2 var $ = require('../internals/export');
3 var fails = require('../internals/fails');
4 var toObject = require('../internals/to-object');
5 var toPrimitive = require('../internals/to-primitive');
7 var FORCED = fails(function () {
8 return new Date(NaN).toJSON() !== null
9 || Date.prototype.toJSON.call({ toISOString: function () { return 1; } }) !== 1;
12 // `Date.prototype.toJSON` method
13 // https://tc39.es/ecma262/#sec-date.prototype.tojson
14 $({ target: 'Date', proto: true, forced: FORCED }, {
15 // eslint-disable-next-line no-unused-vars -- required for `.length`
16 toJSON: function toJSON(key) {
17 var O = toObject(this);
18 var pv = toPrimitive(O, 'number');
19 return typeof pv == 'number' && !isFinite(pv) ? null : O.toISOString();