Revision control
Copy as Markdown
Other Tools
use std::iter::Peekable;
use num_conv::Truncate;
use proc_macro::{token_stream, TokenTree};
use time_core::util::{days_in_year, weeks_in_year};
use crate::helpers::{
consume_any_ident, consume_number, consume_punct, days_in_year_month, ymd_to_yo, ywd_to_yo,
};
use crate::to_tokens::ToTokenTree;
use crate::Error;
#[cfg(feature = "large-dates")]
const MAX_YEAR: i32 = 999_999;
#[cfg(not(feature = "large-dates"))]
const MAX_YEAR: i32 = 9_999;
pub(crate) struct Date {
pub(crate) year: i32,
pub(crate) ordinal: u16,
}
pub(crate) fn parse(chars: &mut Peekable<token_stream::IntoIter>) -> Result<Date, Error> {
let (year_sign_span, year_sign, explicit_sign) = if let Ok(span) = consume_punct('-', chars) {
(Some(span), -1, true)
} else if let Ok(span) = consume_punct('+', chars) {
(Some(span), 1, true)
} else {
(None, 1, false)
};
let (year_span, mut year) = consume_number::<i32>("year", chars)?;
year *= year_sign;
if year.abs() > MAX_YEAR {
return Err(Error::InvalidComponent {
name: "year",
value: year.to_string(),
span_start: Some(year_sign_span.unwrap_or(year_span)),
span_end: Some(year_span),
});
}
if !explicit_sign && year.abs() >= 10_000 {
return Err(Error::Custom {
message: "years with more than four digits must have an explicit sign".into(),
span_start: Some(year_sign_span.unwrap_or(year_span)),
span_end: Some(year_span),
});
}
consume_punct('-', chars)?;
// year-week-day
if let Ok(w_span) = consume_any_ident(&["W"], chars) {
let (week_span, week) = consume_number::<u8>("week", chars)?;
consume_punct('-', chars)?;
let (day_span, day) = consume_number::<u8>("day", chars)?;
if week > weeks_in_year(year) {
return Err(Error::InvalidComponent {
name: "week",
value: week.to_string(),
span_start: Some(w_span),
span_end: Some(week_span),
});
}
if day == 0 || day > 7 {
return Err(Error::InvalidComponent {
name: "day",
value: day.to_string(),
span_start: Some(day_span),
span_end: Some(day_span),
});
}
let (year, ordinal) = ywd_to_yo(year, week, day);
return Ok(Date { year, ordinal });
}
// We don't yet know whether it's year-month-day or year-ordinal.
let (month_or_ordinal_span, month_or_ordinal) =
consume_number::<u16>("month or ordinal", chars)?;
// year-month-day
#[allow(clippy::branches_sharing_code)] // clarity
if consume_punct('-', chars).is_ok() {
let (month_span, month) = (month_or_ordinal_span, month_or_ordinal);
let (day_span, day) = consume_number::<u8>("day", chars)?;
if month == 0 || month > 12 {
return Err(Error::InvalidComponent {
name: "month",
value: month.to_string(),
span_start: Some(month_span),
span_end: Some(month_span),
});
}
let month = month.truncate();
if day == 0 || day > days_in_year_month(year, month) {
return Err(Error::InvalidComponent {
name: "day",
value: day.to_string(),
span_start: Some(day_span),
span_end: Some(day_span),
});
}
let (year, ordinal) = ymd_to_yo(year, month, day);
Ok(Date { year, ordinal })
}
// year-ordinal
else {
let (ordinal_span, ordinal) = (month_or_ordinal_span, month_or_ordinal);
if ordinal == 0 || ordinal > days_in_year(year) {
return Err(Error::InvalidComponent {
name: "ordinal",
value: ordinal.to_string(),
span_start: Some(ordinal_span),
span_end: Some(ordinal_span),
});
}
Ok(Date { year, ordinal })
}
}
impl ToTokenTree for Date {
fn into_token_tree(self) -> TokenTree {
quote_group! {{
const DATE: ::time::Date = unsafe {
::time::Date::__from_ordinal_date_unchecked(
#(self.year),
#(self.ordinal),
)
};
DATE
}}
}
}