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// |reftest| skip-if(!this.hasOwnProperty('Temporal')) -- Temporal is not enabled unconditionally
// Copyright (C) 2026 Igalia, S.L. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-temporal.plainmonthday.from
features: [Temporal, Intl.Era-monthcode]
description: Check that reference years are correct in situations where user provides a year
---*/
// All of these should coerce to the equivalent day in the non-leap version of the month
// The years in entries of `plainDateCandidates` are the ones yielded by 1. ICU4X's
// algorithm and 2. ICU4C's algorithm. When creating a PlainDate and `overflow`
// is not `"reject"` it should be possible to actually create one or the other of these sets of
// PlainDates, depending on which library is used.
// Moreover, it should be possible to create a PlainMonthDay from the year, month, and day used
// to create these valid PlainDates, if in this call `overflow` is likewise not `"reject"`.
const plainDateCandidates = [
// ICU4X years
{ year: 1651, monthCode: "M01L", day: 29, referenceYear: 1972 },
{ year: 1461, monthCode: "M01L", day: 30, referenceYear: 1970 },
{ year: 1765, monthCode: "M02L", day: 30, referenceYear: 1972 },
{ year: 1718, monthCode: "M08L", day: 30, referenceYear: 1971 },
{ year: -5738, monthCode: "M09L", day: 30, referenceYear: 1972 },
{ year: -4098, monthCode: "M10L", day: 30, referenceYear: 1972 },
{ year: -2173, monthCode: "M11L", day: 30, referenceYear: 1970 },
{ year: 1403, monthCode: "M12L", day: 29, referenceYear: 1972 },
{ year: -180, monthCode: "M12L", day: 30, referenceYear: 1972 },
// ICU4C years
{ year: 1898, monthCode: "M01L", day: 29, referenceYear: 1972 },
{ year: 1898, monthCode: "M01L", day: 30, referenceYear: 1970 },
{ year: 1830, monthCode: "M02L", day: 30, referenceYear: 1972 },
{ year: 1718, monthCode: "M08L", day: 30, referenceYear: 1971 },
{ year: 1843, monthCode: "M09L", day: 30, referenceYear: 1972 },
{ year: 1737, monthCode: "M10L", day: 30, referenceYear: 1972 },
{ year: 1889, monthCode: "M11L", day: 30, referenceYear: 1970 },
{ year: 1879, monthCode: "M12L", day: 29, referenceYear: 1972 },
{ year: 1784, monthCode: "M12L", day: 30, referenceYear: 1972 },
];
const calendars = ["chinese", "dangi"];
for (const calendar of calendars){
for (const {year, monthCode, day, referenceYear} of plainDateCandidates){
const pd = Temporal.PlainDate.from({ calendar, year, monthCode, day });
if (pd.monthCode === monthCode && pd.day === day){
const pmd = Temporal.PlainMonthDay.from({calendar, year, monthCode, day});
const pmdYear = Number(pmd.toString().split("-")[0]);
assert.sameValue(pmdYear, referenceYear, `reference year for ${year} ${monthCode} ${day} is ${pmdYear}, should be ${referenceYear}`);
const pmdFromPd = pd.toPlainMonthDay();
const pmdFromPdYear = Number(pmdFromPd.toString().split("-")[0]);
assert.sameValue(pmdFromPdYear, referenceYear, `reference year for ${year} ${monthCode} ${day} is ${pmdYear}, should be ${referenceYear}`);
}
}
}
reportCompare(0, 0);