test262/implementation-contributed/v8/mjsunit/es6/string-iterator2.js

27 lines
843 B
JavaScript

// Copyright 2018 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --allow-natives-syntax --no-stress-opt
// Tests for spreading primitive strings.
assertEquals([...''], []);
var str = 'ott';
assertEquals(['o', 't', 't'], [...str]);
assertTrue(%StringIteratorProtector());
str[Symbol.iterator] = {};
// Symbol.iterator can't be set on primitive strings, so it shouldn't invalidate
// the protector.
assertTrue(%StringIteratorProtector());
// This changes the String Iterator prototype. No more tests should be run after
// this in the same instance.
var iterator = str[Symbol.iterator]();
iterator.__proto__.next = () => ({value : undefined, done : true});
assertFalse(%StringIteratorProtector());
assertEquals([], [...str]);