[co19] LanguageFeatures/FinalizationRegistry/ffi/Finalizer/Finalizer_A01_t04 fails on all configurations

[dcharkes]

https://dart-current-results.web.app/#/filter=co19/LanguageFeatures/FinalizationRegistry/ffi/Finalizer/Finalizer_A01_t04&showAll

int called = 0;

final Finalizer finalizer = Finalizer((token) {
  Expect.equals(123, token);
  called++;
});

@pragma('vm:never-inline')
attachToFinalizer() async {
  Object? liveObject;
  Object object = Object();
  finalizer.attach(object, 123);
  await triggerGcWithDelay();
  Expect.equals(0, called);
  liveObject = object;
  () async {
    await triggerGcWithDelay();
    Expect.equals(0, called); // `called = 1`
  }();
  print(liveObject);
}

main() async {
  await attachToFinalizer();
  // Previous triggerGc move some objects to old space. Do multiple GCs to
  // force all objects to old space.
  await triggerGcWithDelay(repeat: 3);
  Expect.equals(1, called);
  await triggerGcWithDelay();
  Expect.equals(1, called);
}

I'm pretty sure this test is wrong. For normal Finalizers that don't require the object to be Finalizable, we don't extend the lifetime to the end of the scope. So the object gets GCed early, leading to the expect failure.

cc @sgrekhov

[dart-github-bot]

Summary: A co19 test for FinalizationRegistry fails because it incorrectly assumes object lifetime extension beyond the scope. The test's expectation of finalizer execution timing is flawed.

[a-siva]

Looks like the test has been fixed, closing this issue.

Usually we open a co19 issue when there is a problem with the test.