unicode-org · Manishearth · Nov 13, 2023 · Nov 13, 2023 · Nov 13, 2023
@@ -515,6 +515,11 @@ impl Calendar for AnyCalendar {
         match_cal_and_date!(match (self, date): (c, d) => c.year(d))
     }
 
+    /// The calendar-specific check if year is a leap year represented by `date`
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        match_cal_and_date!(match (self, date): (c, d) => c.year_is_leap(d))
+    }
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         match_cal_and_date!(match (self, date): (c, d) => c.month(d))

@@ -122,6 +122,10 @@ impl Calendar for Buddhist {
         iso_year_as_buddhist(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Iso.year_is_leap(date)
+    }
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         Iso.month(date)

@@ -75,6 +75,9 @@ pub trait Calendar {
     /// The calendar-specific year represented by `date`
     fn year(&self, date: &Self::DateInner) -> types::FormattableYear;
 
+    /// Calculate if a date is in a leap year
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool;
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth;
 

@@ -226,6 +226,10 @@ impl Calendar for Chinese {
         Self::format_chinese_year(date.0 .0.year, Some(date.0 .1))
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0 .0.year)
+    }
+
     /// The calendar-specific month code represented by `date`;
     /// since the Chinese calendar has leap months, an "L" is appended to the month code for
     /// leap months. For example, in a year where an intercalary month is added after the second

@@ -176,6 +176,10 @@ impl Calendar for Coptic {
         year_as_coptic(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }

@@ -206,6 +206,10 @@ impl Calendar for Dangi {
         Self::format_dangi_year(date.0 .0.year, Some(date.0 .1))
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0 .0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> crate::types::FormattableMonth {
         let ordinal = date.0 .0.month;
         let leap_month_option = date.0 .1.get_leap_month();

@@ -214,6 +214,12 @@ impl<A: AsCalendar> Date<A> {
         self.calendar.as_calendar().year(&self.inner)
     }
 
+    /// The calendar-specific year represented by `self` is a leap year
+    #[inline]
+    pub fn year_is_leap(&self) -> bool {
+        self.calendar.as_calendar().year_is_leap(&self.inner)
+    }
+
     /// The calendar-specific month represented by `self`
     #[inline]
     pub fn month(&self) -> types::FormattableMonth {

@@ -198,6 +198,10 @@ impl Calendar for Ethiopian {
         Self::year_as_ethiopian(date.0.year, self.0)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }

@@ -126,6 +126,10 @@ impl Calendar for Gregorian {
         year_as_gregorian(date.0 .0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Iso.year_is_leap(&date.0)
+    }
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         Iso.month(&date.0)

@@ -228,6 +228,10 @@ impl Calendar for Hebrew {
         Self::year_as_hebrew(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> FormattableMonth {
         let mut ordinal = date.0.month;
         let is_leap_year = Self::is_leap_year(date.0.year);

@@ -200,6 +200,10 @@ impl Calendar for Indian {
         }
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }

@@ -239,6 +239,10 @@ impl Calendar for IslamicObservational {
         Self::year_as_islamic(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }
@@ -464,6 +468,10 @@ impl Calendar for IslamicUmmAlQura {
         Self::year_as_islamic(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }
@@ -704,6 +712,10 @@ impl Calendar for IslamicCivil {
         Self::year_as_islamic(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }
@@ -944,6 +956,10 @@ impl Calendar for IslamicTabular {
         Self::year_as_islamic(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }

@@ -194,6 +194,10 @@ impl Calendar for Iso {
         Self::year_as_iso(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()

@@ -282,6 +282,10 @@ impl Calendar for Japanese {
         }
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Iso.year_is_leap(&date.inner)
+    }
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         Iso.month(&date.inner)
@@ -379,6 +383,10 @@ impl Calendar for JapaneseExtended {
         Japanese::year(&self.0, date)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Japanese::year_is_leap(&self.0, date)
+    }
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         Japanese::month(&self.0, date)

@@ -169,6 +169,10 @@ impl Calendar for Julian {
         year_as_gregorian(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     /// The calendar-specific month represented by `date`
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()

@@ -171,6 +171,10 @@ impl Calendar for Persian {
         Self::year_as_persian(date.0.year)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Self::is_leap_year(date.0.year)
+    }
+
     fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
         date.0.month()
     }

@@ -146,6 +146,10 @@ impl Calendar for Roc {
         year_as_roc(date.0 .0.year as i64)
     }
 
+    fn year_is_leap(&self, date: &Self::DateInner) -> bool {
+        Iso.year_is_leap(&date.0)
+    }
+
     fn month(&self, date: &Self::DateInner) -> crate::types::FormattableMonth {
         Iso.month(&date.0)
     }