tor-browser

commit 37099145c6fbabf605808a45ce1cec792d7b25c9
parent b2239a2304b0cb1ce21718cd19095b5a5971fa6f
Author: André Bargull <andre.bargull@gmail.com>
Date:   Fri, 12 Dec 2025 10:54:20 +0000

Bug 2005482: Constrain day before calling CreateDateFromCodes with overflow=reject for Hebrew calendar. r=spidermonkey-reviewers,dminor

Constrain the input `day` before calling `CreateDateFromCodes` when
`overflow=reject` to avoid incorrectly rejecting dates. When the day was
constrained, handle `overflow=reject` through an explicit check using
`CalendarDaysInMonth`.

This case is specific to the Hebrew calendar and can't happen for Chinese/Dangi
calendars, because all Chinese/Dangi months have the same number of minimum resp.
maximum days per month.

Differential Revision: https://phabricator.services.mozilla.com/D275957

Diffstat:
M
js/src/builtin/temporal/Calendar.cpp
 | 
29
++++++++++++++++++++++++++++-
A
js/src/tests/non262/Temporal/PlainDate/hebrew-from-ordinal-month.js
 | 
69
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 97 insertions(+), 1 deletion(-)
diff --git a/js/src/builtin/temporal/Calendar.cpp b/js/src/builtin/temporal/Calendar.cpp
@@ -1338,10 +1338,25 @@ static UniqueICU4XDate CreateDateFrom(JSContext* cx, CalendarId calendarId,
 
       MOZ_ASSERT(1 <= month && month <= 13);
 
+      // Constrain |day| when overflow is "reject" to avoid rejecting too large
+      // day values in CreateDateFromCodes.
+      //
+      // For example when month = 10 and day = 30 and the input year is a leap
+      // year. We first try month code "M10", but since "M10" can have at most
+      // 29 days, we need to constrain the days value before calling
+      // CreateDateFromCodes.
+      int32_t constrainedDay = day;
+      if (overflow == TemporalOverflow::Reject) {
+        constexpr auto daysInMonth = CalendarDaysInMonth(CalendarId::Hebrew);
+        if (day > daysInMonth.first && day <= daysInMonth.second) {
+          constrainedDay = daysInMonth.first;
+        }
+      }
+
       // Create date with month number replaced by month-code.
       auto monthCode = MonthCode{std::min(month, 12)};
       auto date = CreateDateFromCodes(cx, calendarId, calendar, eraYear,
-                                      monthCode, day, overflow);
+                                      monthCode, constrainedDay, overflow);
       if (!date) {
         return nullptr;
       }
@@ -1350,6 +1365,18 @@ static UniqueICU4XDate CreateDateFrom(JSContext* cx, CalendarId calendarId,
       // changes are necessary and we can directly return |date|.
       int32_t ordinal = OrdinalMonth(date.get());
       if (ordinal == month) {
+        // If |day| was constrained, check if the actual input days value
+        // exceeds the number of days in the resolved month.
+        if (constrainedDay < day) {
+          MOZ_ASSERT(overflow == TemporalOverflow::Reject);
+
+          if (day > CalendarDaysInMonth(calendarId, monthCode).second) {
+            ReportCalendarFieldOverflow(cx, "day", day);
+            return nullptr;
+          }
+          return CreateDateFromCodes(cx, calendarId, calendar, eraYear,
+                                     monthCode, day, overflow);
+        }
         return date;
       }
 
diff --git a/js/src/tests/non262/Temporal/PlainDate/hebrew-from-ordinal-month.js b/js/src/tests/non262/Temporal/PlainDate/hebrew-from-ordinal-month.js
@@ -0,0 +1,69 @@
+// |reftest| skip-if(!this.hasOwnProperty("Temporal"))
+
+const calendar = "hebrew";
+
+function assertDate(actual, {year, month, monthCode, day}) {
+  assertEq(actual.year, year);
+  assertEq(actual.month, month);
+  assertEq(actual.monthCode, monthCode);
+  assertEq(actual.day, day);
+}
+
+// 5783 is a common year.
+const commonYear = 5783;
+
+// 5784 is a leap year.
+const leapYear = 5784;
+
+// Test common and leap years.
+for (let year of [commonYear, leapYear]) {
+  let firstDayOfYear = Temporal.PlainDate.from({calendar, year, monthCode: "M01", day: 1});
+  assertEq(firstDayOfYear.inLeapYear, (year === leapYear));
+
+  let monthsInYear = firstDayOfYear.monthsInYear;
+  assertEq(monthsInYear, 12 + firstDayOfYear.inLeapYear);
+
+  // Test for each month in the year.
+  for (let month = 1; month <= monthsInYear; ++month) {
+    let firstDayOfMonthFromOrdinalMonth = Temporal.PlainDate.from({calendar, year, month, day: 1});
+    let monthCode = firstDayOfMonthFromOrdinalMonth.monthCode;
+    assertDate(firstDayOfMonthFromOrdinalMonth, {year, month, monthCode, day: 1});
+
+    let firstDayOfMonthFromMonthCode = Temporal.PlainDate.from({calendar, year, monthCode, day: 1});
+    assertDate(firstDayOfMonthFromMonthCode, {year, month, monthCode, day: 1});
+
+    // 29-30 days for each month.
+    let daysInMonth = firstDayOfMonthFromOrdinalMonth.daysInMonth;
+    assertEq(29 <= daysInMonth && daysInMonth <= 30 , true);
+
+    // Test for each day of the month.
+    for (let day = 2; day <= daysInMonth; ++day) {
+      for (let overflow of ["constrain", "reject"]) {
+        let fromOrdinalMonth = Temporal.PlainDate.from({calendar, year, month, day}, {overflow});
+        assertDate(fromOrdinalMonth, {year, month, monthCode, day});
+
+        let fromMonthCode = Temporal.PlainDate.from({calendar, year, monthCode, day}, {overflow});
+        assertDate(fromMonthCode, {year, month, monthCode, day});
+      }
+    }
+
+    // Test too large day values.
+    for (let day = daysInMonth + 1; day <= daysInMonth + 4; ++day) {
+      let fromOrdinalMonth = Temporal.PlainDate.from({calendar, year, month, day}, {overflow: "constrain"});
+      assertDate(fromOrdinalMonth, {year, month, monthCode, day: daysInMonth});
+
+      let fromMonthCode = Temporal.PlainDate.from({calendar, year, monthCode, day}, {overflow: "constrain"});
+      assertDate(fromMonthCode, {year, month, monthCode, day: daysInMonth});
+
+      assertThrowsInstanceOf(() => {
+        Temporal.PlainDate.from({calendar, year, month, day}, {overflow: "reject"});
+      }, RangeError);
+      assertThrowsInstanceOf(() => {
+        Temporal.PlainDate.from({calendar, year, monthCode, day}, {overflow: "reject"});
+      }, RangeError);
+    }
+  }
+}
+
+if (typeof reportCompare === "function")
+  reportCompare(true, true);