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// This is a part of Chrono.
// See README.md and LICENSE.txt for details.
//! Formatting (and parsing) utilities for date and time.
//!
//! This module provides the common types and routines to implement,
//! for example, [`DateTime::format`](../struct.DateTime.html#method.format) or
//! [`DateTime::parse_from_str`](../struct.DateTime.html#method.parse_from_str) methods.
//! For most cases you should use these high-level interfaces.
//!
//! Internally the formatting and parsing shares the same abstract **formatting items**,
//! the [`Item`](./enum.Item.html) type.
//! They are generated from more readable **format strings**;
//! currently Chrono supports [one built-in syntax closely resembling
//! C's `strftime` format](./strftime/index.html).
#![allow(ellipsis_inclusive_range_patterns)]
#[cfg(feature = "alloc")]
use alloc::boxed::Box;
#[cfg(feature = "alloc")]
use alloc::string::{String, ToString};
#[cfg(any(feature = "alloc", feature = "std", test))]
use core::borrow::Borrow;
use core::fmt;
use core::str::FromStr;
#[cfg(any(feature = "std", test))]
use std::error::Error;
#[cfg(any(feature = "alloc", feature = "std", test))]
use naive::{NaiveDate, NaiveTime};
#[cfg(any(feature = "alloc", feature = "std", test))]
use offset::{FixedOffset, Offset};
#[cfg(any(feature = "alloc", feature = "std", test))]
use {Datelike, Timelike};
use {Month, ParseMonthError, ParseWeekdayError, Weekday};
#[cfg(feature = "unstable-locales")]
pub(crate) mod locales;
pub use self::parse::parse;
pub use self::parsed::Parsed;
pub use self::strftime::StrftimeItems;
/// L10n locales.
#[cfg(feature = "unstable-locales")]
pub use pure_rust_locales::Locale;
#[cfg(not(feature = "unstable-locales"))]
#[derive(Debug)]
struct Locale;
/// An uninhabited type used for `InternalNumeric` and `InternalFixed` below.
#[derive(Clone, PartialEq, Eq)]
enum Void {}
/// Padding characters for numeric items.
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum Pad {
/// No padding.
None,
/// Zero (`0`) padding.
Zero,
/// Space padding.
Space,
}
/// Numeric item types.
/// They have associated formatting width (FW) and parsing width (PW).
///
/// The **formatting width** is the minimal width to be formatted.
/// If the number is too short, and the padding is not [`Pad::None`](./enum.Pad.html#variant.None),
/// then it is left-padded.
/// If the number is too long or (in some cases) negative, it is printed as is.
///
/// The **parsing width** is the maximal width to be scanned.
/// The parser only tries to consume from one to given number of digits (greedily).
/// It also trims the preceding whitespace if any.
/// It cannot parse the negative number, so some date and time cannot be formatted then
/// parsed with the same formatting items.
#[derive(Clone, PartialEq, Eq, Debug)]
pub enum Numeric {
/// Full Gregorian year (FW=4, PW=∞).
/// May accept years before 1 BCE or after 9999 CE, given an initial sign.
Year,
/// Gregorian year divided by 100 (century number; FW=PW=2). Implies the non-negative year.
YearDiv100,
/// Gregorian year modulo 100 (FW=PW=2). Cannot be negative.
YearMod100,
/// Year in the ISO week date (FW=4, PW=∞).
/// May accept years before 1 BCE or after 9999 CE, given an initial sign.
IsoYear,
/// Year in the ISO week date, divided by 100 (FW=PW=2). Implies the non-negative year.
IsoYearDiv100,
/// Year in the ISO week date, modulo 100 (FW=PW=2). Cannot be negative.
IsoYearMod100,
/// Month (FW=PW=2).
Month,
/// Day of the month (FW=PW=2).
Day,
/// Week number, where the week 1 starts at the first Sunday of January (FW=PW=2).
WeekFromSun,
/// Week number, where the week 1 starts at the first Monday of January (FW=PW=2).
WeekFromMon,
/// Week number in the ISO week date (FW=PW=2).
IsoWeek,
/// Day of the week, where Sunday = 0 and Saturday = 6 (FW=PW=1).
NumDaysFromSun,
/// Day of the week, where Monday = 1 and Sunday = 7 (FW=PW=1).
WeekdayFromMon,
/// Day of the year (FW=PW=3).
