text: // Copyright (C) 2022 Igalia, S.L. All rights reserved.
  // This code is governed by the BSD license found in the LICENSE file.
  
  /*---
  esid: sec-temporal.zoneddatetime.prototype.since
  description: Leap second is a valid ISO string for ZonedDateTime
  includes: [temporalHelpers.js]
  features: [Temporal]
  ---*/
  
  const timeZone = new Temporal.TimeZone("UTC");
  const instance = new Temporal.ZonedDateTime(1_483_228_799_000_000_000n, timeZone);
  
  let arg = "2016-12-31T23:59:60+00:00[UTC]";
  const result = instance.since(arg);
  TemporalHelpers.assertDuration(
    result,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    "leap second is a valid ISO string for ZonedDateTime"
  );
  
  arg = "2000-05-02T12:34:56+23:59[+23:59:60]";
  assert.throws(
    RangeError,
    () => instance.since(arg),
    "leap second in time zone name not valid"
  );
  