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// This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
//! This module contains types and implementations for the Japanese calendar.
//!
//! ```rust
//! use icu::calendar::japanese::Japanese;
//! use icu::calendar::{types::Era, Date, DateTime};
//! use tinystr::tinystr;
//!
//! let japanese_calendar = Japanese::new();
//!
//! // `Date` type
//! let date_iso = Date::try_new_iso_date(1970, 1, 2)
//! .expect("Failed to initialize ISO Date instance.");
//! let date_japanese = Date::new_from_iso(date_iso, japanese_calendar.clone());
//!
//! // `DateTime` type
//! let datetime_iso = DateTime::try_new_iso_datetime(1970, 1, 2, 13, 1, 0)
//! .expect("Failed to initialize ISO DateTime instance.");
//! let datetime_japanese =
//! DateTime::new_from_iso(datetime_iso, japanese_calendar.clone());
//!
//! // `Date` checks
//! assert_eq!(date_japanese.year().number, 45);
//! assert_eq!(date_japanese.month().ordinal, 1);
//! assert_eq!(date_japanese.day_of_month().0, 2);
//! assert_eq!(date_japanese.year().era, Era(tinystr!(16, "showa")));
//!
//! // `DateTime` type
//! assert_eq!(datetime_japanese.date.year().number, 45);
//! assert_eq!(datetime_japanese.date.month().ordinal, 1);
//! assert_eq!(datetime_japanese.date.day_of_month().0, 2);
//! assert_eq!(
//! datetime_japanese.date.year().era,
//! Era(tinystr!(16, "showa"))
//! );
//! assert_eq!(datetime_japanese.time.hour.number(), 13);
//! assert_eq!(datetime_japanese.time.minute.number(), 1);
//! assert_eq!(datetime_japanese.time.second.number(), 0);
//! ```
use crate::any_calendar::AnyCalendarKind;
use crate::iso::{Iso, IsoDateInner};
use crate::provider::{EraStartDate, JapaneseErasV1Marker, JapaneseExtendedErasV1Marker};
use crate::{
types, AsCalendar, Calendar, CalendarError, Date, DateDuration, DateDurationUnit, DateTime,
Ref, Time,
};
use icu_provider::prelude::*;
use tinystr::{tinystr, TinyStr16};
/// The [Japanese Calendar] (with modern eras only)
///
/// The [Japanese calendar] is a solar calendar used in Japan, with twelve months.
/// The months and days are identical to that of the Gregorian calendar, however the years are counted
/// differently using the Japanese era system.
///
/// This calendar only contains eras after Meiji, for all historical eras, check out [`JapaneseExtended`].
///
/// This type can be used with [`Date`] or [`DateTime`] to represent dates in this calendar.
///
///
/// # Era codes
///
/// This calendar currently supports seven era codes. It supports the five post-Meiji eras
/// (`"meiji"`, `"taisho"`, `"showa"`, `"heisei"`, `"reiwa"`), as well as using the Gregorian
/// `"bce"` and `"ce"` for dates before the Meiji era.
///
/// Future eras will also be added to this type when they are decided.
///
/// These eras are loaded from data, requiring a data provider capable of providing [`JapaneseErasV1Marker`]
/// data (`calendar/japanese@1`).
///
/// # Month codes
///
/// This calendar supports 12 solar month codes (`"M01" - "M12"`)
#[derive(Clone, Debug, Default)]
pub struct Japanese {
eras: DataPayload<JapaneseErasV1Marker>,
}
/// The [Japanese Calendar] (with historical eras)
///
/// The [Japanese calendar] is a solar calendar used in Japan, with twelve months.
/// The months and days are identical to that of the Gregorian calendar, however the years are counted
/// differently using the Japanese era system.
///
/// This type can be used with [`Date`] or [`DateTime`] to represent dates in this calendar.
///
///
/// # Era codes
///
/// This calendar supports a large number of era codes. It supports the five post-Meiji eras
/// (`"meiji"`, `"taisho"`, `"showa"`, `"heisei"`, `"reiwa"`). Pre-Meiji eras are represented
/// with their names converted to lowercase ascii and followed by their start year. E.g. the "Ten'ō"
/// era (781 - 782 CE) has the code `"teno-781"`. The Gregorian `"bce"` and `"ce"` eras
/// are used for dates before the first known era era.
