is-finalizationregistry

is-finalizationregistry

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

Changelog

v1.0.1 - 2020-12-04

Commits

• [Tests] migrate tests to Github Actions b697250
• [Tests] run nyc on all tests 9091806
• [actions] add "Allow Edits" workflow 5d8c4f5
• [Dev Deps] update eslint, @ljharb/eslint-config, aud, auto-changelog, object-inspect 3af34c1
• [actions] switch Automatic Rebase workflow to pull_request_target event d0720ff
• [readme] remove travis badge 2757b27
• [meta] add package.json to exports c680142