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// 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);
})();
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