LibJS: Implement the Temporal.PlainMonthDay constructor

And the simple Temporal.PlainMonthDay.prototype getters, so that the constructed Temporal.PlainMonthDay may actually be validated.
Author: https://github.com/trflynn89 Commit: 1a386e78c3 Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2471
2025-08-16 15:30:09 +00:00 · 2024-11-20 12:59:15 -05:00 · 2024-11-20 12:59:15 -05:00 · 1a386e78c3 · 2024-11-22 00:25:44 +00:00
commit 1a386e78c3
parent b3b968bed9
31 changed files with 2515 additions and 4 deletions
--- a/Libraries/LibJS/Runtime/Temporal/PlainMonthDay.cpp
+++ b/Libraries/LibJS/Runtime/Temporal/PlainMonthDay.cpp
@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2021-2023, Linus Groh <linusg@serenityos.org>
+ * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
+ * Copyright (c) 2024, Tim Flynn <trflynn89@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/AbstractOperations.h>
+#include <LibJS/Runtime/Intrinsics.h>
+#include <LibJS/Runtime/Realm.h>
+#include <LibJS/Runtime/Temporal/AbstractOperations.h>
+#include <LibJS/Runtime/Temporal/Calendar.h>
+#include <LibJS/Runtime/Temporal/PlainMonthDay.h>
+#include <LibJS/Runtime/Temporal/PlainMonthDayConstructor.h>
+#include <LibJS/Runtime/VM.h>
+
+namespace JS::Temporal {
+
+GC_DEFINE_ALLOCATOR(PlainMonthDay);
+
+// 10 Temporal.PlainMonthDay Objects, https://tc39.es/proposal-temporal/#sec-temporal-plainmonthday-objects
+PlainMonthDay::PlainMonthDay(ISODate iso_date, String calendar, Object& prototype)
+    : Object(ConstructWithPrototypeTag::Tag, prototype)
+    , m_iso_date(iso_date)
+    , m_calendar(move(calendar))
+{
+}
+
+// 10.5.1 ToTemporalMonthDay ( item [ , options ] ), https://tc39.es/proposal-temporal/#sec-temporal-totemporalmonthday
+ThrowCompletionOr<GC::Ref<PlainMonthDay>> to_temporal_month_day(VM& vm, Value item, Value options)
+{
+    // 1. If options is not present, set options to undefined.
+
+    // 2. If item is a Object, then
+    if (item.is_object()) {
+        auto const& object = item.as_object();
+
+        // a. If item has an [[InitializedTemporalMonthDay]] internal slot, then
+        if (is<PlainMonthDay>(object)) {
+            auto const& plain_month_day = static_cast<PlainMonthDay const&>(object);
+
+            // i. Let resolvedOptions be ? GetOptionsObject(options).
+            auto resolved_options = TRY(get_options_object(vm, options));
+
+            // ii. Perform ? GetTemporalOverflowOption(resolvedOptions).
+            TRY(get_temporal_overflow_option(vm, resolved_options));
+
+            // iii. Return ! CreateTemporalMonthDay(item.[[ISODate]], item.[[Calendar]]).
+            return MUST(create_temporal_month_day(vm, plain_month_day.iso_date(), plain_month_day.calendar()));
+        }
+
+        // b. Let calendar be ? GetTemporalCalendarIdentifierWithISODefault(item).
+        auto calendar = TRY(get_temporal_calendar_identifier_with_iso_default(vm, object));
+
+        // c. Let fields be ? PrepareCalendarFields(calendar, item, « YEAR, MONTH, MONTH-CODE, DAY », «», «»).
+        auto fields = TRY(prepare_calendar_fields(vm, calendar, object, { { CalendarField::Year, CalendarField::Month, CalendarField::MonthCode, CalendarField::Day } }, {}, CalendarFieldList {}));
+
+        // d. Let resolvedOptions be ? GetOptionsObject(options).
+        auto resolved_options = TRY(get_options_object(vm, options));
+
+        // e. Let overflow be ? GetTemporalOverflowOption(resolvedOptions).
+        auto overflow = TRY(get_temporal_overflow_option(vm, resolved_options));
+
+        // f. Let isoDate be ? CalendarMonthDayFromFields(calendar, fields, overflow).
+        auto iso_date = TRY(calendar_month_day_from_fields(vm, calendar, move(fields), overflow));
+
+        // g. Return ! CreateTemporalMonthDay(isoDate, calendar).
