JSTests/test262/test/language/statements/for-of/map.js

// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.

/*---
description: Map traversal using for..of
info: |
    Map instances should be able to be traversed using a `for...of` loop.
es6id: 13.6.4
features: [Map]
---*/

var map = new Map();
var obj = {};
var iterationCount = 0;

var first = [0, 'a'];
var second = [true, false];
var third = [null, undefined];
var fourth = [NaN, obj];

map.set(0, 'a');
map.set(true, false);
map.set(null, undefined);
map.set(NaN, obj);

for (var x of map) {
  assert.sameValue(x[0], first[0]);
  assert.sameValue(x[1], first[1]);
  first = second;
  second = third;
  third = fourth;
  fourth = null;
  iterationCount += 1;
}

assert.sameValue(iterationCount, 4);