An Object.assign shim. Invoke its “shim” method to shim Object.assign if it is unavailable.
This package implements the es-shim API interface. It works in an ES3-supported environment and complies with the spec. 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:
var assign = require('object.assign').getPolyfill(); // returns native method if compliant /* or */ var assign = require('object.assign/polyfill')(); // returns native method if compliant
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!
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 });
/* 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));
/* 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));
Simply clone the repo, npm install
, and run npm test