+        return MUST(create_temporal_month_day(vm, iso_date, move(calendar)));
+    }
+
+    // 3. If item is not a String, throw a TypeError exception.
+    if (!item.is_string())
+        return vm.throw_completion<TypeError>(ErrorType::TemporalInvalidPlainMonthDay);
+
+    // 4. Let result be ? ParseISODateTime(item, « TemporalMonthDayString »).
+    auto parse_result = TRY(parse_iso_date_time(vm, item.as_string().utf8_string_view(), { { Production::TemporalMonthDayString } }));
+
+    // 5. Let calendar be result.[[Calendar]].
+    // 6. If calendar is empty, set calendar to "iso8601".
+    auto calendar = parse_result.calendar.value_or("iso8601"_string);
+
+    // 7. Set calendar to ? CanonicalizeCalendar(calendar).
+    calendar = TRY(canonicalize_calendar(vm, calendar));
+
+    // 8. Let resolvedOptions be ? GetOptionsObject(options).
+    auto resolved_options = TRY(get_options_object(vm, options));
+
+    // 9. Perform ? GetTemporalOverflowOption(resolvedOptions).
+    TRY(get_temporal_overflow_option(vm, resolved_options));
+
+    // 10. If result.[[Year]] is empty, then
+    if (!parse_result.year.has_value()) {
+        // a. Assert: calendar is "iso8601".
+        VERIFY(calendar == "iso8601"sv);
+
+        // b. Let referenceISOYear be 1972 (the first ISO 8601 leap year after the epoch).
+        static constexpr i32 reference_iso_year = 1972;
+
+        // c. Let isoDate be CreateISODateRecord(referenceISOYear, result.[[Month]], result.[[Day]]).
+        auto iso_date = create_iso_date_record(reference_iso_year, parse_result.month, parse_result.day);
+
+        // d. Return ! CreateTemporalMonthDay(isoDate, calendar).
+        return MUST(create_temporal_month_day(vm, iso_date, move(calendar)));
+    }
+
+    // 11. Let isoDate be CreateISODateRecord(result.[[Year]], result.[[Month]], result.[[Day]]).
+    auto iso_date = create_iso_date_record(*parse_result.year, parse_result.month, parse_result.day);
+
+    // 12. Set result to ISODateToFields(calendar, isoDate, MONTH-DAY).
+    auto result = iso_date_to_fields(calendar, iso_date, DateType::MonthDay);
+
+    // 13. NOTE: The following operation is called with CONSTRAIN regardless of the value of overflow, in order for the
+    //     calendar to store a canonical value in the [[Year]] field of the [[ISODate]] internal slot of the result.
+    // 14. Set isoDate to ? CalendarMonthDayFromFields(calendar, result, CONSTRAIN).
+    iso_date = TRY(calendar_month_day_from_fields(vm, calendar, result, Overflow::Constrain));
+
+    // 15. Return ! CreateTemporalMonthDay(isoDate, calendar).
+    return MUST(create_temporal_month_day(vm, iso_date, move(calendar)));
+}
+
+// 10.5.2 CreateTemporalMonthDay ( isoDate, calendar [ , newTarget ] ), https://tc39.es/proposal-temporal/#sec-temporal-createtemporalmonthday
+ThrowCompletionOr<GC::Ref<PlainMonthDay>> create_temporal_month_day(VM& vm, ISODate iso_date, String calendar, GC::Ptr<FunctionObject> new_target)
+{
+    auto& realm = *vm.current_realm();
+
+    // 1. If ISODateWithinLimits(isoDate) is false, throw a RangeError exception.
+    if (!iso_date_within_limits(iso_date))
+        return vm.throw_completion<RangeError>(ErrorType::TemporalInvalidPlainMonthDay);
+
+    // 2. If newTarget is not present, set newTarget to %Temporal.PlainMonthDay%.
+    if (!new_target)
+        new_target = realm.intrinsics().temporal_plain_month_day_constructor();
+
+    // 3. Let object be ? OrdinaryCreateFromConstructor(newTarget, "%Temporal.PlainMonthDay.prototype%", « [[InitializedTemporalMonthDay]], [[ISODate]], [[Calendar]] »).
+    // 4. Set object.[[ISODate]] to isoDate.
+    // 5. Set object.[[Calendar]] to calendar.
+    auto object = TRY(ordinary_create_from_constructor<PlainMonthDay>(vm, *new_target, &Intrinsics::temporal_plain_month_day_prototype, iso_date, move(calendar)));
+
+    // 6. Return object.
+    return object;
+}
+
+}