securityos/node_modules/es-abstract/2023/TimeZoneString.js

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2024-09-06 15:32:35 +00:00
'use strict';
var GetIntrinsic = require('get-intrinsic');
var $Date = GetIntrinsic('%Date%');
var $TypeError = require('es-errors/type');
var isInteger = require('../helpers/isInteger');
var callBound = require('call-bind/callBound');
var $indexOf = callBound('String.prototype.indexOf');
var $slice = callBound('String.prototype.slice');
var $toTimeString = callBound('Date.prototype.toTimeString');
// https://262.ecma-international.org/14.0/#sec-timezoneestring
module.exports = function TimeZoneString(tv) {
if (!isInteger(tv)) {
throw new $TypeError('Assertion failed: `tv` must be an integral Number');
}
// 1. Let localTimeZone be DefaultTimeZone().
// 2. If IsTimeZoneOffsetString(localTimeZone) is true, then
// a. Let offsetNs be ParseTimeZoneOffsetString(localTimeZone).
// 3. Else,
// a. Let offsetNs be GetNamedTimeZoneOffsetNanoseconds(localTimeZone, ((tv) × 106)).
// 4. Let offset be 𝔽(truncate(offsetNs / 106)).
// 5. If offset is +0𝔽 or offset > +0𝔽, then
// a. Let offsetSign be "+".
// b. Let absOffset be offset.
// 6. Else,
// a. Let offsetSign be "-".
// b. Let absOffset be -offset.
// 7. Let offsetMin be ToZeroPaddedDecimalString((MinFromTime(absOffset)), 2).
// 8. Let offsetHour be ToZeroPaddedDecimalString((HourFromTime(absOffset)), 2).
// 9. Let tzName be an implementation-defined string that is either the empty String or the string-concatenation of the code unit 0x0020 (SPACE), the code unit 0x0028 (LEFT PARENTHESIS), an implementation-defined timezone name, and the code unit 0x0029 (RIGHT PARENTHESIS).
// 10. Return the string-concatenation of offsetSign, offsetHour, offsetMin, and tzName.
// hack until DefaultTimeZone, IsTimeZoneOffsetString, ParseTimeZoneOffsetString, GetNamedTimeZoneOffsetNanoseconds, and "implementation-defined string" are available
var ts = $toTimeString(new $Date(tv));
return $slice(ts, $indexOf(ts, '(') + 1, $indexOf(ts, ')'));
};