#object.assign [![Version Badge][npm-version-svg]][npm-url] [![Build Status][travis-svg]][travis-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]][npm-url] [![browser support][testling-png]][testling-url] An Object.assign shim. Invoke its "shim" method to shim Object.assign if it is unavailable. This package implements the [es-shim API](https://github.com/es-shims/api) interface. It works in an ES3-supported environment and complies with the [spec](http://www.ecma-international.org/ecma-262/6.0/#sec-object.assign). In an ES6 environment, it will also work properly with `Symbol`s. Takes a minimum of 2 arguments: `target` and `source`. Takes a variable sized list of source arguments - at least 1, as many as you want. Throws a TypeError if the `target` argument is `null` or `undefined`. Most common usage: ```js var assign = require('object.assign').getPolyfill(); // returns native method if compliant /* or */ var assign = require('object.assign/polyfill')(); // returns native method if compliant ``` ## Example ```js var assert = require('assert'); // Multiple sources! var target = { a: true }; var source1 = { b: true }; var source2 = { c: true }; var sourceN = { n: true }; var expected = { a: true, b: true, c: true, n: true }; assign(target, source1, source2, sourceN); assert.deepEqual(target, expected); // AWESOME! ``` ```js var target = { a: true, b: true, c: true }; var source1 = { c: false, d: false }; var sourceN = { e: false }; var assigned = assign(target, source1, sourceN); assert.equal(target, assigned); // returns the target object assert.deepEqual(assigned, { a: true, b: true, c: false, d: false, e: false }); ``` ```js /* when Object.assign is not present */ delete Object.assign; var shimmedAssign = require('object.assign').shim(); /* or */ var shimmedAssign = require('object.assign/shim')(); assert.equal(shimmedAssign, assign); var target = { a: true, b: true, c: true }; var source = { c: false, d: false, e: false }; var assigned = assign(target, source); assert.deepEqual(Object.assign(target, source), assign(target, source)); ``` ```js /* when Object.assign is present */ var shimmedAssign = require('object.assign').shim(); assert.equal(shimmedAssign, Object.assign); var target = { a: true, b: true, c: true }; var source = { c: false, d: false, e: false }; assert.deepEqual(Object.assign(target, source), assign(target, source)); ``` ## Tests Simply clone the repo, `npm install`, and run `npm test` [npm-url]: https://npmjs.org/package/object.assign [npm-version-svg]: http://versionbadg.es/ljharb/object.assign.svg [travis-svg]: https://travis-ci.org/ljharb/object.assign.svg [travis-url]: https://travis-ci.org/ljharb/object.assign [deps-svg]: https://david-dm.org/ljharb/object.assign.svg?theme=shields.io [deps-url]: https://david-dm.org/ljharb/object.assign [dev-deps-svg]: https://david-dm.org/ljharb/object.assign/dev-status.svg?theme=shields.io [dev-deps-url]: https://david-dm.org/ljharb/object.assign#info=devDependencies [testling-png]: https://ci.testling.com/ljharb/object.assign.png [testling-url]: https://ci.testling.com/ljharb/object.assign [npm-badge-png]: https://nodei.co/npm/object.assign.png?downloads=true&stars=true [license-image]: http://img.shields.io/npm/l/object.assign.svg [license-url]: LICENSE [downloads-image]: http://img.shields.io/npm/dm/object.assign.svg [downloads-url]: http://npm-stat.com/charts.html?package=object.assign