///
///
/// These eras are loaded from data, requiring a data provider capable of providing [`JapaneseExtendedErasV1Marker`]
/// data (`calendar/japanext@1`).
#[derive(Clone, Debug, Default)]
pub struct JapaneseExtended(Japanese);
#[derive(Copy, Clone, Debug, Hash, Eq, PartialEq, PartialOrd, Ord)]
/// The inner date type used for representing [`Date`]s of [`Japanese`]. See [`Date`] and [`Japanese`] for more details.
pub struct JapaneseDateInner {
inner: IsoDateInner,
adjusted_year: i32,
era: TinyStr16,
}
impl Japanese {
/// Creates a new [`Japanese`] using only modern eras (post-meiji) from compiled data.
///
/// ✨ *Enabled with the `compiled_data` Cargo feature.*
///
/// [📚 Help choosing a constructor](icu_provider::constructors)
#[cfg(feature = "compiled_data")]
pub const fn new() -> Self {
Self {
eras: DataPayload::from_static_ref(
crate::provider::Baked::SINGLETON_CALENDAR_JAPANESE_V1,
),
}
}
icu_provider::gen_any_buffer_data_constructors!(locale: skip, options: skip, error: CalendarError,
#[cfg(skip)]
functions: [
new,
try_new_with_any_provider,
try_new_with_buffer_provider,
try_new_unstable,
Self,
]);
#[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::new)]
pub fn try_new_unstable<D: DataProvider<JapaneseErasV1Marker> + ?Sized>(
provider: &D,
) -> Result<Self, CalendarError> {
Ok(Self {
eras: provider.load(Default::default())?.take_payload()?,
})
}
fn japanese_date_from_codes(
&self,
era: types::Era,
year: i32,
month_code: types::MonthCode,
day: u8,
debug_name: &'static str,
) -> Result<JapaneseDateInner, CalendarError> {
let month = month_code.parsed();
let month = if let Some((month, false)) = month {
month
} else {
return Err(CalendarError::UnknownMonthCode(month_code.0, debug_name));
};
if month > 12 {
return Err(CalendarError::UnknownMonthCode(month_code.0, debug_name));
}
self.new_japanese_date_inner(era, year, month, day)
}
pub(crate) const DEBUG_NAME: &'static str = "Japanese";
}
impl JapaneseExtended {
/// Creates a new [`Japanese`] from using all eras (including pre-meiji) from compiled data.
///
/// ✨ *Enabled with the `compiled_data` Cargo feature.*
///
/// [📚 Help choosing a constructor](icu_provider::constructors)
#[cfg(feature = "compiled_data")]
pub const fn new() -> Self {
Self(Japanese {
eras: DataPayload::from_static_ref(
crate::provider::Baked::SINGLETON_CALENDAR_JAPANEXT_V1,
),
})
}
icu_provider::gen_any_buffer_data_constructors!(locale: skip, options: skip, error: CalendarError,
#[cfg(skip)]
functions: [
new,
try_new_with_any_provider,
try_new_with_buffer_provider,
try_new_unstable,
Self,
]);
#[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::new)]
pub fn try_new_unstable<D: DataProvider<JapaneseExtendedErasV1Marker> + ?Sized>(
provider: &D,
) -> Result<Self, CalendarError> {
Ok(Self(Japanese {
eras: provider.load(Default::default())?.take_payload()?.cast(),
}))
}
pub(crate) const DEBUG_NAME: &'static str = "Japanese (historical era data)";
}
impl Calendar for Japanese {
type DateInner = JapaneseDateInner;
fn date_from_codes(
&self,
era: types::Era,
year: i32,
month_code: types::MonthCode,
day: u8,
) -> Result<Self::DateInner, CalendarError> {
self.japanese_date_from_codes(era, year, month_code, day, self.debug_name())
}
fn date_from_iso(&self, iso: Date<Iso>) -> JapaneseDateInner {
let (adjusted_year, era) = self.adjusted_year_for(iso.inner());
JapaneseDateInner {
inner: *iso.inner(),
adjusted_year,
era,
}
}
fn date_to_iso(&self, date: &Self::DateInner) -> Date<Iso> {
Date::from_raw(date.inner, Iso)
}
fn months_in_year(&self, date: &Self::DateInner) -> u8 {
Iso.months_in_year(&date.inner)
}
fn days_in_year(&self, date: &Self::DateInner) -> u16 {
Iso.days_in_year(&date.inner)
}
fn days_in_month(&self, date: &Self::DateInner) -> u8 {
Iso.days_in_month(&date.inner)
}
fn offset_date(&self, date: &mut Self::DateInner, offset: DateDuration<Self>) {
Iso.offset_date(&mut date.inner, offset.cast_unit());
let (adjusted_year, era) = self.adjusted_year_for(&date.inner);
