToken.IsCancellationRequested) return UniTask.FromCanceled(cancellationToken);
-            if (handle.IsDone)
-            {
-                if (handle.Status == AsyncOperationStatus.Failed)
-                {
-                    return UniTask.FromException(handle.OperationException);
-                }
-                return UniTask.CompletedTask;
-            }
-
-            return new UniTask(AsyncOperationHandleWithCancellationSource.Create(handle, cancellationToken, out var token), token);
+            return ToUniTask(handle, cancellationToken: cancellationToken);
         }
 
         public static UniTask ToUniTask(this AsyncOperationHandle handle, IProgress<float> progress = null, PlayerLoopTiming timing = PlayerLoopTiming.Update, CancellationToken cancellationToken = default(CancellationToken))
         {
             if (cancellationToken.IsCancellationRequested) return UniTask.FromCanceled(cancellationToken);
+
+            if (!handle.IsValid())
+            {
+                throw new Exception("Attempting to use an invalid operation handle");
+            }
+
             if (handle.IsDone)
             {
                 if (handle.Status == AsyncOperationStatus.Failed)
@@ -95,29 +91,30 @@ namespace Cysharp.Threading.Tasks
             }
         }
 
-        sealed class AsyncOperationHandleWithCancellationSource : IUniTaskSource, IPlayerLoopItem, ITaskPoolNode<AsyncOperationHandleWithCancellationSource>
+        sealed class AsyncOperationHandleConfiguredSource : IUniTaskSource, IPlayerLoopItem, ITaskPoolNode<AsyncOperationHandleConfiguredSource>
         {
-            static TaskPool<AsyncOperationHandleWithCancellationSource> pool;
-            public AsyncOperationHandleWithCancellationSource NextNode { get; set; }
+            static TaskPool<AsyncOperationHandleConfiguredSource> pool;
+            public AsyncOperationHandleConfiguredSource NextNode { get; set; }
 
-            static AsyncOperationHandleWithCancellationSource()
+            static AsyncOperationHandleConfiguredSource()
             {
-                TaskPool.RegisterSizeGetter(typeof(AsyncOperationHandleWithCancellationSource), () => pool.Size);
+                TaskPool.RegisterSizeGetter(typeof(AsyncOperationHandleConfiguredSource), () => pool.Size);
             }
 
             readonly Action<AsyncOperationHandle> continuationAction;
             AsyncOperationHandle handle;
             CancellationToken cancellationToken;
+            IProgress<float> progress;
             bool completed;
 
             UniTaskCompletionSourceCore<AsyncUnit> core;
 
-            AsyncOperationHandleWithCancellationSource()
+            AsyncOperationHandleConfiguredSource()
             {
                 continuationAction = Continuation;
             }
 
-            public static IUniTaskSource Create(AsyncOperationHandle handle, CancellationToken cancellationToken, out short token)
+            public static IUniTaskSource Create(AsyncOperationHandle handle, PlayerLoopTiming timing, IProgress<float> progress, CancellationToken cancellationToken, out short token)
             {
                 if (cancellationToken.IsCancellationRequested)
                 {
@@ -126,16 +123,17 @@ namespace Cysharp.Threading.Tasks
 
                 if (!pool.TryPop(out var result))
                 {
-                    result = new AsyncOperationHandleWithCancellationSource();
+                    result = new AsyncOperationHandleConfiguredSource();
                 }
 
                 result.handle = handle;
+                result.progress = progress;
                 result.cancellationToken = cancellationToken;
                 result.completed = false;
 
                 TaskTracker.TrackActiveTask(result, 3);
 
-                PlayerLoopHelper.AddAction(PlayerLoopTiming.Update, result);
+                PlayerLoopHelper.AddAction(timing, result);
 
                 handle.Completed += result.continuationAction;
 
@@ -204,125 +202,18 @@ namespace Cysharp.Threading.Tasks
                     return false;
                 }
 
-                return true;
-            }
-
-            bool TryReturn()
-            {
-                TaskTracker.RemoveTracking(this);
-                core.Reset();
-                handle = default;
-                cancellationToken = default;
-                return pool.TryPush(this);
-            }
-        }
-
-        sealed class AsyncOperationHandleConfiguredSource : IUniTaskSource, IPlayerLoopItem, ITaskPoolNode<AsyncOperationHandleConfiguredSource>
-        {
-            static TaskPool<AsyncOperationHandleConfiguredSource> pool;
-            public AsyncOperationHandleConfiguredSource NextNode { get; set; }
-
-            static AsyncOperationHandleConfiguredSource()
-            {
-                TaskPool.RegisterSizeGetter(typeof(AsyncOperationHandleConfiguredSource), () => pool.Size);
-            }
-
-            AsyncOperationHandle handle;
-            IProgress<float> progress;
-            CancellationToken cancellationToken;
-
-            UniTaskCompletionSourceCore<AsyncUnit> core;
-
-            AsyncOperationHandleConfiguredSource()
-            {
-
-            }
-
-            public static IUniTaskSource Create(AsyncOperationHandle handle, PlayerLoopTiming timing, IProgress<float> progress, CancellationToken cancellationToken, out short token)
-            {
-                if (cancellationToken.IsCancellationRequested)
-                {
-                    return AutoResetUniTaskCompletionSource.CreateFromCanceled(cancellationToken, out token);
-                }
-
-                if (!pool.TryPop(out var result))
-                {
-                    result = new AsyncOperationHandleConfiguredSource();
-                }
-
-                result.handle = handle;
-                result.progress = progress;
-                result.cancellationToken = cancellationToken;
-
-                TaskTracker.TrackActiveTask(result, 3);
-
-                PlayerLoopHelper.AddAction(timing, result);
-
-                token = result.core.Version;
-                return result;
-            }
-
-            public void GetResult(short token)
-            {
-                try
-                {
-
-                    core.GetResult(token);
-                }
-                finally
-                {
-                    TryReturn();
-                }
-            }
-
-            public UniTaskStatus GetStatus(short token)
-            {
-                return core.GetStatus(token);
-            }
-
-            public UniTaskStatus UnsafeGetStatus()
-            {
-                return core.UnsafeGetStatus();
-            }
-
-            public void OnCompleted(Action<object> continuation, object state, short token)
-            {
-                core.OnCompleted(continuation, state, token);
-            }
-
-            public bool MoveNext()
-            {
-                if (cancellationToken.IsCancellationRequested)
-                {
-                    core.TrySetCanceled(cancellationToken);
-                    return false;
-                }
-
-                if (progress != null)
+                if (progress != null && handle.IsValid())
                 {
                     progress.Report(handle.PercentComplete);
                 }
 
