src/third_party/v8/test/mjsunit/compiler/deopt-array-iterator-prototype-next.js

// 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 --opt

/* Test deopt behaviors when the prototype has elements */

(function () {
  var array = [,];

  function next() {
    return array[Symbol.iterator]().next();
  }

  %PrepareFunctionForOptimization(next);
  assertEquals(next().value, undefined);
  assertEquals(next().value, undefined);

  %OptimizeFunctionOnNextCall(next);
  assertEquals(next().value, undefined);

  array.__proto__.push(5);
  assertEquals(next().value, 5);
})();