react-native/Libraries/polyfills/Array.prototype.es6.js
Miguel Jimenez Esun ad0fe15e2e Move polyfills to react-native
Summary:
React Native bundler (aka Metro Bundler) was splitted from the main codebase some time ago (now it lives [[https://github.com/facebook/metro-bundler|here]]). To make it more agnostic, polyfills will be moved out from it, so people who doesn't need them does not include them. However, RN will still need them, so the first step is to copy them back to RN so that we can provide them to Metro Bundler later.

We also include a way of passing the list of polyfills to include, as an `Array<string>`. The field is called `polyfills`, and defaults to the traditional list that is currently included in the package manager [see here](be1843cddc/packages/metro-bundler/src/defaults.js (L27-L37)).

In future commits, `metro-bundler` will be able to manage the `polyfills` array passed to it, and use it, instead of the pre-defined ones.

Reviewed By: davidaurelio

Differential Revision: D5381614

fbshipit-source-id: 749d536b781843ecb3067803e44398cd6df941f1
2017-07-11 03:47:16 -07:00

96 lines
2.5 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @polyfill
*/
/* eslint-disable */
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/findIndex
function findIndex(predicate, context) {
if (this == null) {
throw new TypeError(
'Array.prototype.findIndex called on null or undefined'
);
}
if (typeof predicate !== 'function') {
throw new TypeError('predicate must be a function');
}
var list = Object(this);
var length = list.length >>> 0;
for (var i = 0; i < length; i++) {
if (predicate.call(context, list[i], i, list)) {
return i;
}
}
return -1;
}
if (!Array.prototype.findIndex) {
Object.defineProperty(Array.prototype, 'findIndex', {
enumerable: false,
writable: true,
configurable: true,
value: findIndex
});
}
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find
if (!Array.prototype.find) {
Object.defineProperty(Array.prototype, 'find', {
enumerable: false,
writable: true,
configurable: true,
value: function(predicate, context) {
if (this == null) {
throw new TypeError(
'Array.prototype.find called on null or undefined'
);
}
var index = findIndex.call(this, predicate, context);
return index === -1 ? undefined : this[index];
}
});
}
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes
if (!Array.prototype.includes) {
Object.defineProperty(Array.prototype, 'includes', {
enumerable: false,
writable: true,
configurable: true,
value: function (searchElement) {
var O = Object(this);
var len = parseInt(O.length) || 0;
if (len === 0) {
return false;
}
var n = parseInt(arguments[1]) || 0;
var k;
if (n >= 0) {
k = n;
} else {
k = len + n;
if (k < 0) {
k = 0;
}
}
var currentElement;
while (k < len) {
currentElement = O[k];
if (searchElement === currentElement ||
(searchElement !== searchElement && currentElement !== currentElement)) {
return true;
}
k++;
}
return false;
}
});
}