tor-browser

commit 03bce8a97e74fba96fa316f460c23e087ea192a0
parent cb03592107ea8ccf52ece21f3bc14f5ebf0dd492
Author: André Bargull <andre.bargull@gmail.com>
Date:   Tue, 25 Nov 2025 15:19:41 +0000

Bug 2000225 - Part 18: Change extended-year for ICU4XChineseBasedCalendar to related ISO year. r=platform-i18n-reviewers,dminor

ICU 78 changed the extended year of Chinese/Dangi calendars to the related
Gregorian year. Apply the same changes for `ICU4XChineseBasedCalendar` for
consistency.

This also makes it easier to update ICU4X (bug 1997048).

Differential Revision: https://phabricator.services.mozilla.com/D273827

Diffstat:
M
intl/components/src/calendar/ICU4XChineseBasedCalendar.cpp
 | 
28
++++++++++++----------------
M
intl/components/src/calendar/ICU4XChineseBasedCalendar.h
 | 
9
---------
M
intl/components/src/calendar/ICU4XChineseCalendar.h
 | 
4
----
M
intl/components/src/calendar/ICU4XDangiCalendar.h
 | 
6
------

4 files changed, 12 insertions(+), 35 deletions(-)
diff --git a/intl/components/src/calendar/ICU4XChineseBasedCalendar.cpp b/intl/components/src/calendar/ICU4XChineseBasedCalendar.cpp
@@ -61,18 +61,6 @@ bool ICU4XChineseBasedCalendar::inTemporalLeapYear(UErrorCode& status) const {
   return days > (monthsInNonLeapYear * maxDaysInMonth);
 }
 
-int32_t ICU4XChineseBasedCalendar::getRelatedYear(UErrorCode& status) const {
-  int32_t year = get(UCAL_EXTENDED_YEAR, status);
-  if (U_FAILURE(status)) {
-    return 0;
-  }
-  return year + relatedYearDifference();
-}
-
-void ICU4XChineseBasedCalendar::setRelatedYear(int32_t year) {
-  set(UCAL_EXTENDED_YEAR, year - relatedYearDifference());
-}
-
 void ICU4XChineseBasedCalendar::handleComputeFields(int32_t julianDay,
                                                     UErrorCode& status) {
   int32_t gyear = getGregorianYear();
@@ -96,7 +84,8 @@ void ICU4XChineseBasedCalendar::handleComputeFields(int32_t julianDay,
   MOZ_ASSERT(date);
 
   MonthCode monthCode = monthCodeFrom(date.get());
-  int32_t extendedYear = icu4x::capi::icu4x_Date_extended_year_mv1(date.get());
+  int32_t extendedYear =
+      icu4x::capi::icu4x_Date_era_year_or_related_iso_mv1(date.get());
   int32_t month = icu4x::capi::icu4x_Date_ordinal_month_mv1(date.get());
   int32_t dayOfMonth = icu4x::capi::icu4x_Date_day_of_month_mv1(date.get());
   int32_t dayOfYear = icu4x::capi::icu4x_Date_day_of_year_mv1(date.get());
@@ -105,11 +94,18 @@ void ICU4XChineseBasedCalendar::handleComputeFields(int32_t julianDay,
   MOZ_ASSERT(1 <= dayOfMonth && dayOfMonth <= 30);
   MOZ_ASSERT(1 <= dayOfYear && dayOfYear <= (13 * 30));
 
+  // Difference between the Chinese calendar era (the extended year 1) and the
+  // start year used for cycle computations. This is the sixtieth year of reign
+  // of Huáng Dì. Other sources use the first year of reign, which means using
+  // -2697 instead. Both numbers result in the same year of cycle, but the
+  // latter number gives a different cycle number. To align with the ICU4C
+  // Chinese calendar implementation, we use -2637 here.
+  constexpr int32_t chineseCalendarYearDiff = -2637;
+
   // Compute the cycle and year of cycle relative to the Chinese calendar, even
   // when this is the Dangi calendar.
-  int32_t chineseExtendedYear =
-      extendedYear + relatedYearDifference() - chineseRelatedYearDiff;
-  int32_t cycle_year = chineseExtendedYear - 1;
+  int32_t chineseCalendarYear = extendedYear - chineseCalendarYearDiff;
+  int32_t cycle_year = chineseCalendarYear - 1;
   int32_t cycle = FloorDiv(cycle_year, 60);
   int32_t yearOfCycle = cycle_year - (cycle * 60);
 
diff --git a/intl/components/src/calendar/ICU4XChineseBasedCalendar.h b/intl/components/src/calendar/ICU4XChineseBasedCalendar.h
@@ -35,17 +35,8 @@ class ICU4XChineseBasedCalendar : public ICU4XCalendar {
   bool requiresFallbackForExtendedYear(int32_t year) const override;
   bool requiresFallbackForGregorianYear(int32_t year) const override;
 
-  /**
-   * Difference to the related Gregorian year.
-   */
-  virtual int32_t relatedYearDifference() const = 0;
-
-  static constexpr int32_t chineseRelatedYearDiff = -2637;
-
  public:
   bool inTemporalLeapYear(UErrorCode& status) const override;
-  int32_t getRelatedYear(UErrorCode& status) const override;
-  void setRelatedYear(int32_t year) override;
 
  protected:
   void handleComputeFields(int32_t julianDay, UErrorCode& status) override;
diff --git a/intl/components/src/calendar/ICU4XChineseCalendar.h b/intl/components/src/calendar/ICU4XChineseCalendar.h
@@ -36,10 +36,6 @@ class ICU4XChineseCalendar : public ICU4XChineseBasedCalendar {
  protected:
   std::string_view eraName(int32_t extendedYear) const override;
 
-  int32_t relatedYearDifference() const override {
-    return chineseRelatedYearDiff;
-  }
-
  public:
   UClassID getDynamicClassID() const override;
   static UClassID U_EXPORT2 getStaticClassID();
diff --git a/intl/components/src/calendar/ICU4XDangiCalendar.h b/intl/components/src/calendar/ICU4XDangiCalendar.h
@@ -36,12 +36,6 @@ class ICU4XDangiCalendar : public ICU4XChineseBasedCalendar {
  protected:
   std::string_view eraName(int32_t extendedYear) const override;
 
-  static constexpr int32_t dangiRelatedYearDiff = -2333;
-
-  int32_t relatedYearDifference() const override {
-    return dangiRelatedYearDiff;
-  }
-
  public:
   UClassID getDynamicClassID() const override;
   static UClassID U_EXPORT2 getStaticClassID();