From ed47efe4a17a6fa3f0a2a8a36600efdcd1c65b86 Mon Sep 17 00:00:00 2001
From: Yann Pringault <yann.pringault@gmail.com>
Date: Wed, 25 May 2016 11:50:53 -0700
Subject: [PATCH] Add Array.prototype.includes polyfill

Summary:
Add `Array.prototype.includes` polyfill.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes

I had all my `includes` running well on iOS 9 but when switching to Android `includes` threw an error.
[The compatibility table](http://kangax.github.io/compat-table/esnext/#test-Array.prototype.includes_Array.prototype.includes) shows that is not supported on Android yet as well as iOS 6-8.
With Chrome debugging it's working on both environment.
Closes https://github.com/facebook/react-native/pull/7756

Reviewed By: davidaurelio

Differential Revision: D3346873

Pulled By: vjeux

fbshipit-source-id: 2e17d29992873fbe4448b962df0423e516455b4b
---
 docs/JavaScriptEnvironment.md                 |  2 +-
 .../Resolver/polyfills/Array.prototype.es6.js | 36 +++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/docs/JavaScriptEnvironment.md b/docs/JavaScriptEnvironment.md
index 988604fc2c1..4e2e3c1f21d 100644
--- a/docs/JavaScriptEnvironment.md
+++ b/docs/JavaScriptEnvironment.md
@@ -73,7 +73,7 @@ ES6
 * [Object.assign](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/assign)
 * String.prototype.{[startsWith](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/startsWith), [endsWith](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/endsWith), [repeat](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/repeats), [includes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/includes)}
 * [Array.from](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/from)
-* Array.prototype.{[find](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find), [findIndex](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/findIndex)}
+* Array.prototype.{[find](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find), [findIndex](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/findIndex), [includes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes)}
 
 ES7
 
diff --git a/packager/react-packager/src/Resolver/polyfills/Array.prototype.es6.js b/packager/react-packager/src/Resolver/polyfills/Array.prototype.es6.js
index 2752aab5e5d..7e2078f8e92 100644
--- a/packager/react-packager/src/Resolver/polyfills/Array.prototype.es6.js
+++ b/packager/react-packager/src/Resolver/polyfills/Array.prototype.es6.js
@@ -53,3 +53,39 @@ if (!Array.prototype.find) {
     }
   });
 }
+
+// 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;
+    }
+  });
+}