Suspend test synchronization context

Author: sakno

src/DotNext.Tests/Runtime/CompilerServices/SpawningAsyncTaskMethodBuilderTests.cs

@@ -9,7 +9,7 @@ public sealed class SpawningAsyncTaskMethodBuilderTests : Test
     public static async Task ForkAsyncMethodWithResult()
     {
         var resetEvent = new TaskCompletionSource();
-        var task = SuspendContext(() => Sum(40, 2, Thread.CurrentThread.ManagedThreadId));
+        var task = Sum(40, 2, Thread.CurrentThread.ManagedThreadId);
         await resetEvent.Task.WaitAsync(DefaultTimeout);
 
         Equal(42, await task);
@@ -29,7 +29,7 @@ async Task<int> Sum(int x, int y, int callerThreadId)
     public static async Task ForkAsyncMethodWithoutResult()
     {
         var resetEvent = new TaskCompletionSource();
-        var task = SuspendContext(() => CheckThreadId(Thread.CurrentThread.ManagedThreadId));
+        var task = CheckThreadId(Thread.CurrentThread.ManagedThreadId);
         await resetEvent.Task.WaitAsync(DefaultTimeout);
 
         await task;
@@ -48,7 +48,7 @@ async Task CheckThreadId(int callerThreadId)
     public static async Task CancellationOfSpawnedMethod()
     {
         var resetEvent = new TaskCompletionSource();
-        var task = SuspendContext(() => CheckThreadId(Thread.CurrentThread.ManagedThreadId, new(true)));
+        var task = CheckThreadId(Thread.CurrentThread.ManagedThreadId, new(true));
         await resetEvent.Task.WaitAsync(DefaultTimeout);
 
         await task.ConfigureAwait(ConfigureAwaitOptions.ContinueOnCapturedContext | ConfigureAwaitOptions.SuppressThrowing);

src/DotNext.Tests/Test.cs

@@ -45,18 +45,4 @@ private protected static ReadOnlySequence<T> ToReadOnlySequence<T>(ReadOnlyMemor
     private protected static Action<T> Same<T>(T expected)
         where T : class
         => actual => Same(expected, actual);
-
-    protected static TResult SuspendContext<TResult>(Func<TResult> func)
-    {
-        var currentContext = SynchronizationContext.Current;
-        SynchronizationContext.SetSynchronizationContext(null);
-        try
-        {
-            return func();
-        }
-        finally
-        {
-            SynchronizationContext.SetSynchronizationContext(currentContext);
-        }
-    }
 }

src/DotNext.Tests/Threading/Leases/LeaseTests.cs

@@ -132,7 +132,7 @@ public static async Task WorkerProtectedWithLease()
         await using var consumer = new TestLeaseConsumer(provider);
         True(await consumer.TryAcquireAsync());
 
-        var result = await SuspendContext(() => consumer.ExecuteAsync(Worker));
+        var result = await consumer.ExecuteAsync(Worker);
         Equal(42, result);
 
         static async Task<int> Worker(CancellationToken token)

src/DotNext/Runtime/CompilerServices/SpawningTaskMethodBuilder.cs

@@ -31,8 +31,17 @@ public struct SpawningAsyncTaskMethodBuilder<TResult>()
     public void Start<TStateMachine>(ref TStateMachine stateMachine)
         where TStateMachine : IAsyncStateMachine
     {
+#if DEBUG
+        var currentContext = SynchronizationContext.Current;
+        SynchronizationContext.SetSynchronizationContext(null);
+#endif
+
         var awaiter = System.Threading.Tasks.Task.Yield().GetAwaiter();
         builder.AwaitUnsafeOnCompleted(ref awaiter, ref stateMachine);
+
+#if DEBUG
+        SynchronizationContext.SetSynchronizationContext(currentContext);
+#endif
     }
 
     /// <summary>
@@ -114,8 +123,17 @@ public struct SpawningAsyncTaskMethodBuilder()
     public void Start<TStateMachine>(ref TStateMachine stateMachine)
         where TStateMachine : IAsyncStateMachine
     {
+#if DEBUG
+        var currentContext = SynchronizationContext.Current;
+        SynchronizationContext.SetSynchronizationContext(null);
+#endif
+
         var awaiter = Task.Yield().GetAwaiter();
         builder.AwaitUnsafeOnCompleted(ref awaiter, ref stateMachine);
+
+#if DEBUG
+        SynchronizationContext.SetSynchronizationContext(currentContext);
+#endif
     }
 
     /// <summary>