v8/test/mjsunit/harmony/weakrefs/finalizationregistry-keeps-holdings-alive.js
Shu-yu Guo f902b9dd8d [weakrefs] Update FinalizationRegistry to take a per-item callback
Bug: v8:8179
Change-Id: I0cd43db6558db616690de2dd012bf7518c49345d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2138563
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67069}
2020-04-08 17:54:24 +00:00

44 lines
1.3 KiB
JavaScript

// Copyright 2018 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --harmony-weak-refs --expose-gc --noincremental-marking
let cleanup_called = false;
let holdings_list = [];
let cleanup = function(holdings) {
assertFalse(cleanup_called);
holdings_list.push(holdings);
cleanup_called = true;
}
let fg = new FinalizationRegistry(cleanup);
let o1 = {};
let holdings = {'a': 'this is the holdings object'};
// Ignition holds references to objects in temporary registers. These will be
// released when the function exits. So only access o inside a function to
// prevent any references to objects in temporary registers when a gc is
// triggered.
(() => {fg.register(o1, holdings);})()
gc();
assertFalse(cleanup_called);
// Drop the last references to o1.
(() => {o1 = null;})()
// Drop the last reference to the holdings. The FinalizationRegistry keeps it
// alive, so the cleanup function will be called as normal.
holdings = null;
gc();
assertFalse(cleanup_called);
let timeout_func = function() {
assertTrue(cleanup_called);
assertEquals(holdings_list.length, 1);
assertEquals(holdings_list[0].a, "this is the holdings object");
}
setTimeout(timeout_func, 0);