// Copyright 2017 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 (function modifyNext() { 'use strict'; class Point { constructor(x, y) { this.x = x; this.y = y; } } class ArgumentsPoint extends Point { constructor() { super(...arguments); } } var a = []; var ai = a[Symbol.iterator](); var original_next = ai.__proto__['next']; function testArgumentsPoint(x, y) { return new ArgumentsPoint(x, y); } testArgumentsPoint(1, 2); testArgumentsPoint(1, 2); %OptimizeFunctionOnNextCall(testArgumentsPoint); var r = testArgumentsPoint(1, 2); assertInstanceof(r, ArgumentsPoint); assertInstanceof(r, Point); assertEquals(r.x, 1); assertEquals(r.y, 2); var called = 0; Object.defineProperty(ai.__proto__, 'next', { get: function() { called++; return original_next; } }); var r2 = testArgumentsPoint(1, 2); assertEquals(3, called); assertInstanceof(r2, ArgumentsPoint); assertInstanceof(r2, Point); assertEquals(r2.x, 1); assertEquals(r2.y, 2); })();