init method

Implementation

@override
Future<bool> init() async {
  final receivePort = ReceivePort();
  _receivePort = receivePort;
  _exitCompleter = Completer<void>();
  final completer = Completer<SendPort>();

  receivePort.listen((message) {
    if (message is _ReadyMessage) {
      completer.complete(message.sendPort);

      return;
    }
    if (message is _HandleIdNotification) {
      _handleId = message.handleId;

      return;
    }
    if (message is _Response) {
      final pending = _pending.remove(message.id);
      pending?.complete(message);

      return;
    }
    // Isolate exit (null from addOnExitListener).
    if (message == null) {
      if (_exitCompleter != null && !_exitCompleter!.isCompleted) {
        _exitCompleter!.complete();
      }
      if (!completer.isCompleted) {
        completer.completeError(
          StateError('Isolate exited before sending _ReadyMessage'),
        );
      }
      _failAllPending('Isolate exited');

      return;
    }
    // Isolate error (List from addErrorListener) — fail pending futures.
    if (!completer.isCompleted) {
      completer.completeError(
        StateError('Isolate failed to start: $message'),
      );
    }
    _failAllPending('Isolate error: $message');
  });

  final isolate = await Isolate.spawn(
    _isolateEntryPoint,
    _InitMessage(receivePort.sendPort),
  );
  _isolate = isolate;

  isolate
    ..addOnExitListener(receivePort.sendPort)
    ..addErrorListener(receivePort.sendPort);

  _sendPort = await completer.future.timeout(
    initTimeout ?? const Duration(seconds: 30),
    onTimeout: () => throw StateError(
      'Worker isolate failed to initialize within timeout. '
      'Possible silent crash before _ReadyMessage was sent.',
    ),
  );

  // Initialize FFI on the main isolate so that MontyCancelToken and
  // direct NativeBindingsFfi access work cross-isolate.  Dart static
  // state is per-isolate, so the worker's NativeBindingsFfi registration
  // does not propagate here.
  NativeBindingsFfi.ensureInitialized();

  return true;
}