Ordinal,
/// Hour number in the 24-hour clocks (FW=PW=2).
Hour,
/// Hour number in the 12-hour clocks (FW=PW=2).
Hour12,
/// The number of minutes since the last whole hour (FW=PW=2).
Minute,
/// The number of seconds since the last whole minute (FW=PW=2).
Second,
/// The number of nanoseconds since the last whole second (FW=PW=9).
/// Note that this is *not* left-aligned;
/// see also [`Fixed::Nanosecond`](./enum.Fixed.html#variant.Nanosecond).
Nanosecond,
/// The number of non-leap seconds since the midnight UTC on January 1, 1970 (FW=1, PW=∞).
/// For formatting, it assumes UTC upon the absence of time zone offset.
Timestamp,
/// Internal uses only.
///
/// This item exists so that one can add additional internal-only formatting
/// without breaking major compatibility (as enum variants cannot be selectively private).
Internal(InternalNumeric),
}
/// An opaque type representing numeric item types for internal uses only.
pub struct InternalNumeric {
_dummy: Void,
}
impl Clone for InternalNumeric {
fn clone(&self) -> Self {
match self._dummy {}
}
}
impl PartialEq for InternalNumeric {
fn eq(&self, _other: &InternalNumeric) -> bool {
match self._dummy {}
}
}
impl Eq for InternalNumeric {}
impl fmt::Debug for InternalNumeric {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "<InternalNumeric>")
}
}
/// Fixed-format item types.
///
/// They have their own rules of formatting and parsing.
/// Otherwise noted, they print in the specified cases but parse case-insensitively.
#[derive(Clone, PartialEq, Eq, Debug)]
pub enum Fixed {
/// Abbreviated month names.
///
/// Prints a three-letter-long name in the title case, reads the same name in any case.
ShortMonthName,
/// Full month names.
///
/// Prints a full name in the title case, reads either a short or full name in any case.
LongMonthName,
/// Abbreviated day of the week names.
///
/// Prints a three-letter-long name in the title case, reads the same name in any case.
ShortWeekdayName,
/// Full day of the week names.
///
/// Prints a full name in the title case, reads either a short or full name in any case.
LongWeekdayName,
/// AM/PM.
///
/// Prints in lower case, reads in any case.
LowerAmPm,
/// AM/PM.
///
/// Prints in upper case, reads in any case.
UpperAmPm,
/// An optional dot plus one or more digits for left-aligned nanoseconds.
/// May print nothing, 3, 6 or 9 digits according to the available accuracy.
/// See also [`Numeric::Nanosecond`](./enum.Numeric.html#variant.Nanosecond).
Nanosecond,
/// Same as [`Nanosecond`](#variant.Nanosecond) but the accuracy is fixed to 3.
Nanosecond3,
/// Same as [`Nanosecond`](#variant.Nanosecond) but the accuracy is fixed to 6.
Nanosecond6,
/// Same as [`Nanosecond`](#variant.Nanosecond) but the accuracy is fixed to 9.
Nanosecond9,
/// Timezone name.
///
/// It does not support parsing, its use in the parser is an immediate failure.
TimezoneName,
/// Offset from the local time to UTC (`+09:00` or `-04:00` or `+00:00`).
///
/// In the parser, the colon can be omitted and/or surrounded with any amount of whitespace.
/// The offset is limited from `-24:00` to `+24:00`,
/// which is the same as [`FixedOffset`](../offset/struct.FixedOffset.html)'s range.
TimezoneOffsetColon,
/// Offset from the local time to UTC (`+09:00` or `-04:00` or `Z`).
///
/// In the parser, the colon can be omitted and/or surrounded with any amount of whitespace,
/// and `Z` can be either in upper case or in lower case.
/// The offset is limited from `-24:00` to `+24:00`,
/// which is the same as [`FixedOffset`](../offset/struct.FixedOffset.html)'s range.
TimezoneOffsetColonZ,
/// Same as [`TimezoneOffsetColon`](#variant.TimezoneOffsetColon) but prints no colon.
/// Parsing allows an optional colon.
TimezoneOffset,
/// Same as [`TimezoneOffsetColonZ`](#variant.TimezoneOffsetColonZ) but prints no colon.
/// Parsing allows an optional colon.
TimezoneOffsetZ,
/// RFC 2822 date and time syntax. Commonly used for email and MIME date and time.
RFC2822,
/// RFC 3339 & ISO 8601 date and time syntax.
