1 var $ = require('../internals/export');
2 var global = require('../internals/global');
3 var getBuiltIn = require('../internals/get-built-in');
4 var apply = require('../internals/function-apply');
5 var uncurryThis = require('../internals/function-uncurry-this');
6 var fails = require('../internals/fails');
8 var Array = global.Array;
9 var $stringify = getBuiltIn('JSON', 'stringify');
10 var exec = uncurryThis(/./.exec);
11 var charAt = uncurryThis(''.charAt);
12 var charCodeAt = uncurryThis(''.charCodeAt);
13 var replace = uncurryThis(''.replace);
14 var numberToString = uncurryThis(1.0.toString);
16 var tester = /[\uD800-\uDFFF]/g;
17 var low = /^[\uD800-\uDBFF]$/;
18 var hi = /^[\uDC00-\uDFFF]$/;
20 var fix = function (match, offset, string) {
21 var prev = charAt(string, offset - 1);
22 var next = charAt(string, offset + 1);
23 if ((exec(low, match) && !exec(hi, next)) || (exec(hi, match) && !exec(low, prev))) {
24 return '\\u' + numberToString(charCodeAt(match, 0), 16);
28 var FORCED = fails(function () {
29 return $stringify('\uDF06\uD834') !== '"\\udf06\\ud834"'
30 || $stringify('\uDEAD') !== '"\\udead"';
34 // `JSON.stringify` method
35 // https://tc39.es/ecma262/#sec-json.stringify
36 // https://github.com/tc39/proposal-well-formed-stringify
37 $({ target: 'JSON', stat: true, forced: FORCED }, {
38 // eslint-disable-next-line no-unused-vars -- required for `.length`
39 stringify: function stringify(it, replacer, space) {
40 for (var i = 0, l = arguments.length, args = Array(l); i < l; i++) args[i] = arguments[i];
41 var result = apply($stringify, null, args);
42 return typeof result == 'string' ? replace(result, tester, fix) : result;