mirror-rhinstaller-node-cache/is-finalizationregistry
2026-07-22 07:15:03 +00:00
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test 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
.eslintrc 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
.nycrc 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
CHANGELOG.md 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
index.d.ts 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
index.js 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
LICENSE 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
package.json 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
README.md 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00
tsconfig.json 70a54663980edde26ebea82117fe36be1872d66a4e0b8026c243e93fe6b54685 package.json 2026-07-22 07:15:03 +00:00

is-finalizationregistry Version Badge

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Is this value a JS FinalizationRegistry? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Example

var isFinalizationRegistry = require('is-finalizationregistry');
assert(!isFinalizationRegistry(function () {}));
assert(!isFinalizationRegistry(null));
assert(!isFinalizationRegistry(function* () { yield 42; return Infinity; });
assert(!isFinalizationRegistry(Symbol('foo')));
assert(!isFinalizationRegistry(1n));
assert(!isFinalizationRegistry(Object(1n)));

assert(!isFinalizationRegistry(new Set()));
assert(!isFinalizationRegistry(new WeakSet()));
assert(!isFinalizationRegistry(new Map()));
assert(!isFinalizationRegistry(new WeakMap()));
assert(!isFinalizationRegistry(new WeakRef({})));

assert(isFinalizationRegistry(new FinalizationRegistry(function () {})));

class MyFinalizationRegistry extends FinalizationRegistry {}
assert(isFinalizationRegistry(new MyFinalizationRegistry(function () {})));

Tests

Simply clone the repo, npm install, and run npm test