-                if (handle.IsDone)
-                {
-                    if (handle.Status == AsyncOperationStatus.Failed)
-                    {
-                        core.TrySetException(handle.OperationException);
-                    }
-                    else
-                    {
-                        core.TrySetResult(AsyncUnit.Default);
-                    }
-                    return false;
-                }
-
                 return true;
             }
 
             bool TryReturn()
             {
-                core.Reset();
                 TaskTracker.RemoveTracking(this);
+                core.Reset();
                 handle = default;
                 progress = default;
                 cancellationToken = default;
@@ -334,28 +225,25 @@ namespace Cysharp.Threading.Tasks
 
         #region AsyncOperationHandle_T
 
-        public static AsyncOperationHandleAwaiter<T> GetAwaiter<T>(this AsyncOperationHandle<T> handle)
+        public static UniTask<T>.Awaiter GetAwaiter<T>(this AsyncOperationHandle<T> handle)
         {
-            return new AsyncOperationHandleAwaiter<T>(handle);
+            return ToUniTask(handle).GetAwaiter();
         }
 
         public static UniTask<T> WithCancellation<T>(this AsyncOperationHandle<T> handle, CancellationToken cancellationToken)
         {
-            if (cancellationToken.IsCancellationRequested) return UniTask.FromCanceled<T>(cancellationToken);
-            if (handle.IsDone)
-            {
-                if (handle.Status == AsyncOperationStatus.Failed)
-                {
-                    return UniTask.FromException<T>(handle.OperationException);
-                }
-                return UniTask.FromResult(handle.Result);
-            }
-            return new UniTask<T>(AsyncOperationHandleWithCancellationSource<T>.Create(handle, cancellationToken, out var token), token);
+            return ToUniTask(handle, cancellationToken: cancellationToken);
         }
 
         public static UniTask<T> ToUniTask<T>(this AsyncOperationHandle<T> handle, IProgress<float> progress = null, PlayerLoopTiming timing = PlayerLoopTiming.Update, CancellationToken cancellationToken = default(CancellationToken))
         {
             if (cancellationToken.IsCancellationRequested) return UniTask.FromCanceled<T>(cancellationToken);
+
+            if (!handle.IsValid())
+            {
+                throw new Exception("Attempting to use an invalid operation handle");
+            }
+
             if (handle.IsDone)
             {
                 if (handle.Status == AsyncOperationStatus.Failed)
@@ -368,75 +256,30 @@ namespace Cysharp.Threading.Tasks
             return new UniTask<T>(AsyncOperationHandleConfiguredSource<T>.Create(handle, timing, progress, cancellationToken, out var token), token);
         }
 
-        public struct AsyncOperationHandleAwaiter<T> : ICriticalNotifyCompletion
+        sealed class AsyncOperationHandleConfiguredSource<T> : IUniTaskSource<T>, IPlayerLoopItem, ITaskPoolNode<AsyncOperationHandleConfiguredSource<T>>
         {
-            AsyncOperationHandle<T> handle;
-            Action<AsyncOperationHandle> continuationAction;
+            static TaskPool<AsyncOperationHandleConfiguredSource<T>> pool;
+            public AsyncOperationHandleConfiguredSource<T> NextNode { get; set; }
 
-            public AsyncOperationHandleAwaiter(AsyncOperationHandle<T> handle)
+            static AsyncOperationHandleConfiguredSource()
             {
-                this.handle = handle;
-                this.continuationAction = null;
-            }
-
-            public bool IsCompleted => handle.IsDone;
-
-            public T GetResult()
-            {
-                if (continuationAction != null)
-                {
-                    handle.CompletedTypeless -= continuationAction;
-                    continuationAction = null;
-                }
-
-                if (handle.Status == AsyncOperationStatus.Failed)
-                {
-                    var e = handle.OperationException;
-                    handle = default;
-                    ExceptionDispatchInfo.Capture(e).Throw();
-                }
-
-                var result = handle.Result;
-                handle = default;
-                return result;
-            }
-
-            public void OnCompleted(Action continuation)
-            {
-                UnsafeOnCompleted(continuation);
-            }
-
-            public void UnsafeOnCompleted(Action continuation)
-            {
-                Error.ThrowWhenContinuationIsAlreadyRegistered(continuationAction);
-                continuationAction = PooledDelegate<AsyncOperationHandle>.Create(continuation);
-                handle.CompletedTypeless += continuationAction;
-            }
-        }
-
-        sealed class AsyncOperationHandleWithCancellationSource<T> : IUniTaskSource<T>, IPlayerLoopItem, ITaskPoolNode<AsyncOperationHandleWithCancellationSource<T>>
-        {
-            static TaskPool<AsyncOperationHandleWithCancellationSource<T>> pool;
-            public AsyncOperationHandleWithCancellationSource<T> NextNode { get; set; }
-
-            static AsyncOperationHandleWithCancellationSource()
-            {
-                TaskPool.RegisterSizeGetter(typeof(AsyncOperationHandleWithCancellationSource<T>), () => pool.Size);
+                TaskPool.RegisterSizeGetter(typeof(AsyncOperationHandleConfiguredSource<T>), () => pool.Size);
             }
 
             readonly Action<AsyncOperationHandle<T>> continuationAction;
             AsyncOperationHandle<T> handle;
             CancellationToken cancellationToken;
+            IProgress<float> progress;
             bool completed;
 
