LibJS: Remove Sign abstract operation

This is an editorial change in the Temporal spec.

See: https://github.com/tc39/proposal-temporal/commit/bbc1ebc

4 files changed, 77 insertions, 109 deletions

diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.cpp
index f3bff4b04e..a36598cdea 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.cpp
@@ -964,36 +964,7 @@ String format_seconds_string_part(u8 second, u16 millisecond, u16 microsecond, u
     return String::formatted("{}.{}", seconds_string, fraction_string);
 }
 
-// 13.27 Sign ( n ), https://tc39.es/proposal-temporal/#sec-temporal-sign
-double sign(double n)
-{
-    // 1. If n is NaN, n is +0𝔽, or n is −0𝔽, return n.
-    if (isnan(n) || n == 0)
-        return n;
-
-    // 2. If n < +0𝔽, return −1𝔽.
-    if (n < 0)
-        return -1;
-
-    // 3. Return 1𝔽.
-    return 1;
-}
-
-double sign(Crypto::SignedBigInteger const& n)
-{
-    // 1. If n is NaN, n is +0𝔽, or n is −0𝔽, return n.
-    if (n == Crypto::SignedBigInteger { 0 })
-        return n.is_negative() ? -0 : 0;
-
-    // 2. If n < +0𝔽, return −1𝔽.
-    if (n.is_negative())
-        return -1;
-
-    // 3. Return 1𝔽.
-    return 1;
-}
-
-// 13.28 ConstrainToRange ( x, minimum, maximum ), https://tc39.es/proposal-temporal/#sec-temporal-constraintorange
+// 13.27 ConstrainToRange ( x, minimum, maximum ), https://tc39.es/proposal-temporal/#sec-temporal-constraintorange
 double constrain_to_range(double x, double minimum, double maximum)
 {
     // 1. Assert: x, minimum and maximum are mathematical values.
@@ -1007,7 +978,7 @@ double constrain_to_range(double x, double minimum, double maximum)
 // it uses mathematical values which can be arbitrarily (but not infinitely) large.
 // Incidentally V8's Temporal implementation does the same :^)
 
-// 13.31 RoundNumberToIncrement ( x, increment, roundingMode ), https://tc39.es/proposal-temporal/#sec-temporal-roundnumbertoincrement
+// 13.30 RoundNumberToIncrement ( x, increment, roundingMode ), https://tc39.es/proposal-temporal/#sec-temporal-roundnumbertoincrement
 i64 round_number_to_increment(double x, u64 increment, StringView rounding_mode)
 {
     // 1. Assert: x and increment are mathematical values.
@@ -1044,7 +1015,7 @@ i64 round_number_to_increment(double x, u64 increment, StringView rounding_mode)
     return (i64)rounded * (i64)increment;
 }
 
-// 13.31 RoundNumberToIncrement ( x, increment, roundingMode ), https://tc39.es/proposal-temporal/#sec-temporal-roundnumbertoincrement
+// 13.30 RoundNumberToIncrement ( x, increment, roundingMode ), https://tc39.es/proposal-temporal/#sec-temporal-roundnumbertoincrement
 BigInt* round_number_to_increment(GlobalObject& global_object, BigInt const& x, u64 increment, StringView rounding_mode)
 {
     auto& heap = global_object.heap();
@@ -1098,7 +1069,7 @@ BigInt* round_number_to_increment(GlobalObject& global_object, BigInt const& x,
     return js_bigint(heap, rounded.multiplied_by(increment_big_int));
 }
 
-// 13.33 ParseISODateTime ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parseisodatetime
+// 13.32 ParseISODateTime ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parseisodatetime
 ThrowCompletionOr<ISODateTime> parse_iso_date_time(GlobalObject& global_object, ParseResult const& parse_result)
 {
     auto& vm = global_object.vm();
@@ -1227,7 +1198,7 @@ ThrowCompletionOr<ISODateTime> parse_iso_date_time(GlobalObject& global_object,
     return ISODateTime { .year = year, .month = month, .day = day, .hour = hour, .minute = minute, .second = second, .millisecond = millisecond, .microsecond = microsecond, .nanosecond = nanosecond, .calendar = Optional<String>(move(calendar_part)) };
 }
 