date.adjusted_year = adjusted_year;
date.era = era
}
fn until(
&self,
date1: &Self::DateInner,
date2: &Self::DateInner,
_calendar2: &Self,
largest_unit: DateDurationUnit,
smallest_unit: DateDurationUnit,
) -> DateDuration<Self> {
Iso.until(
&date1.inner,
&date2.inner,
&Iso,
largest_unit,
smallest_unit,
)
.cast_unit()
}
/// The calendar-specific year represented by `date`
fn year(&self, date: &Self::DateInner) -> types::FormattableYear {
types::FormattableYear {
era: types::Era(date.era),
number: date.adjusted_year,
cyclic: None,
related_iso: None,
}
}
fn is_in_leap_year(&self, date: &Self::DateInner) -> bool {
Iso.is_in_leap_year(&date.inner)
}
/// The calendar-specific month represented by `date`
fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
Iso.month(&date.inner)
}
/// The calendar-specific day-of-month represented by `date`
fn day_of_month(&self, date: &Self::DateInner) -> types::DayOfMonth {
Iso.day_of_month(&date.inner)
}
/// Information of the day of the year
fn day_of_year_info(&self, date: &Self::DateInner) -> types::DayOfYearInfo {
let prev_dec_31 = IsoDateInner::dec_31(date.inner.0.year - 1);
let next_jan_1 = IsoDateInner::jan_1(date.inner.0.year + 1);
let prev_dec_31 = self.date_from_iso(Date::from_raw(prev_dec_31, Iso));
let next_jan_1 = self.date_from_iso(Date::from_raw(next_jan_1, Iso));
types::DayOfYearInfo {
day_of_year: Iso::days_in_year_direct(date.inner.0.year),
days_in_year: Iso::days_in_year_direct(date.inner.0.year),
prev_year: self.year(&prev_dec_31),
days_in_prev_year: Iso::days_in_year_direct(prev_dec_31.inner.0.year),
next_year: self.year(&next_jan_1),
}
}
fn debug_name(&self) -> &'static str {
Self::DEBUG_NAME
}
fn any_calendar_kind(&self) -> Option<AnyCalendarKind> {
Some(AnyCalendarKind::Japanese)
}
}
impl Calendar for JapaneseExtended {
type DateInner = JapaneseDateInner;
fn date_from_codes(
&self,
era: types::Era,
year: i32,
month_code: types::MonthCode,
day: u8,
) -> Result<Self::DateInner, CalendarError> {
self.0
.japanese_date_from_codes(era, year, month_code, day, self.debug_name())
}
fn date_from_iso(&self, iso: Date<Iso>) -> JapaneseDateInner {
Japanese::date_from_iso(&self.0, iso)
}
fn date_to_iso(&self, date: &Self::DateInner) -> Date<Iso> {
Japanese::date_to_iso(&self.0, date)
}
fn months_in_year(&self, date: &Self::DateInner) -> u8 {
Japanese::months_in_year(&self.0, date)
}
fn days_in_year(&self, date: &Self::DateInner) -> u16 {
Japanese::days_in_year(&self.0, date)
}
fn days_in_month(&self, date: &Self::DateInner) -> u8 {
Japanese::days_in_month(&self.0, date)
}
fn offset_date(&self, date: &mut Self::DateInner, offset: DateDuration<Self>) {
Japanese::offset_date(&self.0, date, offset.cast_unit())
}
fn until(
&self,
date1: &Self::DateInner,
date2: &Self::DateInner,
calendar2: &Self,
largest_unit: DateDurationUnit,
smallest_unit: DateDurationUnit,
) -> DateDuration<Self> {
Japanese::until(
&self.0,
date1,
date2,
&calendar2.0,
largest_unit,
smallest_unit,
)
.cast_unit()
}
/// The calendar-specific year represented by `date`
fn year(&self, date: &Self::DateInner) -> types::FormattableYear {
Japanese::year(&self.0, date)
}
fn is_in_leap_year(&self, date: &Self::DateInner) -> bool {
Japanese::is_in_leap_year(&self.0, date)
}
/// The calendar-specific month represented by `date`
fn month(&self, date: &Self::DateInner) -> types::FormattableMonth {
Japanese::month(&self.0, date)
}
/// The calendar-specific day-of-month represented by `date`
fn day_of_month(&self, date: &Self::DateInner) -> types::DayOfMonth {
Japanese::day_of_month(&self.0, date)
}
/// Information of the day of the year
fn day_of_year_info(&self, date: &Self::DateInner) -> types::DayOfYearInfo {
Japanese::day_of_year_info(&self.0, date)
}
fn debug_name(&self) -> &'static str {
Self::DEBUG_NAME
}
fn any_calendar_kind(&self) -> Option<AnyCalendarKind> {
Some(AnyCalendarKind::JapaneseExtended)
}
}
impl Date<Japanese> {
/// Construct a new Japanese Date.
