LibJS: Reject '-000000' as extended year

This is a normative change in the Temporal spec.

See: https://github.com/tc39/proposal-temporal/commit/e60ef9e

Userland/Libraries/LibJS/Runtime/ErrorTypes.h

@@ -232,6 +232,7 @@
     M(TemporalInvalidDurationString, "Invalid duration string '{}'")                                                                    \
     M(TemporalInvalidDurationStringFractionNotLast, "Invalid duration string '{}': fractional {} must not be proceeded by {}")          \
     M(TemporalInvalidEpochNanoseconds, "Invalid epoch nanoseconds value, must be in range -86400 * 10^17 to 86400 * 10^17")             \
+    M(TemporalInvalidExtendedYearNegativeZero, "Invalid extended year, must not be negative zero")                                      \
     M(TemporalInvalidInstantString, "Invalid instant string '{}'")                                                                      \
     M(TemporalInvalidISODate, "Invalid ISO date")                                                                                       \
     M(TemporalInvalidMonthCode, "Invalid month code")                                                                                   \

Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.cpp

@@ -1142,43 +1142,47 @@ ThrowCompletionOr<ISODateTime> parse_iso_date_time(GlobalObject& global_object,
     else
         normalized_year = year_part.value_or("0");
 
-    // 7. Set year to ! ToIntegerOrInfinity(year).
+    // 7. If ! SameValue(year, "-000000") is true, throw a RangeError exception.
+    if (normalized_year == "-000000"sv)
+        return vm.throw_completion<RangeError>(global_object, ErrorType::TemporalInvalidExtendedYearNegativeZero);
+
+    // 8. Set year to ! ToIntegerOrInfinity(year).
     auto year = *normalized_year.to_int<i32>();
 
     u8 month;
-    // 8. If month is undefined, then
+    // 9. If month is undefined, then
     if (!month_part.has_value()) {
         // a. Set month to 1.
         month = 1;
     }
-    // 9. Else,
+    // 10. Else,
     else {
         // a. Set month to ! ToIntegerOrInfinity(month).
         month = *month_part->to_uint<u8>();
     }
 
     u8 day;
-    // 10. If day is undefined, then
+    // 11. If day is undefined, then
     if (!day_part.has_value()) {
         // a. Set day to 1.
         day = 1;
     }
-    // 11. Else,
+    // 12. Else,
     else {
         // a. Set day to ! ToIntegerOrInfinity(day).
         day = *day_part->to_uint<u8>();
     }
 
-    // 12. Set hour to ! ToIntegerOrInfinity(hour).
+    // 13. Set hour to ! ToIntegerOrInfinity(hour).
     u8 hour = *hour_part.value_or("0"sv).to_uint<u8>();
 
-    // 13. Set minute to ! ToIntegerOrInfinity(minute).
+    // 14. Set minute to ! ToIntegerOrInfinity(minute).
     u8 minute = *minute_part.value_or("0"sv).to_uint<u8>();
 
-    // 14. Set second to ! ToIntegerOrInfinity(second).
+    // 15. Set second to ! ToIntegerOrInfinity(second).
     u8 second = *second_part.value_or("0"sv).to_uint<u8>();
 
-    // 15. If second is 60, then
+    // 16. If second is 60, then
     if (second == 60) {
         // a. Set second to 59.
         second = 59;
@@ -1187,7 +1191,7 @@ ThrowCompletionOr<ISODateTime> parse_iso_date_time(GlobalObject& global_object,
     u16 millisecond;
     u16 microsecond;
     u16 nanosecond;
-    // 16. If fraction is not undefined, then
+    // 17. If fraction is not undefined, then
     if (fraction_part.has_value()) {
         // a. Set fraction to the string-concatenation of the previous value of fraction and the string "000000000".
         auto fraction = String::formatted("{}000000000", *fraction_part);
@@ -1201,7 +1205,7 @@ ThrowCompletionOr<ISODateTime> parse_iso_date_time(GlobalObject& global_object,
         // g. Set nanosecond to ! ToIntegerOrInfinity(nanosecond).
         nanosecond = *fraction.substring(7, 3).to_uint<u16>();
     }
-    // 17. Else,
+    // 18. Else,
     else {
         // a. Let millisecond be 0.
         millisecond = 0;
@@ -1211,15 +1215,15 @@ ThrowCompletionOr<ISODateTime> parse_iso_date_time(GlobalObject& global_object,
         nanosecond = 0;
     }
 
-    // 18. If ! IsValidISODate(year, month, day) is false, throw a RangeError exception.
+    // 19. If ! IsValidISODate(year, month, day) is false, throw a RangeError exception.
     if (!is_valid_iso_date(year, month, day))
         return vm.throw_completion<RangeError>(global_object, ErrorType::TemporalInvalidISODate);
 
-    // 19. If ! IsValidTime(hour, minute, second, millisecond, microsecond, nanosecond) is false, throw a RangeError exception.
+    // 20. If ! IsValidTime(hour, minute, second, millisecond, microsecond, nanosecond) is false, throw a RangeError exception.
     if (!is_valid_time(hour, minute, second, millisecond, microsecond, nanosecond))
         return vm.throw_completion<RangeError>(global_object, ErrorType::TemporalInvalidTime);
 
