array-includes

#array-includes

A spec-compliant Array.prototype.includes shim/polyfill/replacement that works as far down as ES3.

This package implements the es-shim API interface. It works in an ES3-supported environment and complies with the proposed spec.

Because Array.prototype.includes depends on a receiver (the “this” value), the main export takes the array to operate on as the first argument.

Example

var includes = require('array-includes');
var assert = require('assert');
var arr = {
	1,
	'foo',
	NaN,
	-0
};
assert.equal(arr.indexOf(0) > -1, true);
assert.equal(arr.indexOf(-0) > -1, true);
assert.equal(includes(arr, 0), false);
assert.equal(includes(arr, -0), true);

assert.equal(arr.indexOf(NaN) > -1, false);
assert.equal(includes(arr, NaN), true);

assert.equal(includes(arr, 'foo', 0), true);
assert.equal(includes(arr, 'foo', 1), true);
assert.equal(includes(arr, 'foo', 2), false);

var includes = require('array-includes');
var assert = require('assert');
/* when Array#includes is not present */
delete Array.prototype.includes;
var shimmedIncludes = includes.shim();
assert.equal(shimmedIncludes, includes);
assert.deepEqual(arr.includes('foo', 1), includes(arr, 'foo', 1));

var includes = require('array-includes');
var assert = require('assert');
/* when Array#includes is present */
var shimmedIncludes = includes.shim();
assert.notEqual(shimmedIncludes, includes);
assert.equal(shimmedIncludes, Array.prototype.includes);
assert.deepEqual(arr.includes(1, 'foo'), includes(arr, 1, 'foo'));

Tests

Simply clone the repo, npm install, and run npm test

Similar packages

Other packages similar to array-includes

lodash.includes

Lodash is a popular utility library that includes a method called _.includes. This method is similar to array-includes but offers additional features such as deep path string checks for objects and is part of a larger utility library.

underscore

Underscore is another utility library that provides a method called _.contains (also aliased as _.includes). It is similar to array-includes but is part of a larger set of utility functions for working with arrays, objects, and functions.