--- /dev/null
+'use strict';
+var $ = require('../internals/export');
+var fails = require('../internals/fails');
+var toObject = require('../internals/to-object');
+var toPrimitive = require('../internals/to-primitive');
+
+var FORCED = fails(function () {
+ return new Date(NaN).toJSON() !== null
+ || Date.prototype.toJSON.call({ toISOString: function () { return 1; } }) !== 1;
+});
+
+// `Date.prototype.toJSON` method
+// https://tc39.es/ecma262/#sec-date.prototype.tojson
+$({ target: 'Date', proto: true, forced: FORCED }, {
+ // eslint-disable-next-line no-unused-vars -- required for `.length`
+ toJSON: function toJSON(key) {
+ var O = toObject(this);
+ var pv = toPrimitive(O);
+ return typeof pv == 'number' && !isFinite(pv) ? null : O.toISOString();
+ }
+});