-// 13.34 ParseTemporalInstantString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalinstantstring
+// 13.33 ParseTemporalInstantString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalinstantstring
 ThrowCompletionOr<TemporalInstant> parse_temporal_instant_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1263,7 +1234,7 @@ ThrowCompletionOr<TemporalInstant> parse_temporal_instant_string(GlobalObject& g
     return TemporalInstant { .year = result.year, .month = result.month, .day = result.day, .hour = result.hour, .minute = result.minute, .second = result.second, .millisecond = result.millisecond, .microsecond = result.microsecond, .nanosecond = result.nanosecond, .time_zone_offset = move(offset_string) };
 }
 
-// 13.35 ParseTemporalZonedDateTimeString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalzoneddatetimestring
+// 13.34 ParseTemporalZonedDateTimeString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalzoneddatetimestring
 ThrowCompletionOr<TemporalZonedDateTime> parse_temporal_zoned_date_time_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1289,7 +1260,7 @@ ThrowCompletionOr<TemporalZonedDateTime> parse_temporal_zoned_date_time_string(G
     return TemporalZonedDateTime { .date_time = move(result), .time_zone = move(time_zone_result) };
 }
 
-// 13.36 ParseTemporalCalendarString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalcalendarstring
+// 13.35 ParseTemporalCalendarString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalcalendarstring
 ThrowCompletionOr<String> parse_temporal_calendar_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1316,7 +1287,7 @@ ThrowCompletionOr<String> parse_temporal_calendar_string(GlobalObject& global_ob
     return id_part.value();
 }
 
-// 13.37 ParseTemporalDateString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaldatestring
+// 13.36 ParseTemporalDateString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaldatestring
 ThrowCompletionOr<TemporalDate> parse_temporal_date_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1343,7 +1314,7 @@ ThrowCompletionOr<TemporalDate> parse_temporal_date_string(GlobalObject& global_
     return TemporalDate { .year = result.year, .month = result.month, .day = result.day, .calendar = move(result.calendar) };
 }
 
-// 13.38 ParseTemporalDateTimeString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaldatetimestring
+// 13.37 ParseTemporalDateTimeString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaldatetimestring
 ThrowCompletionOr<ISODateTime> parse_temporal_date_time_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1367,7 +1338,7 @@ ThrowCompletionOr<ISODateTime> parse_temporal_date_time_string(GlobalObject& glo
     return parse_iso_date_time(global_object, *parse_result);
 }
 
-// 13.39 ParseTemporalDurationString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaldurationstring
+// 13.38 ParseTemporalDurationString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaldurationstring
 ThrowCompletionOr<DurationRecord> parse_temporal_duration_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1509,7 +1480,7 @@ ThrowCompletionOr<DurationRecord> parse_temporal_duration_string(GlobalObject& g
     return create_duration_record(global_object, years * factor, months * factor, weeks * factor, days * factor, hours * factor, floor(minutes) * factor, floor(seconds) * factor, floor(milliseconds) * factor, floor(microseconds) * factor, floor(nanoseconds) * factor);
 }
 
-// 13.40 ParseTemporalMonthDayString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalmonthdaystring
+// 13.39 ParseTemporalMonthDayString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalmonthdaystring
 ThrowCompletionOr<TemporalMonthDay> parse_temporal_month_day_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1545,7 +1516,7 @@ ThrowCompletionOr<TemporalMonthDay> parse_temporal_month_day_string(GlobalObject
     return TemporalMonthDay { .year = year, .month = result.month, .day = result.day, .calendar = move(result.calendar) };
 }
 
-// 13.41 ParseTemporalRelativeToString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalrelativetostring
+// 13.40 ParseTemporalRelativeToString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalrelativetostring
 ThrowCompletionOr<TemporalZonedDateTime> parse_temporal_relative_to_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1594,7 +1565,7 @@ ThrowCompletionOr<TemporalZonedDateTime> parse_temporal_relative_to_string(Globa
     return TemporalZonedDateTime { .date_time = move(result), .time_zone = { .z = z, .offset_string = move(offset_string), .name = move(time_zone) } };
 }
 
-// 13.42 ParseTemporalTimeString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaltimestring
+// 13.41 ParseTemporalTimeString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaltimestring
 ThrowCompletionOr<TemporalTime> parse_temporal_time_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1625,7 +1596,7 @@ ThrowCompletionOr<TemporalTime> parse_temporal_time_string(GlobalObject& global_
     return TemporalTime { .hour = result.hour, .minute = result.minute, .second = result.second, .millisecond = result.millisecond, .microsecond = result.microsecond, .nanosecond = result.nanosecond, .calendar = move(result.calendar) };
 }
 
