Initial Save

node_modules/is-finalizationregistry/README.md

@@ -0,0 +1,54 @@
+# is-finalizationregistry <sup>[![Version Badge][npm-version-svg]][package-url]</sup>
+
+[![github actions][actions-image]][actions-url]
+[![coverage][codecov-image]][codecov-url]
+[![dependency status][deps-svg]][deps-url]
+[![dev dependency status][dev-deps-svg]][dev-deps-url]
+[![License][license-image]][license-url]
+[![Downloads][downloads-image]][downloads-url]
+
+[![npm badge][npm-badge-png]][package-url]
+
+Is this value a JS FinalizationRegistry? This module works cross-realm/iframe, and despite ES6 @@toStringTag.
+
+## Example
+
+```js
+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`
+
+[package-url]: https://npmjs.org/package/is-finalizationregistry
+[npm-version-svg]: https://versionbadg.es/inspect-js/is-finalizationregistry.svg
+[deps-svg]: https://david-dm.org/inspect-js/is-finalizationregistry.svg
+[deps-url]: https://david-dm.org/inspect-js/is-finalizationregistry
+[dev-deps-svg]: https://david-dm.org/inspect-js/is-finalizationregistry/dev-status.svg
+[dev-deps-url]: https://david-dm.org/inspect-js/is-finalizationregistry#info=devDependencies
+[npm-badge-png]: https://nodei.co/npm/is-finalizationregistry.png?downloads=true&stars=true
+[license-image]: https://img.shields.io/npm/l/is-finalizationregistry.svg
+[license-url]: LICENSE
+[downloads-image]: https://img.shields.io/npm/dm/is-finalizationregistry.svg
+[downloads-url]: https://npm-stat.com/charts.html?package=is-finalizationregistry
+[codecov-image]: https://codecov.io/gh/inspect-js/is-finalizationregistry/branch/main/graphs/badge.svg
+[codecov-url]: https://app.codecov.io/gh/inspect-js/is-finalizationregistry/
+[actions-image]: https://img.shields.io/endpoint?url=https://github-actions-badge-u3jn4tfpocch.runkit.sh/inspect-js/is-finalizationregistry
+[actions-url]: https://github.com/inspect-js/is-finalizationregistry/actions