hasown 
A robust, ES3 compatible, "has own property" predicate.
Example
const assert = require('assert');
const hasOwn = require('hasown');
assert.equal(hasOwn({}, 'toString'), false);
assert.equal(hasOwn([], 'length'), true);
assert.equal(hasOwn({ a: 42 }, 'a'), true);
Tests
Simply clone the repo, npm install
, and run npm test