-// 13.43 ParseTemporalTimeZoneString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaltimezonestring
+// 13.42 ParseTemporalTimeZoneString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaltimezonestring
 ThrowCompletionOr<TemporalTimeZone> parse_temporal_time_zone_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1668,7 +1639,7 @@ ThrowCompletionOr<TemporalTimeZone> parse_temporal_time_zone_string(GlobalObject
     return TemporalTimeZone { .z = false, .offset_string = Optional<String>(move(offset_string)), .name = Optional<String>(move(name)) };
 }
 
-// 13.44 ParseTemporalYearMonthString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalyearmonthstring
+// 13.43 ParseTemporalYearMonthString ( isoString ), https://tc39.es/proposal-temporal/#sec-temporal-parsetemporalyearmonthstring
 ThrowCompletionOr<TemporalYearMonth> parse_temporal_year_month_string(GlobalObject& global_object, String const& iso_string)
 {
     auto& vm = global_object.vm();
@@ -1695,7 +1666,7 @@ ThrowCompletionOr<TemporalYearMonth> parse_temporal_year_month_string(GlobalObje
     return TemporalYearMonth { .year = result.year, .month = result.month, .day = result.day, .calendar = move(result.calendar) };
 }
 
-// 13.45 ToPositiveInteger ( argument ), https://tc39.es/proposal-temporal/#sec-temporal-topositiveinteger
+// 13.44 ToPositiveInteger ( argument ), https://tc39.es/proposal-temporal/#sec-temporal-topositiveinteger
 ThrowCompletionOr<double> to_positive_integer(GlobalObject& global_object, Value argument)
 {
     auto& vm = global_object.vm();
@@ -1713,7 +1684,7 @@ ThrowCompletionOr<double> to_positive_integer(GlobalObject& global_object, Value
     return integer;
 }
 
-// 13.48 PrepareTemporalFields ( fields, fieldNames, requiredFields ), https://tc39.es/proposal-temporal/#sec-temporal-preparetemporalfields
+// 13.47 PrepareTemporalFields ( fields, fieldNames, requiredFields ), https://tc39.es/proposal-temporal/#sec-temporal-preparetemporalfields
 ThrowCompletionOr<Object*> prepare_temporal_fields(GlobalObject& global_object, Object const& fields, Vector<String> const& field_names, Vector<StringView> const& required_fields)
 {
     auto& vm = global_object.vm();
@@ -1764,7 +1735,7 @@ ThrowCompletionOr<Object*> prepare_temporal_fields(GlobalObject& global_object,
     return result;
 }
 
-// 13.49 PreparePartialTemporalFields ( fields, fieldNames ), https://tc39.es/proposal-temporal/#sec-temporal-preparepartialtemporalfields
+// 13.48 PreparePartialTemporalFields ( fields, fieldNames ), https://tc39.es/proposal-temporal/#sec-temporal-preparepartialtemporalfields
 ThrowCompletionOr<Object*> prepare_partial_temporal_fields(GlobalObject& global_object, Object const& fields, Vector<String> const& field_names)
 {
     auto& vm = global_object.vm();
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.h b/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.h
index f54c17c41c..0da3a47421 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.h
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.h
@@ -144,7 +144,7 @@ ThrowCompletionOr<double> to_positive_integer(GlobalObject&, Value argument);
 ThrowCompletionOr<Object*> prepare_temporal_fields(GlobalObject&, Object const& fields, Vector<String> const& field_names, Vector<StringView> const& required_fields);
 ThrowCompletionOr<Object*> prepare_partial_temporal_fields(GlobalObject&, Object const& fields, Vector<String> const& field_names);
 
-// 13.46 ToIntegerThrowOnInfinity ( argument ), https://tc39.es/proposal-temporal/#sec-temporal-tointegerthrowoninfinity
+// 13.45 ToIntegerThrowOnInfinity ( argument ), https://tc39.es/proposal-temporal/#sec-temporal-tointegerthrowoninfinity
 template<typename... Args>
 ThrowCompletionOr<double> to_integer_throw_on_infinity(GlobalObject& global_object, Value argument, ErrorType error_type, Args... args)
 {
@@ -163,7 +163,7 @@ ThrowCompletionOr<double> to_integer_throw_on_infinity(GlobalObject& global_obje
     return integer;
 }
 
