Fix Monitor.Wait runtime error in WASM by replacing blocking wait patterns

[Copilot]

WASM single-threaded runtime throws "Cannot wait on monitors on this runtime" when user code uses .GetAwaiter().GetResult() or .Wait() on Tasks, as these internally call Monitor.Wait.

Changes

• WasmTask.RunSync helpers: Check IsCompleted before accessing task results, avoiding blocking waits
• Code preprocessing: Transform blocking patterns to use WasmTask.RunSync:
  • task.GetAwaiter().GetResult() → WasmHelpers.WasmTask.RunSync(task)
  • task.Wait() → WasmHelpers.WasmTask.RunSync(task)
• Regex improvements: Handle one level of nested parentheses for method calls like Method(Inner())
• Runner update: Check task completion status instead of blocking

Example

// Before: Fails with Monitor.Wait error
static void Main()
{
    RunAsync().GetAwaiter().GetResult();
}

// After preprocessing: Works in WASM
static void Main()
{
    WasmHelpers.WasmTask.RunSync(RunAsync());
}

Combined with the existing Task.Delay → WasmTask.Delay transformation, async methods complete synchronously, making the IsCompleted check succeed without blocking.

Original prompt

続き
直っていない

実行エラー: Cannot wait on monitors on this runtime.

スタックトレース:
at System.Threading.Monitor.ObjWait(Int32 millisecondsTimeout, Object obj)
at System.Threading.Monitor.Wait(Object obj, Int32 millisecondsTimeout)
at System.Threading.ManualResetEventSlim.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
at System.Threading.Tasks.Task.SpinThenBlockingWait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
at System.Threading.Tasks.Task.InternalWaitCore(Int32 millisecondsTimeout, CancellationToken cancellationToken)
at System.Threading.Tasks.Task.InternalWait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
at Program.Main()
at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

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[yamayu-dev]

@copilot テストして結果を報告して下さい

[Copilot]

@copilot テストして結果を報告して下さい

テスト結果を報告します:

✅ 全てのテストが成功しました

1. コード前処理テスト - 4パターン全てPASS

   • RunAsync().GetAwaiter().GetResult() → WasmHelpers.WasmTask.RunSync(RunAsync())
   • task.Wait() → WasmHelpers.WasmTask.RunSync(task)
   • SomeAsync().Wait() → WasmHelpers.WasmTask.RunSync(SomeAsync())
   • Outer(Inner()).GetAwaiter().GetResult() → ネストした括弧も正しく変換

2. 実行テスト - 問題のコードが正常に動作

   • 元のエラーコード(RunAsync().GetAwaiter().GetResult() + Task.Delay)が "Hello from async!" を出力
   • .Wait() パターンも正常動作