-    // 20. Return the Record { [[Year]]: year, [[Month]]: month, [[Day]]: day, [[Hour]]: hour, [[Minute]]: minute, [[Second]]: second, [[Millisecond]]: millisecond, [[Microsecond]]: microsecond, [[Nanosecond]]: nanosecond, [[Calendar]]: calendar }.
+    // 21. Return the Record { [[Year]]: year, [[Month]]: month, [[Day]]: day, [[Hour]]: hour, [[Minute]]: minute, [[Second]]: second, [[Millisecond]]: millisecond, [[Microsecond]]: microsecond, [[Nanosecond]]: nanosecond, [[Calendar]]: calendar }.
     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)) };
 }
 
@@ -1678,16 +1682,24 @@ ThrowCompletionOr<TemporalYearMonth> parse_temporal_year_month_string(GlobalObje
         return vm.throw_completion<RangeError>(global_object, ErrorType::TemporalInvalidYearMonthString, iso_string);
     }
 
-    // 3. If isoString contains a UTCDesignator, then
+    // FIXME: I don't think this check makes sense - the TemporalYearMonthString syntax check above
+    //        should rule out a string that's '-000000'; it requires a month with a non-zero digit
+    //        in it, and the normalized year is checked separately in ParseISODateTime below.
+    //        :yakshrug:
+    // 3. If ! SameValue(isoString, "-000000") is true, throw a RangeError exception.
+    if (iso_string == "-000000"sv)
+        return vm.throw_completion<RangeError>(global_object, ErrorType::TemporalInvalidExtendedYearNegativeZero);
+
+    // 4. If isoString contains a UTCDesignator, then
     if (parse_result->utc_designator.has_value()) {
         // a. Throw a RangeError exception.
         return vm.throw_completion<RangeError>(global_object, ErrorType::TemporalInvalidYearMonthStringUTCDesignator, iso_string);
     }
 
-    // 4. Let result be ? ParseISODateTime(isoString).
+    // 5. Let result be ? ParseISODateTime(isoString).
     auto result = TRY(parse_iso_date_time(global_object, *parse_result));
 
-    // 5. Return the Record { [[Year]]: result.[[Year]], [[Month]]: result.[[Month]], [[Day]]: result.[[Day]], [[Calendar]]: result.[[Calendar]] }.
+    // 6. Return the Record { [[Year]]: result.[[Year]], [[Month]]: result.[[Month]], [[Day]]: result.[[Day]], [[Calendar]]: result.[[Calendar]] }.
     return TemporalYearMonth { .year = result.year, .month = result.month, .day = result.day, .calendar = move(result.calendar) };
 }
 

Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.from.js

@@ -49,4 +49,10 @@ describe("errors", () => {
             Temporal.PlainDate.from("foo");
         }).toThrowWithMessage(RangeError, "Invalid date string 'foo'");
     });
+
+    test("extended year must not be negative zero", () => {
+        expect(() => {
+            Temporal.PlainDate.from("-000000-01-01");
+        }).toThrowWithMessage(RangeError, "Invalid extended year, must not be negative zero");
+    });
 });

Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDateTime/PlainDateTime.from.js

@@ -186,4 +186,10 @@ describe("errors", () => {
             "Invalid date time string '2021-07-06T23:42:01Z': must not contain a UTC designator"
         );
     });
+
+    test("extended year must not be negative zero", () => {
+        expect(() => {
+            Temporal.PlainDateTime.from("-000000-01-01");
+        }).toThrowWithMessage(RangeError, "Invalid extended year, must not be negative zero");
+    });
 });

Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainMonthDay/PlainMonthDay.from.js

@@ -75,4 +75,10 @@ describe("errors", () => {
             "Invalid month day string '2021-07-06T23:42:01Z': must not contain a UTC designator"
         );
     });
+
+    test("extended year must not be negative zero", () => {
+        expect(() => {
+            Temporal.PlainMonthDay.from("-000000-01-01");
+        }).toThrowWithMessage(RangeError, "Invalid extended year, must not be negative zero");
+    });
 });

Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.from.js

@@ -65,6 +65,12 @@ describe("errors", () => {
         );
     });
 
+    test("extended year must not be negative zero", () => {
+        expect(() => {
+            Temporal.PlainTime.from("-000000-01-01T00:00:00");
+        }).toThrowWithMessage(RangeError, "Invalid extended year, must not be negative zero");
+    });
+
     test("ambiguous string must contain a time designator", () => {
         const values = [
             // YYYY-MM or HHMM-UU

Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainYearMonth/PlainYearMonth.from.js

@@ -101,4 +101,10 @@ describe("errors", () => {
             "Invalid year month string '2021-07-06T23:42:01Z': must not contain a UTC designator"
         );
     });
+
+    test("extended year must not be negative zero", () => {
+        expect(() => {
+            Temporal.PlainYearMonth.from("-000000-01");
+        }).toThrowWithMessage(RangeError, "Invalid extended year, must not be negative zero");
+    });
 });