From 3e00735b3d20e3a70b39e24844aa205e8ed0e590 Mon Sep 17 00:00:00 2001
From: neuecc <ils@neue.cc>
Date: Mon, 15 Jun 2020 15:23:25 +0900
Subject: [PATCH] Add AsUniTaskAsyncEnumerable/AsAsyncEnumerable in .NET Core

---
 .../NetCore/AsyncEnumerableExtensions.cs      | 101 ++++++++++++++++++
 .../NetCore/UniTask.AsValueTask.cs            |   9 +-
 2 files changed, 105 insertions(+), 5 deletions(-)
 create mode 100644 src/UniTask.NetCore/NetCore/AsyncEnumerableExtensions.cs

diff --git a/src/UniTask.NetCore/NetCore/AsyncEnumerableExtensions.cs b/src/UniTask.NetCore/NetCore/AsyncEnumerableExtensions.cs
new file mode 100644
index 0000000..33e9674
--- /dev/null
+++ b/src/UniTask.NetCore/NetCore/AsyncEnumerableExtensions.cs
@@ -0,0 +1,101 @@
+#if !NETSTANDARD2_0
+
+#pragma warning disable 0649
+
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using System.Threading.Tasks.Sources;
+
+namespace Cysharp.Threading.Tasks
+{
+    public static class AsyncEnumerableExtensions
+    {
+        public static IUniTaskAsyncEnumerable<T> AsUniTaskAsyncEnumerable<T>(this IAsyncEnumerable<T> source)
+        {
+            return new AsyncEnumerableToUniTaskAsyncEnumerable<T>(source);
+        }
+
+        public static IAsyncEnumerable<T> AsAsyncEnumerable<T>(this IUniTaskAsyncEnumerable<T> source)
+        {
+            return new UniTaskAsyncEnumerableToAsyncEnumerable<T>(source);
+        }
+
+        sealed class AsyncEnumerableToUniTaskAsyncEnumerable<T> : IUniTaskAsyncEnumerable<T>
+        {
+            readonly IAsyncEnumerable<T> source;
+
+            public AsyncEnumerableToUniTaskAsyncEnumerable(IAsyncEnumerable<T> source)
+            {
+                this.source = source;
+            }
+
+            public IUniTaskAsyncEnumerator<T> GetAsyncEnumerator(CancellationToken cancellationToken = default)
+            {
+                return new Enumerator(source.GetAsyncEnumerator(cancellationToken));
+            }
+
+            sealed class Enumerator : IUniTaskAsyncEnumerator<T>
+            {
+                readonly IAsyncEnumerator<T> enumerator;
+
+                public Enumerator(IAsyncEnumerator<T> enumerator)
+                {
+                    this.enumerator = enumerator;
+                }
+
+                public T Current => enumerator.Current;
+
+                public async UniTask DisposeAsync()
+                {
+                    await enumerator.DisposeAsync();
+                }
+
+                public async UniTask<bool> MoveNextAsync()
+                {
+                    return await enumerator.MoveNextAsync();
+                }
+            }
+        }
+
+        sealed class UniTaskAsyncEnumerableToAsyncEnumerable<T> : IAsyncEnumerable<T>
+        {
+            readonly IUniTaskAsyncEnumerable<T> source;
+
+            public UniTaskAsyncEnumerableToAsyncEnumerable(IUniTaskAsyncEnumerable<T> source)
+            {
+                this.source = source;
+            }
+
+            public IAsyncEnumerator<T> GetAsyncEnumerator(CancellationToken cancellationToken = default)
+            {
+                return new Enumerator(source.GetAsyncEnumerator(cancellationToken));
+            }
+
+            sealed class Enumerator : IAsyncEnumerator<T>
+            {
+                readonly IUniTaskAsyncEnumerator<T> enumerator;
+
+                public Enumerator(IUniTaskAsyncEnumerator<T> enumerator)
+                {
+                    this.enumerator = enumerator;
+                }
+
+                public T Current => enumerator.Current;
+
+                public ValueTask DisposeAsync()
+                {
+                    return enumerator.DisposeAsync();
+                }
+
+                public ValueTask<bool> MoveNextAsync()
+                {
+                    return enumerator.MoveNextAsync();
+                }
+            }
+        }
+    }
+}
+
+#endif
\ No newline at end of file
diff --git a/src/UniTask.NetCore/NetCore/UniTask.AsValueTask.cs b/src/UniTask.NetCore/NetCore/UniTask.AsValueTask.cs
index 103d129..c3c4b7a 100644
--- a/src/UniTask.NetCore/NetCore/UniTask.AsValueTask.cs
+++ b/src/UniTask.NetCore/NetCore/UniTask.AsValueTask.cs
@@ -26,15 +26,14 @@ namespace Cysharp.Threading.Tasks
 #endif
         }
 
-        public static UniTask<T> AsUniTask<T>(this ValueTask<T> task, bool useCurrentSynchronizationContext = true)
+        public static async UniTask<T> AsUniTask<T>(this ValueTask<T> task)
         {
-            // NOTE: get _obj and _token directly for low overhead conversion but not yet implemented.
-            return task.AsTask().AsUniTask(useCurrentSynchronizationContext);
+            return await task;
         }
 
-        public static UniTask AsUniTask(this ValueTask task, bool useCurrentSynchronizationContext = true)
+        public static async UniTask AsUniTask(this ValueTask task)
         {
-            return task.AsTask().AsUniTask(useCurrentSynchronizationContext);
+            await task;
         }
 
 #if NETSTANDARD2_0