             UniTaskCompletionSourceCore<T> core;
 
-            AsyncOperationHandleWithCancellationSource()
+            AsyncOperationHandleConfiguredSource()
             {
                 continuationAction = Continuation;
             }
 
-            public static IUniTaskSource<T> Create(AsyncOperationHandle<T> handle, CancellationToken cancellationToken, out short token)
+            public static IUniTaskSource<T> Create(AsyncOperationHandle<T> handle, PlayerLoopTiming timing, IProgress<float> progress, CancellationToken cancellationToken, out short token)
             {
                 if (cancellationToken.IsCancellationRequested)
                 {
@@ -445,16 +288,17 @@ namespace Cysharp.Threading.Tasks
 
                 if (!pool.TryPop(out var result))
                 {
-                    result = new AsyncOperationHandleWithCancellationSource<T>();
+                    result = new AsyncOperationHandleConfiguredSource<T>();
                 }
 
                 result.handle = handle;
                 result.cancellationToken = cancellationToken;
                 result.completed = false;
+                result.progress = progress;
 
                 TaskTracker.TrackActiveTask(result, 3);
 
-                PlayerLoopHelper.AddAction(PlayerLoopTiming.Update, result);
+                PlayerLoopHelper.AddAction(timing, result);
 
                 handle.Completed += result.continuationAction;
 
@@ -462,7 +306,7 @@ namespace Cysharp.Threading.Tasks
                 return result;
             }
 
-            void Continuation(AsyncOperationHandle<T> _)
+            void Continuation(AsyncOperationHandle<T> argHandle)
             {
                 handle.Completed -= continuationAction;
 
@@ -477,13 +321,13 @@ namespace Cysharp.Threading.Tasks
                     {
                         core.TrySetCanceled(cancellationToken);
                     }
-                    else if (handle.Status == AsyncOperationStatus.Failed)
+                    else if (argHandle.Status == AsyncOperationStatus.Failed)
                     {
-                        core.TrySetException(handle.OperationException);
+                        core.TrySetException(argHandle.OperationException);
                     }
                     else
                     {
-                        core.TrySetResult(handle.Result);
+                        core.TrySetResult(argHandle.Result);
                     }
                 }
             }
@@ -528,122 +372,11 @@ namespace Cysharp.Threading.Tasks
                     return false;
                 }
 
-                return true;
-            }
-
-            bool TryReturn()
-            {
-                TaskTracker.RemoveTracking(this);
-                core.Reset();
-                handle = default;
-                cancellationToken = default;
-                return pool.TryPush(this);
-            }
-        }
-
-        sealed class AsyncOperationHandleConfiguredSource<T> : IUniTaskSource<T>, IPlayerLoopItem, ITaskPoolNode<AsyncOperationHandleConfiguredSource<T>>
-        {
-            static TaskPool<AsyncOperationHandleConfiguredSource<T>> pool;
-            public AsyncOperationHandleConfiguredSource<T> NextNode { get; set; }
-
-            static AsyncOperationHandleConfiguredSource()
-            {
-                TaskPool.RegisterSizeGetter(typeof(AsyncOperationHandleConfiguredSource<T>), () => pool.Size);
-            }
-
-            AsyncOperationHandle<T> handle;
-            IProgress<float> progress;
-            CancellationToken cancellationToken;
-
-            UniTaskCompletionSourceCore<T> core;
-
-            AsyncOperationHandleConfiguredSource()
-            {
-
-            }
-
-            public static IUniTaskSource<T> Create(AsyncOperationHandle<T> handle, PlayerLoopTiming timing, IProgress<float> progress, CancellationToken cancellationToken, out short token)
-            {
-                if (cancellationToken.IsCancellationRequested)
-                {
-                    return AutoResetUniTaskCompletionSource<T>.CreateFromCanceled(cancellationToken, out token);
-                }
-
-                if (!pool.TryPop(out var result))
-                {
-                    result = new AsyncOperationHandleConfiguredSource<T>();
-                }
-
-                result.handle = handle;
-                result.progress = progress;
-                result.cancellationToken = cancellationToken;
-
-                TaskTracker.TrackActiveTask(result, 3);
-
-                PlayerLoopHelper.AddAction(timing, result);
-
-                token = result.core.Version;
-                return result;
-            }
-
-            public T GetResult(short token)
-            {
-                try
-                {
-                    return core.GetResult(token);
-                }
-                finally
-                {
-                    TryReturn();
-                }
-            }
-
-            void IUniTaskSource.GetResult(short token)
-            {
-                GetResult(token);
-            }
-
-            public UniTaskStatus GetStatus(short token)
-            {
-                return core.GetStatus(token);
-            }
-
-            public UniTaskStatus UnsafeGetStatus()
-            {
-                return core.UnsafeGetStatus();
-            }
-
-            public void OnCompleted(Action<object> continuation, object state, short token)
-            {
-                core.OnCompleted(continuation, state, token);
-            }
-
-            public bool MoveNext()
-            {
-                if (cancellationToken.IsCancellationRequested)
-                {
-                    core.TrySetCanceled(cancellationToken);
-                    return false;
-                }
-
-                if (progress != null)
+                if (progress != null && handle.IsValid())
                 {
                     progress.Report(handle.PercentComplete);
                 }
 