///
/// Years are specified in the era provided, and must be in range for Japanese
/// eras (e.g. dates past April 30 Heisei 31 must be in Reiwa; "Jun 5 Heisei 31" and "Jan 1 Heisei 32"
/// will not be adjusted to being in Reiwa 1 and 2 respectively)
///
/// However, dates may always be specified in "bce" or "ce" and they will be adjusted as necessary.
///
/// ```rust
/// use icu::calendar::japanese::Japanese;
/// use icu::calendar::{types, Date, Ref};
/// use tinystr::tinystr;
///
/// let japanese_calendar = Japanese::new();
/// // for easy sharing
/// let japanese_calendar = Ref(&japanese_calendar);
///
/// let era = types::Era(tinystr!(16, "heisei"));
///
/// let date = Date::try_new_japanese_date(era, 14, 1, 2, japanese_calendar)
/// .expect("Constructing a date should succeed");
///
/// assert_eq!(date.year().era, era);
/// assert_eq!(date.year().number, 14);
/// assert_eq!(date.month().ordinal, 1);
/// assert_eq!(date.day_of_month().0, 2);
///
/// // This function will error for eras that are out of bounds:
/// // (Heisei was 32 years long, Heisei 33 is in Reiwa)
/// let oob_date =
/// Date::try_new_japanese_date(era, 33, 1, 2, japanese_calendar);
/// assert!(oob_date.is_err());
///
/// // and for unknown eras
/// let fake_era = types::Era(tinystr!(16, "neko")); // 🐱
/// let fake_date =
/// Date::try_new_japanese_date(fake_era, 10, 1, 2, japanese_calendar);
/// assert!(fake_date.is_err());
/// ```
pub fn try_new_japanese_date<A: AsCalendar<Calendar = Japanese>>(
era: types::Era,
year: i32,
month: u8,
day: u8,
japanese_calendar: A,
) -> Result<Date<A>, CalendarError> {
let inner = japanese_calendar
.as_calendar()
.new_japanese_date_inner(era, year, month, day)?;
Ok(Date::from_raw(inner, japanese_calendar))
}
}
impl Date<JapaneseExtended> {
/// Construct a new Japanese Date with all eras.
///
/// Years are specified in the era provided, and must be in range for Japanese
/// eras (e.g. dates past April 30 Heisei 31 must be in Reiwa; "Jun 5 Heisei 31" and "Jan 1 Heisei 32"
/// will not be adjusted to being in Reiwa 1 and 2 respectively)
///
/// However, dates may always be specified in "bce" or "ce" and they will be adjusted as necessary.