-// 13.47 ToIntegerWithoutRounding ( argument ), https://tc39.es/proposal-temporal/#sec-temporal-tointegerwithoutrounding
+// 13.46 ToIntegerWithoutRounding ( argument ), https://tc39.es/proposal-temporal/#sec-temporal-tointegerwithoutrounding
 template<typename... Args>
 ThrowCompletionOr<double> to_integer_without_rounding(GlobalObject& global_object, Value argument, ErrorType error_type, Args... args)
 {
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp
index 01c798e57d..bb672a2117 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp
@@ -1276,32 +1276,28 @@ ThrowCompletionOr<RoundedDuration> round_duration(GlobalObject& global_object, d
         // x. Set days to days - daysPassed.
         days -= days_passed;
 
-        // y. Let sign be ! Sign(days).
-        auto sign = JS::Temporal::sign(days);
+        // y. If days < 0, let sign be −1; else, let sign be 1.
+        auto sign = days < 0 ? -1 : 1;
 
-        // z. If sign is 0, set sign to 1.
-        if (sign == 0)
-            sign = 1;
-
-        // aa. Let oneYear be ? CreateTemporalDuration(sign, 0, 0, 0, 0, 0, 0, 0, 0, 0).
+        // z. Let oneYear be ? CreateTemporalDuration(sign, 0, 0, 0, 0, 0, 0, 0, 0, 0).
         auto* one_year = TRY(create_temporal_duration(global_object, sign, 0, 0, 0, 0, 0, 0, 0, 0, 0));
 
-        // ab. Let moveResult be ? MoveRelativeDate(calendar, relativeTo, oneYear).
+        // aa. Let moveResult be ? MoveRelativeDate(calendar, relativeTo, oneYear).
         auto move_result = TRY(move_relative_date(global_object, *calendar, *relative_to, *one_year));
 
-        // ac. Let oneYearDays be moveResult.[[Days]].
+        // ab. Let oneYearDays be moveResult.[[Days]].
         auto one_year_days = move_result.days;
 
-        // ad. Let fractionalYears be years + days / abs(oneYearDays).
+        // ac. Let fractionalYears be years + days / abs(oneYearDays).
         auto fractional_years = years + days / fabs(one_year_days);
 
-        // ae. Set years to ! RoundNumberToIncrement(fractionalYears, increment, roundingMode).
+        // ad. Set years to ! RoundNumberToIncrement(fractionalYears, increment, roundingMode).
         years = (double)round_number_to_increment(fractional_years, increment, rounding_mode);
 
-        // af. Set remainder to fractionalYears - years.
+        // ae. Set remainder to fractionalYears - years.
         remainder = fractional_years - years;
 
-        // ag. Set months, weeks, and days to 0.
+        // af. Set months, weeks, and days to 0.
         months = 0;
         weeks = 0;
         days = 0;
@@ -1340,26 +1336,22 @@ ThrowCompletionOr<RoundedDuration> round_duration(GlobalObject& global_object, d
         // j. Let days be days + weeksInDays.
         days += weeks_in_days;
 
-        // k. Let sign be ! Sign(days).
-        auto sign = JS::Temporal::sign(days);
-
-        // l. If sign is 0, set sign to 1.
-        if (sign == 0)
-            sign = 1;
+        // k. If days < 0, let sign be −1; else, let sign be 1.
+        auto sign = days < 0 ? -1 : 1;
 
-        // m. Let oneMonth be ? CreateTemporalDuration(0, sign, 0, 0, 0, 0, 0, 0, 0, 0).
+        // l. Let oneMonth be ? CreateTemporalDuration(0, sign, 0, 0, 0, 0, 0, 0, 0, 0).
         auto* one_month = TRY(create_temporal_duration(global_object, 0, sign, 0, 0, 0, 0, 0, 0, 0, 0));
 
-        // n. Let moveResult be ? MoveRelativeDate(calendar, relativeTo, oneMonth).
+        // m. Let moveResult be ? MoveRelativeDate(calendar, relativeTo, oneMonth).
         auto move_result = TRY(move_relative_date(global_object, *calendar, *relative_to, *one_month));
 
-        // o. Set relativeTo to moveResult.[[RelativeTo]].
+        // n. Set relativeTo to moveResult.[[RelativeTo]].
         relative_to = move_result.relative_to.cell();
 
