v8/test/mjsunit/json-stringify-holder.js

// Copyright 2016 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.

(function testBasic() {
  var stack = [];
  var object = {a: false};
  var replaced = {a: false, replaced: true};

  function replacer(key, value) {
    stack.push({ holder: this, key, value });
    if (stack.length === 1) return replaced;
    if (key === "a") return true;
    return value;
  }

  assertEquals(`{"a":true,"replaced":true}`, JSON.stringify(object, replacer));

  assertEquals([
    {
      holder: { "": { a: false } },
      key: "",
      value: { a: false }
    },
    {
      holder: { a: false, replaced: true },
      key: "a",
      value: false
    },
    {
      holder: { a: false, replaced: true },
      key: "replaced",
      value: true
    }
  ], stack);

  assertSame(stack[0].holder[""], object);
  assertSame(stack[0].value, object);
  assertSame(stack[1].holder, replaced);
  assertSame(stack[2].holder, replaced);
})();

(function testToJSON() {
  var stack = [];
  var object = {a: false, toJSON };
  var nested = { toJSON: nestedToJSON };
  var replaced = {a: false, replaced: true, nested };
  var toJSONd = {a: false, toJSONd: true }
  var nestedToJSONd = { nestedToJSONd: true };

  function toJSON(key, value) {
    return toJSONd;
  }

  function nestedToJSON(key, value) {
    return nestedToJSONd;
  }

  function replacer(key, value) {
    stack.push({ holder: this, key, value });
    if (stack.length === 1) return replaced;
    if (key === "a") return true;
    return value;
  }

  assertEquals(`{"a":true,"replaced":true,"nested":{"nestedToJSONd":true}}`,
               JSON.stringify(object, replacer));

  assertEquals([
    {
      holder: { "": { a: false, toJSON: toJSON } },
      key: "",
      value: { a: false, toJSONd: true }
    },
    {
      holder: { a: false, replaced: true, nested: { toJSON: nestedToJSON } },
      key: "a",
      value: false
    },
    {
      holder: { a: false, replaced: true, nested: { toJSON: nestedToJSON } },
      key: "replaced",
      value: true
    },
    {
      holder: { a: false, replaced: true, nested: { toJSON: nestedToJSON } },
      key: "nested",
      value: { nestedToJSONd: true }
    },
    {
      holder: { nestedToJSONd: true },
      key: "nestedToJSONd",
      value: true
    }
  ], stack);

  assertSame(stack[0].holder[""], object);
  assertSame(stack[0].value, toJSONd);
  assertSame(stack[1].holder, replaced);
  assertSame(stack[2].holder, replaced);
  assertSame(stack[3].holder, replaced);
  assertSame(stack[3].value, nestedToJSONd);
  assertSame(stack[4].holder, nestedToJSONd);
})();