RFC3339,
/// Internal uses only.
///
/// This item exists so that one can add additional internal-only formatting
/// without breaking major compatibility (as enum variants cannot be selectively private).
Internal(InternalFixed),
}
/// An opaque type representing fixed-format item types for internal uses only.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct InternalFixed {
val: InternalInternal,
}
#[derive(Debug, Clone, PartialEq, Eq)]
enum InternalInternal {
/// Same as [`TimezoneOffsetColonZ`](#variant.TimezoneOffsetColonZ), but
/// allows missing minutes (per [ISO 8601][iso8601]).
///
/// # Panics
///
/// If you try to use this for printing.
///
TimezoneOffsetPermissive,
/// Same as [`Nanosecond`](#variant.Nanosecond) but the accuracy is fixed to 3 and there is no leading dot.
Nanosecond3NoDot,
/// Same as [`Nanosecond`](#variant.Nanosecond) but the accuracy is fixed to 6 and there is no leading dot.
Nanosecond6NoDot,
/// Same as [`Nanosecond`](#variant.Nanosecond) but the accuracy is fixed to 9 and there is no leading dot.
Nanosecond9NoDot,
}
/// A single formatting item. This is used for both formatting and parsing.
#[derive(Clone, PartialEq, Eq, Debug)]
pub enum Item<'a> {
/// A literally printed and parsed text.
Literal(&'a str),
/// Same as `Literal` but with the string owned by the item.
#[cfg(any(feature = "alloc", feature = "std", test))]
OwnedLiteral(Box<str>),
/// Whitespace. Prints literally but reads zero or more whitespace.
Space(&'a str),
/// Same as `Space` but with the string owned by the item.
#[cfg(any(feature = "alloc", feature = "std", test))]
OwnedSpace(Box<str>),
/// Numeric item. Can be optionally padded to the maximal length (if any) when formatting;
/// the parser simply ignores any padded whitespace and zeroes.
Numeric(Numeric, Pad),
/// Fixed-format item.
Fixed(Fixed),
/// Issues a formatting error. Used to signal an invalid format string.
Error,
}
macro_rules! lit {
($x:expr) => {
Item::Literal($x)
};
}
macro_rules! sp {
($x:expr) => {
Item::Space($x)
};
}
macro_rules! num {
($x:ident) => {
Item::Numeric(Numeric::$x, Pad::None)
};
}
macro_rules! num0 {
($x:ident) => {
Item::Numeric(Numeric::$x, Pad::Zero)
};
}
macro_rules! nums {
($x:ident) => {
Item::Numeric(Numeric::$x, Pad::Space)
};
}
macro_rules! fix {
($x:ident) => {
Item::Fixed(Fixed::$x)
};
}
macro_rules! internal_fix {
($x:ident) => {
Item::Fixed(Fixed::Internal(InternalFixed { val: InternalInternal::$x }))
};
}
/// An error from the `parse` function.
#[derive(Debug, Clone, PartialEq, Eq, Copy)]
pub struct ParseError(ParseErrorKind);
/// The category of parse error
#[derive(Debug, Clone, PartialEq, Eq, Copy)]
enum ParseErrorKind {
/// Given field is out of permitted range.
OutOfRange,
/// There is no possible date and time value with given set of fields.
///
/// This does not include the out-of-range conditions, which are trivially invalid.
/// It includes the case that there are one or more fields that are inconsistent to each other.
Impossible,
/// Given set of fields is not enough to make a requested date and time value.
///
/// Note that there *may* be a case that given fields constrain the possible values so much
/// that there is a unique possible value. Chrono only tries to be correct for
/// most useful sets of fields however, as such constraint solving can be expensive.
NotEnough,
/// The input string has some invalid character sequence for given formatting items.
Invalid,
/// The input string has been prematurely ended.
TooShort,
/// All formatting items have been read but there is a remaining input.
TooLong,
/// There was an error on the formatting string, or there were non-supported formating items.
