Future? _onCancel()

in lib/src/stream_group.dart [229:254]

• 22 lines of code
• 6 McCabe index (conditional complexity)

  Future<void>? _onCancel() {
    _state = _StreamGroupState.canceled;

    var futures = _subscriptions.entries
        .map((entry) {
          var subscription = entry.value;
          try {
            if (subscription != null) return subscription.cancel();
            return entry.key.listen(null).cancel();
          } catch (_) {
            return null;
          }
        })
        .whereNotNull()
        .toList();

    _subscriptions.clear();

    var onIdleController = _onIdleController;
    if (onIdleController != null && !onIdleController.isClosed) {
      onIdleController.add(null);
      onIdleController.close();
    }

    return futures.isEmpty ? null : Future.wait(futures);
  }