///
/// ```rust
/// use icu::calendar::japanese::JapaneseExtended;
/// use icu::calendar::{types, Date, Ref};
/// use tinystr::tinystr;
///
/// let japanext_calendar = JapaneseExtended::new();
/// // for easy sharing
/// let japanext_calendar = Ref(&japanext_calendar);
///
/// let era = types::Era(tinystr!(16, "kansei-1789"));
///
/// let date =
/// Date::try_new_japanese_extended_date(era, 7, 1, 2, japanext_calendar)
/// .expect("Constructing a date should succeed");
///
/// assert_eq!(date.year().era, era);
/// assert_eq!(date.year().number, 7);
/// assert_eq!(date.month().ordinal, 1);
/// assert_eq!(date.day_of_month().0, 2);
/// ```
pub fn try_new_japanese_extended_date<A: AsCalendar<Calendar = JapaneseExtended>>(
era: types::Era,
year: i32,
month: u8,
day: u8,
japanext_calendar: A,
) -> Result<Date<A>, CalendarError> {
let inner = japanext_calendar
.as_calendar()
.0
.new_japanese_date_inner(era, year, month, day)?;
Ok(Date::from_raw(inner, japanext_calendar))
}
// For testing era fallback in icu_datetime
#[doc(hidden)]
pub fn into_japanese_date(self) -> Date<Japanese> {
Date::from_raw(self.inner, self.calendar.0)
}
}
impl DateTime<Japanese> {
/// Construct a new Japanese datetime from integers.
///
/// Years are specified in the era provided.
///
/// ```rust
/// use icu::calendar::japanese::Japanese;
/// use icu::calendar::{types, DateTime};
/// use tinystr::tinystr;
///
/// let japanese_calendar = Japanese::new();
///
/// let era = types::Era(tinystr!(16, "heisei"));
///
/// let datetime = DateTime::try_new_japanese_datetime(
/// era,
/// 14,
/// 1,
/// 2,
/// 13,
/// 1,
/// 0,
/// japanese_calendar,
/// )
/// .expect("Constructing a date should succeed");
///
/// assert_eq!(datetime.date.year().era, era);
/// assert_eq!(datetime.date.year().number, 14);
/// assert_eq!(datetime.date.month().ordinal, 1);
/// assert_eq!(datetime.date.day_of_month().0, 2);
/// assert_eq!(datetime.time.hour.number(), 13);
/// assert_eq!(datetime.time.minute.number(), 1);
/// assert_eq!(datetime.time.second.number(), 0);
/// ```
#[allow(clippy::too_many_arguments)] // it's more convenient to have this many arguments
// if people wish to construct this by parts they can use
// Date::try_new_japanese_date() + DateTime::new(date, time)
pub fn try_new_japanese_datetime<A: AsCalendar<Calendar = Japanese>>(
era: types::Era,
year: i32,
month: u8,
day: u8,
hour: u8,
minute: u8,
second: u8,
japanese_calendar: A,
) -> Result<DateTime<A>, CalendarError> {
Ok(DateTime {
date: Date::try_new_japanese_date(era, year, month, day, japanese_calendar)?,
time: Time::try_new(hour, minute, second, 0)?,
})
}
}
impl DateTime<JapaneseExtended> {
/// Construct a new Japanese datetime from integers with all eras.
///
/// Years are specified in the era provided.
///
/// ```rust
/// use icu::calendar::japanese::JapaneseExtended;
/// use icu::calendar::{types, DateTime};
/// use tinystr::tinystr;
///
/// let japanext_calendar = JapaneseExtended::new();
///
/// let era = types::Era(tinystr!(16, "kansei-1789"));
///
/// let datetime = DateTime::try_new_japanese_extended_datetime(
/// era,
/// 7,
/// 1,
/// 2,
/// 13,
/// 1,
/// 0,
/// japanext_calendar,
/// )
/// .expect("Constructing a date should succeed");
///
/// assert_eq!(datetime.date.year().era, era);
/// assert_eq!(datetime.date.year().number, 7);
/// assert_eq!(datetime.date.month().ordinal, 1);
/// assert_eq!(datetime.date.day_of_month().0, 2);
/// assert_eq!(datetime.time.hour.number(), 13);
/// assert_eq!(datetime.time.minute.number(), 1);
/// assert_eq!(datetime.time.second.number(), 0);
/// ```
#[allow(clippy::too_many_arguments)] // it's more convenient to have this many arguments