-        // p. Let oneMonthDays be moveResult.[[Days]].
+        // o. Let oneMonthDays be moveResult.[[Days]].
         auto one_month_days = move_result.days;
 
-        // q. Repeat, while abs(days) ≥ abs(oneMonthDays),
+        // p. Repeat, while abs(days) ≥ abs(oneMonthDays),
         while (fabs(days) >= fabs(one_month_days)) {
             // i. Set months to months + sign.
             months += sign;
@@ -1377,16 +1369,16 @@ ThrowCompletionOr<RoundedDuration> round_duration(GlobalObject& global_object, d
             one_month_days = move_result.days;
         }
 
-        // r. Let fractionalMonths be months + days / abs(oneMonthDays).
+        // q. Let fractionalMonths be months + days / abs(oneMonthDays).
         auto fractional_months = months + days / fabs(one_month_days);
 
-        // s. Set months to ! RoundNumberToIncrement(fractionalMonths, increment, roundingMode).
+        // r. Set months to ! RoundNumberToIncrement(fractionalMonths, increment, roundingMode).
         months = (double)round_number_to_increment(fractional_months, increment, rounding_mode);
 
-        // t. Set remainder to fractionalMonths - months.
+        // s. Set remainder to fractionalMonths - months.
         remainder = fractional_months - months;
 
-        // u. Set weeks and days to 0.
+        // t. Set weeks and days to 0.
         weeks = 0;
         days = 0;
     }
@@ -1394,26 +1386,22 @@ ThrowCompletionOr<RoundedDuration> round_duration(GlobalObject& global_object, d
     else if (unit == "week"sv) {
         VERIFY(relative_to);
 
-        // a. Let sign be ! Sign(days).
-        auto sign = JS::Temporal::sign(days);
+        // a. If days < 0, let sign be −1; else, let sign be 1.
+        auto sign = days < 0 ? -1 : 1;
 
-        // b. If sign is 0, set sign to 1.
-        if (sign == 0)
-            sign = 1;
-
-        // c. Let oneWeek be ? CreateTemporalDuration(0, 0, sign, 0, 0, 0, 0, 0, 0, 0).
+        // b. Let oneWeek be ? CreateTemporalDuration(0, 0, sign, 0, 0, 0, 0, 0, 0, 0).
         auto* one_week = TRY(create_temporal_duration(global_object, 0, 0, sign, 0, 0, 0, 0, 0, 0, 0));
 
-        // d. Let moveResult be ? MoveRelativeDate(calendar, relativeTo, oneWeek).
+        // c. Let moveResult be ? MoveRelativeDate(calendar, relativeTo, oneWeek).
         auto move_result = TRY(move_relative_date(global_object, *calendar, *relative_to, *one_week));
 
-        // e. Set relativeTo to moveResult.[[RelativeTo]].
+        // d. Set relativeTo to moveResult.[[RelativeTo]].
         relative_to = move_result.relative_to.cell();
 
-        // f. Let oneWeekDays be moveResult.[[Days]].
+        // e. Let oneWeekDays be moveResult.[[Days]].
         auto one_week_days = move_result.days;
 
-        // g. Repeat, while abs(days) ≥ abs(oneWeekDays),
+        // f. Repeat, while abs(days) ≥ abs(oneWeekDays),
         while (fabs(days) >= fabs(one_week_days)) {
             // i. Set weeks to weeks + sign.
             weeks += sign;
@@ -1431,16 +1419,16 @@ ThrowCompletionOr<RoundedDuration> round_duration(GlobalObject& global_object, d
             one_week_days = move_result.days;
         }
 
-        // h. Let fractionalWeeks be weeks + days / abs(oneWeekDays).
+        // g. Let fractionalWeeks be weeks + days / abs(oneWeekDays).
         auto fractional_weeks = weeks + days / fabs(one_week_days);
 
-        // i. Set weeks to ! RoundNumberToIncrement(fractionalWeeks, increment, roundingMode).
+        // h. Set weeks to ! RoundNumberToIncrement(fractionalWeeks, increment, roundingMode).
         weeks = (double)round_number_to_increment(fractional_weeks, increment, rounding_mode);
 
-        // j. Set remainder to fractionalWeeks - weeks.
+        // i. Set remainder to fractionalWeeks - weeks.
         remainder = fractional_weeks - weeks;
 