-                if (handle.IsDone)
-                {
-                    if (handle.Status == AsyncOperationStatus.Failed)
-                    {
-                        core.TrySetException(handle.OperationException);
-                    }
-                    else
-                    {
-                        core.TrySetResult(handle.Result);
-                    }
-                    return false;
-                }
-
                 return true;
             }
 

src/UniTask/Assets/Plugins/UniTask/Runtime/PlayerLoopHelper.cs

@@ -175,6 +175,32 @@ namespace Cysharp.Threading.Tasks
             return dest;
         }
 
+        static PlayerLoopSystem[] InsertUniTaskSynchronizationContext(PlayerLoopSystem loopSystem)
+        {
+            var loop = new PlayerLoopSystem
+            {
+                type = typeof(UniTaskSynchronizationContext),
+                updateDelegate = UniTaskSynchronizationContext.Run
+            };
+
+            // Remove items from previous initializations.
+            var source = loopSystem.subSystemList
+                .Where(ls => ls.type != typeof(UniTaskSynchronizationContext))
+                .ToArray();
+
+            var dest = new System.Collections.Generic.List<PlayerLoopSystem>(source);
+
+            var index = dest.FindIndex(x => x.type.Name == "ScriptRunDelayedTasks");
+            if (index == -1)
+            {
+                index = dest.FindIndex(x => x.type.Name == "UniTaskLoopRunnerUpdate");
+            }
+
+            dest.Insert(index + 1, loop);
+
+            return dest.ToArray();
+        }
+
         [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.BeforeSceneLoad)]
         static void Init()
         {
@@ -246,6 +272,8 @@ namespace Cysharp.Threading.Tasks
                     if (item != null) item.Run();
                 }
             }
+
+            UniTaskSynchronizationContext.Run();
         }
 
 #endif
@@ -293,6 +321,9 @@ namespace Cysharp.Threading.Tasks
                                                                   typeof(UniTaskLoopRunners.UniTaskLoopRunnerPostLateUpdate), runners[12] = new PlayerLoopRunner(PlayerLoopTiming.PostLateUpdate),
                                                                   typeof(UniTaskLoopRunners.UniTaskLoopRunnerLastPostLateUpdate), runners[13] = new PlayerLoopRunner(PlayerLoopTiming.LastPostLateUpdate));
 
+            // Insert UniTaskSynchronizationContext to Update loop
+            copyList[4].subSystemList = InsertUniTaskSynchronizationContext(copyList[4]);
+
             playerLoop.subSystemList = copyList;
             PlayerLoop.SetPlayerLoop(playerLoop);
         }
@@ -306,6 +337,56 @@ namespace Cysharp.Threading.Tasks
         {
             yielders[(int)timing].Enqueue(continuation);
         }
+
+        // Diagnostics helper
+
+#if UNITY_2019_3_OR_NEWER
+
+        public static void DumpCurrentPlayerLoop()
+        {
+            var playerLoop = UnityEngine.LowLevel.PlayerLoop.GetCurrentPlayerLoop();
+
+            var sb = new System.Text.StringBuilder();
+            sb.AppendLine($"PlayerLoop List");
+            foreach (var header in playerLoop.subSystemList)
+            {
+                sb.AppendFormat("------{0}------", header.type.Name);
+                sb.AppendLine();
+                foreach (var subSystem in header.subSystemList)
+                {
+                    sb.AppendFormat("{0}", subSystem.type.Name);
+                    sb.AppendLine();
+
+                    if (subSystem.subSystemList != null)
+                    {
+                        UnityEngine.Debug.LogWarning("More Subsystem:" + subSystem.subSystemList.Length);
+                    }
+                }
+            }
+
+            UnityEngine.Debug.Log(sb.ToString());
+        }
+
+        public static bool IsInjectedUniTaskPlayerLoop()
+        {
+            var playerLoop = UnityEngine.LowLevel.PlayerLoop.GetCurrentPlayerLoop();
+
+            foreach (var header in playerLoop.subSystemList)
+            {
+                foreach (var subSystem in header.subSystemList)
+                {
+                    if (subSystem.type == typeof(UniTaskLoopRunners.UniTaskLoopRunnerInitialization))
+                    {
+                        return true;
+                    }
+                }
+            }
+
+            return false;
+        }
+
+#endif
+
     }
 }
 

src/UniTask/Assets/Plugins/UniTask/Runtime/UniTaskExtensions.cs

@@ -189,6 +189,174 @@ namespace Cysharp.Threading.Tasks
             return new AsyncLazy<T>(task);
         }
 
