| 'use strict'; | 
| var $ = require('../internals/export'); | 
| var IS_PURE = require('../internals/is-pure'); | 
| var FORCED_PROMISE_CONSTRUCTOR = require('../internals/promise-constructor-detection').CONSTRUCTOR; | 
| var NativePromiseConstructor = require('../internals/promise-native-constructor'); | 
| var getBuiltIn = require('../internals/get-built-in'); | 
| var isCallable = require('../internals/is-callable'); | 
| var defineBuiltIn = require('../internals/define-built-in'); | 
|   | 
| var NativePromisePrototype = NativePromiseConstructor && NativePromiseConstructor.prototype; | 
|   | 
| // `Promise.prototype.catch` method | 
| // https://tc39.es/ecma262/#sec-promise.prototype.catch | 
| $({ target: 'Promise', proto: true, forced: FORCED_PROMISE_CONSTRUCTOR, real: true }, { | 
|   'catch': function (onRejected) { | 
|     return this.then(undefined, onRejected); | 
|   } | 
| }); | 
|   | 
| // makes sure that native promise-based APIs `Promise#catch` properly works with patched `Promise#then` | 
| if (!IS_PURE && isCallable(NativePromiseConstructor)) { | 
|   var method = getBuiltIn('Promise').prototype['catch']; | 
|   if (NativePromisePrototype['catch'] !== method) { | 
|     defineBuiltIn(NativePromisePrototype, 'catch', method, { unsafe: true }); | 
|   } | 
| } |