-        // k. Set days to 0.
+        // j. Set days to 0.
         days = 0;
     }
     // 13. Else if unit is "day", then
@@ -1569,34 +1557,43 @@ ThrowCompletionOr<DurationRecord> adjust_rounded_duration_days(GlobalObject& glo
     // 2. Let timeRemainderNs be ! TotalDurationNanoseconds(0, hours, minutes, seconds, milliseconds, microseconds, nanoseconds, 0).
     auto time_remainder_ns = total_duration_nanoseconds(global_object, 0, hours, minutes, seconds, milliseconds, microseconds, *js_bigint(vm, Crypto::SignedBigInteger::create_from((i64)nanoseconds)), 0)->big_integer();
 
-    // 3. Let direction be ! ℝ(Sign(𝔽(timeRemainderNs))).
-    auto direction = Temporal::sign(time_remainder_ns);
+    i32 direction;
+
+    // 3. If timeRemainderNs = 0, let direction be 0.
+    if (time_remainder_ns == "0"_bigint)
+        direction = 0;
+    // 4. Else if timeRemainderNs < 0, let direction be −1.
+    else if (time_remainder_ns.is_negative())
+        direction = -1;
+    // 5. Else, let direction be 1.
+    else
+        direction = 1;
 
-    // 4. Let dayStart be ? AddZonedDateTime(relativeTo.[[Nanoseconds]], relativeTo.[[TimeZone]], relativeTo.[[Calendar]], years, months, weeks, days, 0, 0, 0, 0, 0, 0).
+    // 6. Let dayStart be ? AddZonedDateTime(relativeTo.[[Nanoseconds]], relativeTo.[[TimeZone]], relativeTo.[[Calendar]], years, months, weeks, days, 0, 0, 0, 0, 0, 0).
     auto* day_start = TRY(add_zoned_date_time(global_object, relative_to.nanoseconds(), &relative_to.time_zone(), relative_to.calendar(), years, months, weeks, days, 0, 0, 0, 0, 0, 0));
 
-    // 5. Let dayEnd be ? AddZonedDateTime(dayStart, relativeTo.[[TimeZone]], relativeTo.[[Calendar]], 0, 0, 0, direction, 0, 0, 0, 0, 0, 0).
+    // 7. Let dayEnd be ? AddZonedDateTime(dayStart, relativeTo.[[TimeZone]], relativeTo.[[Calendar]], 0, 0, 0, direction, 0, 0, 0, 0, 0, 0).
     auto* day_end = TRY(add_zoned_date_time(global_object, *day_start, &relative_to.time_zone(), relative_to.calendar(), 0, 0, 0, direction, 0, 0, 0, 0, 0, 0));
 
-    // 6. Let dayLengthNs be ℝ(dayEnd − dayStart).
+    // 8. Let dayLengthNs be ℝ(dayEnd − dayStart).
     auto day_length_ns = day_end->big_integer().minus(day_start->big_integer());
 
-    // 7. If (timeRemainderNs − dayLengthNs) × direction < 0, then
-    if (time_remainder_ns.minus(day_length_ns).multiplied_by(Crypto::SignedBigInteger { (i32)direction }).is_negative()) {
+    // 9. If (timeRemainderNs − dayLengthNs) × direction < 0, then
+    if (time_remainder_ns.minus(day_length_ns).multiplied_by(Crypto::SignedBigInteger { direction }).is_negative()) {
         // a. Return ! CreateDurationRecord(years, months, weeks, days, hours, minutes, seconds, milliseconds, microseconds, nanoseconds).
         return create_duration_record(years, months, weeks, days, hours, minutes, seconds, milliseconds, microseconds, nanoseconds);
     }
 
-    // 8. Set timeRemainderNs to ! RoundTemporalInstant(ℤ(timeRemainderNs − dayLengthNs), increment, unit, roundingMode).
+    // 10. Set timeRemainderNs to ! RoundTemporalInstant(ℤ(timeRemainderNs − dayLengthNs), increment, unit, roundingMode).
     time_remainder_ns = round_temporal_instant(global_object, *js_bigint(vm, time_remainder_ns.minus(day_length_ns)), increment, unit, rounding_mode)->big_integer();
 