+        /// <summary>
+        /// Ignore task result when cancel raised first.
+        /// </summary>
+        public static UniTask WithCancellation(this UniTask task, CancellationToken cancellationToken)
+        {
+            if (!cancellationToken.CanBeCanceled)
+            {
+                return task;
+            }
+
+            if (cancellationToken.IsCancellationRequested)
+            {
+                return UniTask.FromCanceled(cancellationToken);
+            }
+
+            if (task.Status.IsCompleted())
+            {
+                return task;
+            }
+
+            return new UniTask(new WithCancellationSource(task, cancellationToken), 0);
+        }
+
+        /// <summary>
+        /// Ignore task result when cancel raised first.
+        /// </summary>
+        public static UniTask<T> WithCancellation<T>(this UniTask<T> task, CancellationToken cancellationToken)
+        {
+            if (!cancellationToken.CanBeCanceled)
+            {
+                return task;
+            }
+
+            if (cancellationToken.IsCancellationRequested)
+            {
+                return UniTask.FromCanceled<T>(cancellationToken);
+            }
+
+            if (task.Status.IsCompleted())
+            {
+                return task;
+            }
+
+            return new UniTask<T>(new WithCancellationSource<T>(task, cancellationToken), 0);
+        }
+
+        sealed class WithCancellationSource : IUniTaskSource
+        {
+            static readonly Action<object> cancellationCallbackDelegate = CancellationCallback;
+
+            CancellationToken cancellationToken;
+            CancellationTokenRegistration tokenRegistration;
+            UniTaskCompletionSourceCore<AsyncUnit> core;
+
+            public WithCancellationSource(UniTask task, CancellationToken cancellationToken)
+            {
+                this.cancellationToken = cancellationToken;
+                this.tokenRegistration = cancellationToken.RegisterWithoutCaptureExecutionContext(cancellationCallbackDelegate, this);
+                RunTask(task).Forget();
+            }
+
+            async UniTaskVoid RunTask(UniTask task)
+            {
+                try
+                {
+                    await task;
+                    core.TrySetResult(AsyncUnit.Default);
+                }
+                catch (Exception ex)
+                {
+                    core.TrySetException(ex);
+                }
+                finally
+                {
+                    tokenRegistration.Dispose();
+                }
+            }
+
+            static void CancellationCallback(object state)
+            {
+                var self = (WithCancellationSource)state;
+                self.core.TrySetCanceled(self.cancellationToken);
+            }
+
+            public void GetResult(short token)
+            {
+                core.GetResult(token);
+            }
+
+            public UniTaskStatus GetStatus(short token)
+            {
+                return core.GetStatus(token);
+            }
+
+            public void OnCompleted(Action<object> continuation, object state, short token)
+            {
+                core.OnCompleted(continuation, state, token);
+            }
+
+            public UniTaskStatus UnsafeGetStatus()
+            {
+                return core.UnsafeGetStatus();
+            }
+        }
+
+        sealed class WithCancellationSource<T> : IUniTaskSource<T>
+        {
+            static readonly Action<object> cancellationCallbackDelegate = CancellationCallback;
+
+            CancellationToken cancellationToken;
+            CancellationTokenRegistration tokenRegistration;
+            UniTaskCompletionSourceCore<T> core;
+
+            public WithCancellationSource(UniTask<T> task, CancellationToken cancellationToken)
+            {
+                this.cancellationToken = cancellationToken;
+                this.tokenRegistration = cancellationToken.RegisterWithoutCaptureExecutionContext(cancellationCallbackDelegate, this);
+                RunTask(task).Forget();
+            }
+
+            async UniTaskVoid RunTask(UniTask<T> task)
+            {
+                try
+                {
+                    core.TrySetResult(await task);
+                }
+                catch (Exception ex)
+                {
+                    core.TrySetException(ex);
+                }
+                finally
+                {
+                    tokenRegistration.Dispose();
+                }
+            }
+
+            static void CancellationCallback(object state)
+            {
+                var self = (WithCancellationSource<T>)state;
+                self.core.TrySetCanceled(self.cancellationToken);
+            }
+
+            void IUniTaskSource.GetResult(short token)
+            {
+                core.GetResult(token);
+            }
+
+            public T GetResult(short token)
+            {
+                return core.GetResult(token);
+            }
+
+            public UniTaskStatus GetStatus(short token)
+            {
+                return core.GetStatus(token);
+            }
+
+            public void OnCompleted(Action<object> continuation, object state, short token)
+            {
+                core.OnCompleted(continuation, state, token);
+            }
+
+            public UniTaskStatus UnsafeGetStatus()
+            {
+                return core.UnsafeGetStatus();
+            }
+        }
+
 #if UNITY_2018_3_OR_NEWER
 
         public static IEnumerator ToCoroutine<T>(this UniTask<T> task, Action<T> resultHandler = null, Action<Exception> exceptionHandler = null)