// if people wish to construct this by parts they can use
// Date::try_new_japanese_date() + DateTime::new(date, time)
pub fn try_new_japanese_extended_datetime<A: AsCalendar<Calendar = JapaneseExtended>>(
era: types::Era,
year: i32,
month: u8,
day: u8,
hour: u8,
minute: u8,
second: u8,
japanext_calendar: A,
) -> Result<DateTime<A>, CalendarError> {
Ok(DateTime {
date: Date::try_new_japanese_extended_date(era, year, month, day, japanext_calendar)?,
time: Time::try_new(hour, minute, second, 0)?,
})
}
}
const MEIJI_START: EraStartDate = EraStartDate {
year: 1868,
month: 9,
day: 8,
};
const TAISHO_START: EraStartDate = EraStartDate {
year: 1912,
month: 7,
day: 30,
};
const SHOWA_START: EraStartDate = EraStartDate {
year: 1926,
month: 12,
day: 25,
};
const HEISEI_START: EraStartDate = EraStartDate {
year: 1989,
month: 1,
day: 8,
};
const REIWA_START: EraStartDate = EraStartDate {
year: 2019,
month: 5,
day: 1,
};
const FALLBACK_ERA: (EraStartDate, TinyStr16) = (REIWA_START, tinystr!(16, "reiwa"));
impl Japanese {
/// Given an ISO date, give year and era for that date in the Japanese calendar
///
/// This will also use Gregorian eras for eras that are before the earliest era
fn adjusted_year_for(&self, date: &IsoDateInner) -> (i32, TinyStr16) {
let date: EraStartDate = date.into();
let (start, era) = self.japanese_era_for(date);
// The year in which an era starts is Year 1, and it may be short
// The only time this function will experience dates that are *before*
// the era start date are for the first era (Currently, taika-645
// for japanext, meiji for japanese),
// In such a case, we instead fall back to Gregorian era codes
if date < start {
if date.year <= 0 {
(1 - date.year, tinystr!(16, "bce"))
} else {
(date.year, tinystr!(16, "ce"))
}
} else {
(date.year - start.year + 1, era)
}
}
/// Given an date, obtain the era data (not counting spliced gregorian eras)
fn japanese_era_for(&self, date: EraStartDate) -> (EraStartDate, TinyStr16) {
let era_data = self.eras.get();
// We optimize for the five "modern" post-Meiji eras, which are stored in a smaller
// array and also hardcoded. The hardcoded version is not used if data indicates the
// presence of newer eras.
if date >= MEIJI_START
&& era_data.dates_to_eras.last().map(|x| x.1) == Some(tinystr!(16, "reiwa"))
{
// Fast path in case eras have not changed since this code was written
return if date >= REIWA_START {
(REIWA_START, tinystr!(16, "reiwa"))
} else if date >= HEISEI_START {
(HEISEI_START, tinystr!(16, "heisei"))
} else if date >= SHOWA_START {
(SHOWA_START, tinystr!(16, "showa"))
} else if date >= TAISHO_START {
(TAISHO_START, tinystr!(16, "taisho"))
} else {
(MEIJI_START, tinystr!(16, "meiji"))
};
}
let data = &era_data.dates_to_eras;
match data.binary_search_by(|(d, _)| d.cmp(&date)) {
Ok(index) => data.get(index),
Err(index) if index == 0 => data.get(index),
Err(index) => data.get(index - 1).or_else(|| data.iter().next_back()),
}
.unwrap_or(FALLBACK_ERA)
}
/// Returns the range of dates for a given Japanese era code,
/// not handling "bce" or "ce"
///
/// Returns (era_start, era_end)
fn japanese_era_range_for(
&self,
era: TinyStr16,
) -> Result<(EraStartDate, Option<EraStartDate>), CalendarError> {
// Avoid linear search by trying well known eras
if era == tinystr!(16, "reiwa") {
// Check if we're the last
if let Some(last) = self.eras.get().dates_to_eras.last() {
if last.1 == era {
return Ok((REIWA_START, None));
}
}
} else if era == tinystr!(16, "heisei") {
return Ok((HEISEI_START, Some(REIWA_START)));
} else if era == tinystr!(16, "showa") {