-    // 9. Let adjustedDateDuration be ? AddDuration(years, months, weeks, days, 0, 0, 0, 0, 0, 0, 0, 0, 0, direction, 0, 0, 0, 0, 0, 0, relativeTo).
+    // 11. Let adjustedDateDuration be ? AddDuration(years, months, weeks, days, 0, 0, 0, 0, 0, 0, 0, 0, 0, direction, 0, 0, 0, 0, 0, 0, relativeTo).
     auto adjusted_date_duration = TRY(add_duration(global_object, years, months, weeks, days, 0, 0, 0, 0, 0, 0, 0, 0, 0, direction, 0, 0, 0, 0, 0, 0, &relative_to));
 
-    // 10. Let adjustedTimeDuration be ? BalanceDuration(0, 0, 0, 0, 0, 0, timeRemainderNs, "hour").
+    // 12. Let adjustedTimeDuration be ? BalanceDuration(0, 0, 0, 0, 0, 0, timeRemainderNs, "hour").
     auto adjusted_time_duration = TRY(balance_duration(global_object, 0, 0, 0, 0, 0, 0, *js_bigint(vm, move(time_remainder_ns)), "hour"sv));
 
-    // 11. Return ! CreateDurationRecord(adjustedDateDuration.[[Years]], adjustedDateDuration.[[Months]], adjustedDateDuration.[[Weeks]], adjustedDateDuration.[[Days]], adjustedTimeDuration.[[Hours]], adjustedTimeDuration.[[Minutes]], adjustedTimeDuration.[[Seconds]], adjustedTimeDuration.[[Milliseconds]], adjustedTimeDuration.[[Microseconds]], adjustedTimeDuration.[[Nanoseconds]]).
+    // 13. Return ! CreateDurationRecord(adjustedDateDuration.[[Years]], adjustedDateDuration.[[Months]], adjustedDateDuration.[[Weeks]], adjustedDateDuration.[[Days]], adjustedTimeDuration.[[Hours]], adjustedTimeDuration.[[Minutes]], adjustedTimeDuration.[[Seconds]], adjustedTimeDuration.[[Milliseconds]], adjustedTimeDuration.[[Microseconds]], adjustedTimeDuration.[[Nanoseconds]]).
     return create_duration_record(adjusted_date_duration.years, adjusted_date_duration.months, adjusted_date_duration.weeks, adjusted_date_duration.days, adjusted_time_duration.hours, adjusted_time_duration.minutes, adjusted_time_duration.seconds, adjusted_time_duration.milliseconds, adjusted_time_duration.microseconds, adjusted_time_duration.nanoseconds);
 }
 
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp
index 77e3a8ce3f..a9cb2fa7d9 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp
@@ -460,18 +460,18 @@ ThrowCompletionOr<NanosecondsToDaysResult> nanoseconds_to_days(GlobalObject& glo
     // 2. Set nanoseconds to ℝ(nanoseconds).
     auto nanoseconds = nanoseconds_bigint.big_integer();
 
-    // 3. Let sign be ! ℝ(Sign(𝔽(nanoseconds))).
-    auto sign = Temporal::sign(nanoseconds);
-
-    // 4. Let dayLengthNs be 8.64 × 10^13.
+    // 3. Let dayLengthNs be 8.64 × 10^13.
     auto day_length_ns = "86400000000000"_sbigint;
 
-    // 5. If sign is 0, then
-    if (sign == 0) {
+    // 4. If nanoseconds = 0, then
+    if (nanoseconds == "0"_bigint) {
         // a. Return the Record { [[Days]]: 0, [[Nanoseconds]]: 0, [[DayLength]]: dayLengthNs }.
         return NanosecondsToDaysResult { .days = 0, .nanoseconds = make_handle(js_bigint(vm, { 0 })), .day_length = day_length_ns.to_double() };
     }
 
+    // 5. If nanoseconds < 0, let sign be −1; else, let sign be 1.
+    auto sign = nanoseconds.is_negative() ? -1 : 1;
+
     // 6. If Type(relativeTo) is not Object or relativeTo does not have an [[InitializedTemporalZonedDateTime]] internal slot, then
     if (!relative_to_value.is_object() || !is<ZonedDateTime>(relative_to_value.as_object())) {
         // a. Return the Record { [[Days]]: the integral part of nanoseconds / dayLengthNs, [[Nanoseconds]]: (abs(nanoseconds) modulo dayLengthNs) × sign, [[DayLength]]: dayLengthNs }.