Leaked stream in async

main.dart

import 'dart:async';

Future<void> foo() async {
  await for (final i in Stream<int>.periodic(const Duration(milliseconds: 500), (x) => x)) {
    print('$i');
  }
}

void main() async {
  // once this is awaited, the inner implicit stream subscription is uncancalleble
  await foo();
}