return Ok((SHOWA_START, Some(HEISEI_START)));
} else if era == tinystr!(16, "taisho") {
return Ok((TAISHO_START, Some(SHOWA_START)));
} else if era == tinystr!(16, "meiji") {
return Ok((MEIJI_START, Some(TAISHO_START)));
}
let era_data = self.eras.get();
let data = &era_data.dates_to_eras;
// Try to avoid linear search by binary searching for the year suffix
if let Some(year) = era.split('-').nth(1) {
if let Ok(ref int) = year.parse::<i32>() {
if let Ok(index) = data.binary_search_by(|(d, _)| d.year.cmp(int)) {
#[allow(clippy::expect_used)] // see expect message
let (era_start, code) = data
.get(index)
.expect("Indexing from successful binary search must succeed");
// There is a slight chance we hit the case where there are two eras in the same year
// There are a couple of rare cases of this, but it's not worth writing a range-based binary search
// to catch them since this is an optimization
if code == era {
return Ok((era_start, data.get(index + 1).map(|e| e.0)));
}
}
}
}
// Avoidance didn't work. Let's find the era manually, searching back from the present
if let Some((index, (start, _))) = data.iter().enumerate().rev().find(|d| d.1 .1 == era) {
return Ok((start, data.get(index + 1).map(|e| e.0)));
}
Err(CalendarError::UnknownEra(era, self.debug_name()))
}
fn new_japanese_date_inner(
&self,
era: types::Era,
year: i32,
month: u8,
day: u8,
) -> Result<JapaneseDateInner, CalendarError> {
let cal = Ref(self);
if era.0 == tinystr!(16, "bce") {
if year <= 0 {
return Err(CalendarError::OutOfRange);
}
return Ok(Date::try_new_iso_date(1 - year, month, day)?
.to_calendar(cal)
.inner);
} else if era.0 == tinystr!(16, "ce") {
if year <= 0 {
return Err(CalendarError::OutOfRange);
}
return Ok(Date::try_new_iso_date(year, month, day)?
.to_calendar(cal)
.inner);
}
let (era_start, next_era_start) = self.japanese_era_range_for(era.0)?;
let date_in_iso = EraStartDate {
year: era_start.year + year - 1,
month,
day,
};
if date_in_iso < era_start {
return Err(CalendarError::OutOfRange);
} else if let Some(next_era_start) = next_era_start {
if date_in_iso >= next_era_start {
return Err(CalendarError::OutOfRange);
}
}
let iso = Date::try_new_iso_date(date_in_iso.year, date_in_iso.month, date_in_iso.day)?;
Ok(JapaneseDateInner {
inner: iso.inner,
adjusted_year: year,
era: era.0,
})
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::Ref;
fn single_test_roundtrip(calendar: Ref<Japanese>, era: &str, year: i32, month: u8, day: u8) {
let era = types::Era(era.parse().expect("era must parse"));
let date =
Date::try_new_japanese_date(era, year, month, day, calendar).unwrap_or_else(|e| {
panic!("Failed to construct date with {era:?}, {year}, {month}, {day}: {e}")
});
let iso = date.to_iso();
let reconstructed = Date::new_from_iso(iso, calendar);
assert_eq!(
date, reconstructed,
"Failed to roundtrip with {era:?}, {year}, {month}, {day}"
);
assert_eq!(reconstructed.year().era, era);
assert_eq!(reconstructed.year().number, year);
}
fn single_test_roundtrip_ext(
calendar: Ref<JapaneseExtended>,
era: &str,
year: i32,
month: u8,
day: u8,
) {
let era = types::Era(era.parse().expect("era must parse"));
let date = Date::try_new_japanese_extended_date(era, year, month, day, calendar)
.unwrap_or_else(|e| {
panic!("Failed to construct date with {era:?}, {year}, {month}, {day}: {e}")
});
let iso = date.to_iso();
let reconstructed = Date::new_from_iso(iso, calendar);
assert_eq!(
date, reconstructed,
"Failed to roundtrip with {era:?}, {year}, {month}, {day}"
)
}
// test that the Gregorian eras roundtrip to Japanese ones
fn single_test_gregorian_roundtrip_ext(
calendar: Ref<JapaneseExtended>,
era: &str,
year: i32,
month: u8,