src/UniTask/Assets/Plugins/UniTask/Runtime/UniTaskSynchronizationContext.cs

@@ -0,0 +1,158 @@
+using System;
+using System.Runtime.InteropServices;
+using System.Threading;
+
+namespace Cysharp.Threading.Tasks
+{
+    public class UniTaskSynchronizationContext : SynchronizationContext
+    {
+        const int MaxArrayLength = 0X7FEFFFFF;
+        const int InitialSize = 16;
+
+        static SpinLock gate = new SpinLock();
+        static bool dequing = false;
+
+        static int actionListCount = 0;
+        static Callback[] actionList = new Callback[InitialSize];
+
+        static int waitingListCount = 0;
+        static Callback[] waitingList = new Callback[InitialSize];
+
+        static int opCount;
+
+        public override void Send(SendOrPostCallback d, object state)
+        {
+            d(state);
+        }
+
+        public override void Post(SendOrPostCallback d, object state)
+        {
+            bool lockTaken = false;
+            try
+            {
+                gate.Enter(ref lockTaken);
+
+                if (dequing)
+                {
+                    // Ensure Capacity
+                    if (waitingList.Length == waitingListCount)
+                    {
+                        var newLength = waitingListCount * 2;
+                        if ((uint)newLength > MaxArrayLength) newLength = MaxArrayLength;
+
+                        var newArray = new Callback[newLength];
+                        Array.Copy(waitingList, newArray, waitingListCount);
+                        waitingList = newArray;
+                    }
+                    waitingList[waitingListCount] = new Callback(d, state);
+                    waitingListCount++;
+                }
+                else
+                {
+                    // Ensure Capacity
+                    if (actionList.Length == actionListCount)
+                    {
+                        var newLength = actionListCount * 2;
+                        if ((uint)newLength > MaxArrayLength) newLength = MaxArrayLength;
+
+                        var newArray = new Callback[newLength];
+                        Array.Copy(actionList, newArray, actionListCount);
+                        actionList = newArray;
+                    }
+                    actionList[actionListCount] = new Callback(d, state);
+                    actionListCount++;
+                }
+            }
+            finally
+            {
+                if (lockTaken) gate.Exit(false);
+            }
+        }
+
+        public override void OperationStarted()
+        {
+            Interlocked.Increment(ref opCount);
+        }
+
+        public override void OperationCompleted()
+        {
+            Interlocked.Decrement(ref opCount);
+        }
+
+        public override SynchronizationContext CreateCopy()
+        {
+            return this;
+        }
+
+        // delegate entrypoint.
+        internal static void Run()
+        {
+            {
+                bool lockTaken = false;
+                try
+                {
+                    gate.Enter(ref lockTaken);
+                    if (actionListCount == 0) return;
+                    dequing = true;
+                }
+                finally
+                {
+                    if (lockTaken) gate.Exit(false);
+                }
+            }
+
+            for (int i = 0; i < actionListCount; i++)
+            {
+                var action = actionList[i];
+                actionList[i] = default;
+                action.Invoke();
+            }
+
+            {
+                bool lockTaken = false;
+                try
+                {
+                    gate.Enter(ref lockTaken);
+                    dequing = false;
+
+                    var swapTempActionList = actionList;
+
+                    actionListCount = waitingListCount;
+                    actionList = waitingList;
+
+                    waitingListCount = 0;
+                    waitingList = swapTempActionList;
+                }
+                finally
+                {
+                    if (lockTaken) gate.Exit(false);
+                }
+            }
+        }
+
+        [StructLayout(LayoutKind.Auto)]
+        readonly struct Callback
+        {
+            readonly SendOrPostCallback callback;
+            readonly object state;
+
+            public Callback(SendOrPostCallback callback, object state)
+            {
+                this.callback = callback;
+                this.state = state;
+            }
+
+            public void Invoke()
+            {
+                try
+                {
+                    callback(state);
+                }
+                catch (Exception ex)
+                {
+                    UnityEngine.Debug.LogException(ex);
+                }
+            }
+        }
+    }
+}

src/UniTask/Assets/Plugins/UniTask/Runtime/UniTaskSynchronizationContext.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: abf3aae9813db2849bce518f8596e920
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.AssetBundleRequestAllAssets.cs

