packages/core-js/modules/es.date.to-string.js

'use strict';
// TODO: Remove from `core-js@4`
var uncurryThis = require('../internals/function-uncurry-this');
var defineBuiltIn = require('../internals/define-built-in');

var DatePrototype = Date.prototype;
var INVALID_DATE = 'Invalid Date';
var TO_STRING = 'toString';
var nativeDateToString = uncurryThis(DatePrototype[TO_STRING]);
var thisTimeValue = uncurryThis(DatePrototype.getTime);

// `Date.prototype.toString` method
// https://tc39.es/ecma262/#sec-date.prototype.tostring
if (String(new Date(NaN)) !== INVALID_DATE) {
  defineBuiltIn(DatePrototype, TO_STRING, function toString() {
    var value = thisTimeValue(this);
    // eslint-disable-next-line no-self-compare -- NaN check
    return value === value ? nativeDateToString(this) : INVALID_DATE;
  });
}