LanguageFeatures/FinalizationRegistry/ffi/Finalizer/attach_A06_t02.dart

// Copyright (c) 2022, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

/// @assertion The finalizer can be attached multiple times to the same object
/// with different, or the same, finalization token.
///
/// @description Checks that finalizer can be attached to the same object with
/// the different finalization tokens.
/// @author iarkh@unipro.ru

import '../../gc_utils_lib.dart';
import '../../../../Utils/expect.dart';

class Nonce {
  final int value;
  Nonce(this.value);
}

final finalizerTokens = <String>{};
int count = 0;

final Finalizer finalizer = Finalizer((token) {
  if (count >= 0) {
    if (finalizerTokens.contains(token)) {
      count = -1;
    } else {
      finalizerTokens.add(token);
      count++;
    }
  }
});

@pragma('vm:never-inline')
void attachToFinalizer(Nonce token) {
  Object value = Object();
  finalizer.attach(value, "Finalization token 1", detach: token);
  finalizer.attach(value, "Finalization token 2", detach: token);
  finalizer.attach(value, "Finalization token 3", detach: token);
}

main() async {
  Nonce token = Nonce(1);
  attachToFinalizer(token);

  await triggerGcWithDelay();
  Expect.setEquals(
      {"Finalization token 1", "Finalization token 2", "Finalization token 3"},
      finalizerTokens);
  Expect.equals(3, count);
}