day: u8,
era2: &str,
year2: i32,
) {
let era = types::Era(era.parse().expect("era must parse"));
let era2 = types::Era(era2.parse().expect("era must parse"));
let expected = Date::try_new_japanese_extended_date(era2, year2, month, day, calendar)
.unwrap_or_else(|e| {
panic!(
"Failed to construct expectation date with {era2:?}, {year2}, {month}, {day}: {e}"
)
});
let date = Date::try_new_japanese_extended_date(era, year, month, day, calendar)
.unwrap_or_else(|e| {
panic!("Failed to construct date with {era:?}, {year}, {month}, {day}: {e}")
});
let iso = date.to_iso();
let reconstructed = Date::new_from_iso(iso, calendar);
assert_eq!(
expected, reconstructed,
"Failed to roundtrip with {era:?}, {year}, {month}, {day} == {era2:?}, {year}"
)
}
fn single_test_error(
calendar: Ref<Japanese>,
era: &str,
year: i32,
month: u8,
day: u8,
error: CalendarError,
) {
let era = types::Era(era.parse().expect("era must parse"));
let date = Date::try_new_japanese_date(era, year, month, day, calendar);
assert_eq!(
date,
Err(error),
"Construction with {era:?}, {year}, {month}, {day} did not return {error:?}"
)
}
fn single_test_error_ext(
calendar: Ref<JapaneseExtended>,
era: &str,
year: i32,
month: u8,
day: u8,
error: CalendarError,
) {
let era = types::Era(era.parse().expect("era must parse"));
let date = Date::try_new_japanese_extended_date(era, year, month, day, calendar);
assert_eq!(
date,
Err(error),
"Construction with {era:?}, {year}, {month}, {day} did not return {error:?}"
)
}
#[test]
fn test_japanese() {
let calendar = Japanese::new();
let calendar_ext = JapaneseExtended::new();
let calendar = Ref(&calendar);
let calendar_ext = Ref(&calendar_ext);
single_test_roundtrip(calendar, "heisei", 12, 3, 1);
single_test_roundtrip(calendar, "taisho", 3, 3, 1);
// Heisei did not start until later in the year
single_test_error(calendar, "heisei", 1, 1, 1, CalendarError::OutOfRange);
single_test_roundtrip_ext(calendar_ext, "heisei", 12, 3, 1);
single_test_roundtrip_ext(calendar_ext, "taisho", 3, 3, 1);
single_test_error_ext(calendar_ext, "heisei", 1, 1, 1, CalendarError::OutOfRange);
single_test_roundtrip_ext(calendar_ext, "hakuho-672", 4, 3, 1);
single_test_error(
calendar,
"hakuho-672",
4,
3,
1,
CalendarError::UnknownEra("hakuho-672".parse().unwrap(), "Japanese"),
);
// handle bce/ce
single_test_roundtrip(calendar, "bce", 100, 3, 1);
single_test_roundtrip(calendar, "bce", 1, 3, 1);
single_test_roundtrip(calendar, "ce", 1, 3, 1);
single_test_roundtrip(calendar, "ce", 100, 3, 1);
single_test_roundtrip_ext(calendar_ext, "ce", 100, 3, 1);
single_test_roundtrip(calendar, "ce", 1000, 3, 1);
single_test_error(calendar, "ce", 0, 3, 1, CalendarError::OutOfRange);
single_test_error(calendar, "bce", -1, 3, 1, CalendarError::OutOfRange);
// handle the cases where bce/ce get adjusted to different eras
// single_test_gregorian_roundtrip(calendar, "ce", 2021, 3, 1, "reiwa", 3);
single_test_gregorian_roundtrip_ext(calendar_ext, "ce", 1000, 3, 1, "choho-999", 2);
single_test_gregorian_roundtrip_ext(calendar_ext, "ce", 749, 5, 10, "tenpyokampo-749", 1);
single_test_gregorian_roundtrip_ext(calendar_ext, "bce", 10, 3, 1, "bce", 10);
// There were multiple eras in this year
// This one is from Apr 14 to July 2
single_test_roundtrip_ext(calendar_ext, "tenpyokampo-749", 1, 4, 20);
single_test_roundtrip_ext(calendar_ext, "tenpyokampo-749", 1, 4, 14);
single_test_roundtrip_ext(calendar_ext, "tenpyokampo-749", 1, 7, 1);
single_test_error_ext(
calendar_ext,
"tenpyokampo-749",
1,
7,
5,
CalendarError::OutOfRange,
);
single_test_error_ext(
calendar_ext,
"tenpyokampo-749",
1,
4,
13,
CalendarError::OutOfRange,
);
}
}