@@ -0,0 +1,315 @@
+#pragma warning disable CS1591 // Missing XML comment for publicly visible type or member
+
+#if UNITY_2018_4 || UNITY_2019_4_OR_NEWER
+
+using Cysharp.Threading.Tasks.Internal;
+using System;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using UnityEngine;
+
+namespace Cysharp.Threading.Tasks
+{
+    public static partial class UnityAsyncExtensions
+    {
+        public static AssetBundleRequestAllAssetsAwaiter AwaitForAllAssets(this AssetBundleRequest asyncOperation)
+        {
+            Error.ThrowArgumentNullException(asyncOperation, nameof(asyncOperation));
+            return new AssetBundleRequestAllAssetsAwaiter(asyncOperation);
+        }
+
+        public static UniTask<UnityEngine.Object[]> AwaitForAllAssets(this AssetBundleRequest asyncOperation, CancellationToken cancellationToken)
+        {
+            Error.ThrowArgumentNullException(asyncOperation, nameof(asyncOperation));
+            if (cancellationToken.IsCancellationRequested) return UniTask.FromCanceled<UnityEngine.Object[]>(cancellationToken);
+            if (asyncOperation.isDone) return UniTask.FromResult<UnityEngine.Object[]>(asyncOperation.allAssets);
+            return new UniTask<UnityEngine.Object[]>(AssetBundleRequestAllAssetsWithCancellationSource.Create(asyncOperation, cancellationToken, out var token), token);
+        }
+
+        public static UniTask<UnityEngine.Object[]> AwaitForAllAssets(this AssetBundleRequest asyncOperation, IProgress<float> progress = null, PlayerLoopTiming timing = PlayerLoopTiming.Update, CancellationToken cancellationToken = default(CancellationToken))
+        {
+            Error.ThrowArgumentNullException(asyncOperation, nameof(asyncOperation));
+            if (cancellationToken.IsCancellationRequested) return UniTask.FromCanceled<UnityEngine.Object[]>(cancellationToken);
+            if (asyncOperation.isDone) return UniTask.FromResult(asyncOperation.allAssets);
+            return new UniTask<UnityEngine.Object[]>(AssetBundleRequestAllAssetsConfiguredSource.Create(asyncOperation, timing, progress, cancellationToken, out var token), token);
+        }
+
+        public struct AssetBundleRequestAllAssetsAwaiter : ICriticalNotifyCompletion
+        {
+            AssetBundleRequest asyncOperation;
+            Action<AsyncOperation> continuationAction;
+
+            public AssetBundleRequestAllAssetsAwaiter(AssetBundleRequest asyncOperation)
+            {
+                this.asyncOperation = asyncOperation;
+                this.continuationAction = null;
+            }
+
+            public bool IsCompleted => asyncOperation.isDone;
+
+            public UnityEngine.Object[] GetResult()
+            {
+                if (continuationAction != null)
+                {
+                    asyncOperation.completed -= continuationAction;
+                    continuationAction = null;
+                    var result = asyncOperation.allAssets;
+                    asyncOperation = null;
+                    return result;
+                }
+                else
+                {
+                    var result = asyncOperation.allAssets;
+                    asyncOperation = null;
+                    return result;
+                }
+            }
+
+            public void OnCompleted(Action continuation)
+            {
+                UnsafeOnCompleted(continuation);
+            }
+
+            public void UnsafeOnCompleted(Action continuation)
+            {
+                Error.ThrowWhenContinuationIsAlreadyRegistered(continuationAction);
+                continuationAction = PooledDelegate<AsyncOperation>.Create(continuation);
+                asyncOperation.completed += continuationAction;
+            }
+        }
+
+        sealed class AssetBundleRequestAllAssetsWithCancellationSource : IUniTaskSource<UnityEngine.Object[]>, IPlayerLoopItem, ITaskPoolNode<AssetBundleRequestAllAssetsWithCancellationSource>
+        {
+            static TaskPool<AssetBundleRequestAllAssetsWithCancellationSource> pool;
+            public AssetBundleRequestAllAssetsWithCancellationSource NextNode { get; set; }
+
+            static AssetBundleRequestAllAssetsWithCancellationSource()
+            {
+                TaskPool.RegisterSizeGetter(typeof(AssetBundleRequestAllAssetsWithCancellationSource), () => pool.Size);
+            }
+
+            readonly Action<AsyncOperation> continuationAction;
+            AssetBundleRequest asyncOperation;
+            CancellationToken cancellationToken;
+            bool completed;
+
+            UniTaskCompletionSourceCore<UnityEngine.Object[]> core;
+
+            AssetBundleRequestAllAssetsWithCancellationSource()
+            {
+                continuationAction = Continuation;
+            }
+
+            public static IUniTaskSource<UnityEngine.Object[]> Create(AssetBundleRequest asyncOperation, CancellationToken cancellationToken, out short token)
+            {
+                if (cancellationToken.IsCancellationRequested)
+                {
+                    return AutoResetUniTaskCompletionSource<UnityEngine.Object[]>.CreateFromCanceled(cancellationToken, out token);
+                }
+
+                if (!pool.TryPop(out var result))
+                {
+                    result = new AssetBundleRequestAllAssetsWithCancellationSource();
+                }
+
+                result.asyncOperation = asyncOperation;
+                result.cancellationToken = cancellationToken;
+                result.completed = false;
+
+                TaskTracker.TrackActiveTask(result, 3);
+
+                PlayerLoopHelper.AddAction(PlayerLoopTiming.Update, result);
+
+                asyncOperation.completed += result.continuationAction;
+
+                token = result.core.Version;
+                return result;
+            }
+
+            void Continuation(AsyncOperation _)
+            {
+                asyncOperation.completed -= continuationAction;
+
+                if (completed)
+                {
+                    TryReturn();
+                }
+                else
+                {
+                    completed = true;
+                    if (cancellationToken.IsCancellationRequested)
+                    {
+                        core.TrySetCanceled(cancellationToken);
+                        return;
+                    }
+
+                    core.TrySetResult(asyncOperation.allAssets);
+                }
+            }
+
+            public UnityEngine.Object[] GetResult(short token)
+            {
+                return core.GetResult(token);
+            }
+
+            void IUniTaskSource.GetResult(short token)
+            {
+                GetResult(token);
+            }
+
+            public UniTaskStatus GetStatus(short token)
+            {
+                return core.GetStatus(token);
+            }
+
+            public UniTaskStatus UnsafeGetStatus()
+            {
+                return core.UnsafeGetStatus();
+            }
+
+            public void OnCompleted(Action<object> continuation, object state, short token)
+            {
+                core.OnCompleted(continuation, state, token);
+            }
+
+            public bool MoveNext()
+            {
+                if (completed)
+                {
+                    TryReturn();
+                    return false;
+                }
+
+                if (cancellationToken.IsCancellationRequested)
+                {
+                    completed = true;
+                    core.TrySetCanceled(cancellationToken);
+                    return false;
+                }
+
+                return true;
+            }
+
+            bool TryReturn()
+            {
+                TaskTracker.RemoveTracking(this);
+                core.Reset();
+                asyncOperation = default;
+                cancellationToken = default;
+                return pool.TryPush(this);
+            }
+        }
+
+        sealed class AssetBundleRequestAllAssetsConfiguredSource : IUniTaskSource<UnityEngine.Object[]>, IPlayerLoopItem, ITaskPoolNode<AssetBundleRequestAllAssetsConfiguredSource>
+        {
+            static TaskPool<AssetBundleRequestAllAssetsConfiguredSource> pool;
+            public AssetBundleRequestAllAssetsConfiguredSource NextNode { get; set; }
+
+            static AssetBundleRequestAllAssetsConfiguredSource()
+            {
+                TaskPool.RegisterSizeGetter(typeof(AssetBundleRequestAllAssetsConfiguredSource), () => pool.Size);
+            }
+
+            AssetBundleRequest asyncOperation;
+            IProgress<float> progress;
+            CancellationToken cancellationToken;
+
+            UniTaskCompletionSourceCore<UnityEngine.Object[]> core;
+
+            AssetBundleRequestAllAssetsConfiguredSource()
+            {
+
+            }
+
+            public static IUniTaskSource<UnityEngine.Object[]> Create(AssetBundleRequest asyncOperation, PlayerLoopTiming timing, IProgress<float> progress, CancellationToken cancellationToken, out short token)
+            {
+                if (cancellationToken.IsCancellationRequested)
+                {
+                    return AutoResetUniTaskCompletionSource<UnityEngine.Object[]>.CreateFromCanceled(cancellationToken, out token);
+                }
+
+                if (!pool.TryPop(out var result))
+                {
+                    result = new AssetBundleRequestAllAssetsConfiguredSource();
+                }
+
+                result.asyncOperation = asyncOperation;
+                result.progress = progress;
+                result.cancellationToken = cancellationToken;
+
+                TaskTracker.TrackActiveTask(result, 3);
+
+                PlayerLoopHelper.AddAction(timing, result);
+
+                token = result.core.Version;
+                return result;
+            }
+
+            public UnityEngine.Object[] GetResult(short token)
+            {
+                try
+                {
+                    return core.GetResult(token);
+                }
+                finally
+                {
+                    TryReturn();
+                }
+            }
+
+            void IUniTaskSource.GetResult(short token)
+            {
+                GetResult(token);
+            }
+
+            public UniTaskStatus GetStatus(short token)
+            {
+                return core.GetStatus(token);
+            }
+
+            public UniTaskStatus UnsafeGetStatus()
+            {
+                return core.UnsafeGetStatus();
+            }
+
+            public void OnCompleted(Action<object> continuation, object state, short token)
+            {
+                core.OnCompleted(continuation, state, token);
+            }
+
+            public bool MoveNext()
+            {
+                if (cancellationToken.IsCancellationRequested)
+                {
+                    core.TrySetCanceled(cancellationToken);
+                    return false;
+                }
+
+                if (progress != null)
+                {
+                    progress.Report(asyncOperation.progress);
+                }
+
+                if (asyncOperation.isDone)
+                {
+                    core.TrySetResult(asyncOperation.allAssets);
+                    return false;
+                }
+
+                return true;
+            }
+
+            bool TryReturn()
+            {
+                TaskTracker.RemoveTracking(this);
+                core.Reset();
+                asyncOperation = default;
+                progress = default;
+                cancellationToken = default;
+                return pool.TryPush(this);
+            }
+        }
+    }
+}
+
+#endif

