avoid-unassigned-stream-subscriptions

added in: 1.13.0

warning

preset: recommended

Warns when a stream subscription is not assigned to a variable.

Not disposing stream subscriptions may lead to a memory leak.

Example

❌ Bad:

void fn() {
  final stream = Stream.fromIterable([1, 2, 3]);

  // LINT
  stream.listen((event) {
    print(event);
  });
}

✅ Good:

void fn() {
  final stream = Stream.fromIterable([1, 2, 3]);

  final savedSubscription = stream.listen((event) {
    print(event);
  });

  ...

  savedSubscription.cancel();
}