1 // Copyright 2015 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // Flags: --harmony-species 6 7 // Test the ES2015 @@species feature 8 9 'use strict'; 10 11 let TypedArray = Uint8Array.__proto__; 12 13 // The @@species property exists on the right objects and has the right values 14 15 let classesWithSpecies = [RegExp, Array, TypedArray, ArrayBuffer, Map, Set, Promise]; 16 let classesWithoutSpecies = [Object, Function, String, Number, Symbol, WeakMap, WeakSet]; 17 18 for (let constructor of classesWithSpecies) { 19 assertEquals(constructor, constructor[Symbol.species]); 20 assertThrows(function() { constructor[Symbol.species] = undefined }, TypeError); 21 let descriptor = Object.getOwnPropertyDescriptor(constructor, Symbol.species); 22 assertTrue(descriptor.configurable); 23 assertFalse(descriptor.enumerable); 24 assertEquals(undefined, descriptor.writable); 25 assertEquals(undefined, descriptor.set); 26 assertEquals('function', typeof descriptor.get); 27 } 28 29 // @@species is defined with distinct getters 30 assertEquals(classesWithSpecies.length, 31 new Set(classesWithSpecies.map(constructor => 32 Object.getOwnPropertyDescriptor( 33 constructor, Symbol.species).get) 34 ).size); 35 36 for (let constructor of classesWithoutSpecies) 37 assertEquals(undefined, constructor[Symbol.species]); 38