src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.AssetBundleRequestAllAssets.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: e9147caba40da434da95b39709c13784
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

src/UniTask/Assets/Plugins/UniTask/package.json

@@ -1,7 +1,7 @@
 {
     "name": "com.cysharp.unitask",
     "displayName": "UniTask",
-    "version": "2.0.26",
+    "version": "2.0.27",
     "unity": "2018.4",
     "description": "Provides an efficient async/await integration to Unity.",
     "keywords": [ "async/await", "async", "Task", "UniTask" ],

src/UniTask/Assets/Scenes/SandboxMain.cs

@@ -133,6 +133,7 @@ public class SandboxMain : MonoBehaviour
     UniTaskCompletionSource ucs;
     async UniTask<int> FooAsync()
     {
+
         // use F10, will crash.
         var loop = int.Parse("9");
         await UniTask.DelayFrame(loop);
@@ -190,6 +191,9 @@ public class SandboxMain : MonoBehaviour
 
     async UniTask RunStandardDelayAsync()
     {
+
+
+
         UnityEngine.Debug.Log("DEB");
 
         await UniTask.DelayFrame(30);
@@ -220,6 +224,11 @@ public class SandboxMain : MonoBehaviour
     async UniTaskVoid Update2()
     {
 
+
+
+
+
+
         UnityEngine.Debug.Log("async linq!");
 
         await UniTaskAsyncEnumerable.Range(1, 10)
@@ -455,7 +464,7 @@ public class SandboxMain : MonoBehaviour
 
     private void Awake()
     {
-        PlayerLoopInfo.Inject();
+        // PlayerLoopInfo.Inject();
         PrepareCamera();
     }
 
@@ -473,12 +482,24 @@ public class SandboxMain : MonoBehaviour
         });
     }
 
+    async void RunStandardTaskAsync()
+    {
+        Debug.Log("Wait 3 seconds");
+        await Task.Delay(TimeSpan.FromSeconds(3));
+
+        Debug.Log("Current SyncContext:" + SynchronizationContext.Current.GetType().FullName);
+    }
+
 
     async UniTaskVoid Start()
     {
-        var url =  "http://google.com/404";
-        var webRequestAsyncOperation = UnityWebRequest.Get(url).SendWebRequest();
-        await webRequestAsyncOperation.ToUniTask();
+        RunStandardTaskAsync();
+
+        UnityEngine.Debug.Log("UniTaskPlayerLoop ready? " + PlayerLoopHelper.IsInjectedUniTaskPlayerLoop());
+
+        //var url =  "http://google.com/404";
+        //var webRequestAsyncOperation = UnityWebRequest.Get(url).SendWebRequest();
+        //await webRequestAsyncOperation.ToUniTask();
 
         //PlayerLoopInfo.Inject();
 
@@ -685,7 +706,9 @@ public class SandboxMain : MonoBehaviour
 
         //StartCoroutine(Coroutine());
 
-        //await UniTask.Delay(TimeSpan.FromSeconds(1));
+        // PlayerLoopInfo.Inject();
+        await UniTask.Delay(TimeSpan.FromSeconds(1));
+        PlayerLoopInfo.DumpPlayerLoop("current", PlayerLoop.GetCurrentPlayerLoop());
 
 
         // _ = ReturnToMainThreadTest();
@@ -1051,6 +1074,17 @@ public class SandboxMain : MonoBehaviour
     }
 }
 
+
+public class SyncContextInjecter
+{
+    [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
+    public static void Inject()
+    {
+        SynchronizationContext.SetSynchronizationContext(new UniTaskSynchronizationContext());
+    }
+}
+
+
 public class PlayerLoopInfo
 {
     // [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
@@ -1085,7 +1119,7 @@ public class PlayerLoopInfo
 
     public static Type CurrentLoopType { get; private set; }
 
-    [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
+    // [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
     public static void Inject()
     {
         var system = PlayerLoop.GetCurrentPlayerLoop();

src/UniTask/ProjectSettings/ProjectVersion.txt

@@ -1,2 +1,2 @@
-m_EditorVersion: 2019.3.9f1
-m_EditorVersionWithRevision: 2019.3.9f1 (e6e740a1c473)
+m_EditorVersion: 2019.4.5f1
+m_EditorVersionWithRevision: 2019.4.5f1 (81610f64359c)