BadFormat,
}
/// Same as `Result<T, ParseError>`.
pub type ParseResult<T> = Result<T, ParseError>;
impl fmt::Display for ParseError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self.0 {
ParseErrorKind::OutOfRange => write!(f, "input is out of range"),
ParseErrorKind::Impossible => write!(f, "no possible date and time matching input"),
ParseErrorKind::NotEnough => write!(f, "input is not enough for unique date and time"),
ParseErrorKind::Invalid => write!(f, "input contains invalid characters"),
ParseErrorKind::TooShort => write!(f, "premature end of input"),
ParseErrorKind::TooLong => write!(f, "trailing input"),
ParseErrorKind::BadFormat => write!(f, "bad or unsupported format string"),
}
}
}
#[cfg(any(feature = "std", test))]
impl Error for ParseError {
#[allow(deprecated)]
fn description(&self) -> &str {
"parser error, see to_string() for details"
}
}
// to be used in this module and submodules
const OUT_OF_RANGE: ParseError = ParseError(ParseErrorKind::OutOfRange);
const IMPOSSIBLE: ParseError = ParseError(ParseErrorKind::Impossible);
const NOT_ENOUGH: ParseError = ParseError(ParseErrorKind::NotEnough);
const INVALID: ParseError = ParseError(ParseErrorKind::Invalid);
const TOO_SHORT: ParseError = ParseError(ParseErrorKind::TooShort);
const TOO_LONG: ParseError = ParseError(ParseErrorKind::TooLong);
const BAD_FORMAT: ParseError = ParseError(ParseErrorKind::BadFormat);
/// Formats single formatting item
#[cfg(any(feature = "alloc", feature = "std", test))]
pub fn format_item<'a>(
w: &mut fmt::Formatter,
date: Option<&NaiveDate>,
time: Option<&NaiveTime>,
off: Option<&(String, FixedOffset)>,
item: &Item<'a>,
) -> fmt::Result {
let mut result = String::new();
format_inner(&mut result, date, time, off, item, None)?;
w.pad(&result)
}
#[cfg(any(feature = "alloc", feature = "std", test))]
fn format_inner<'a>(
result: &mut String,
date: Option<&NaiveDate>,
time: Option<&NaiveTime>,
off: Option<&(String, FixedOffset)>,
item: &Item<'a>,
_locale: Option<Locale>,
) -> fmt::Result {
#[cfg(feature = "unstable-locales")]
let (short_months, long_months, short_weekdays, long_weekdays, am_pm, am_pm_lowercase) = {
let locale = _locale.unwrap_or(Locale::POSIX);
let am_pm = locales::am_pm(locale);
(
locales::short_months(locale),
locales::long_months(locale),
locales::short_weekdays(locale),
locales::long_weekdays(locale),
am_pm,
&[am_pm[0].to_lowercase(), am_pm[1].to_lowercase()],
)
};
#[cfg(not(feature = "unstable-locales"))]
let (short_months, long_months, short_weekdays, long_weekdays, am_pm, am_pm_lowercase) = {
(
&["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"],
&[
"January",
"February",
"March",
"April",
"May",
"June",
"July",
"August",
"September",
"October",
"November",
"December",
],
&["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"],
&["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"],
&["AM", "PM"],
&["am", "pm"],
)
};
use core::fmt::Write;
use div::{div_floor, mod_floor};
match *item {
Item::Literal(s) | Item::Space(s) => result.push_str(s),
#[cfg(any(feature = "alloc", feature = "std", test))]
Item::OwnedLiteral(ref s) | Item::OwnedSpace(ref s) => result.push_str(s),
Item::Numeric(ref spec, ref pad) => {
use self::Numeric::*;
let week_from_sun = |d: &NaiveDate| {
(d.ordinal() as i32 - d.weekday().num_days_from_sunday() as i32 + 7) / 7
};
let week_from_mon = |d: &NaiveDate| {
(d.ordinal() as i32 - d.weekday().num_days_from_monday() as i32 + 7) / 7
};
let (width, v) = match *spec {
Year => (4, date.map(|d| i64::from(d.year()))),
YearDiv100 => (2, date.map(|d| div_floor(i64::from(d.year()), 100))),
YearMod100 => (2, date.map(|d| mod_floor(i64::from(d.year()), 100))),
IsoYear => (4, date.map(|d| i64::from(d.iso_week().year()))),
IsoYearDiv100 => (2, date.map(|d| div_floor(i64::from(d.iso_week().year()), 100))),
IsoYearMod100 => (2, date.map(|d| mod_floor(i64::from(d.iso_week().year()), 100))),
Month => (2, date.map(|d| i64::from(d.month()))),
Day => (2, date.map(|d| i64::from(d.day()))),
WeekFromSun => (2, date.map(|d| i64::from(week_from_sun(d)))),
WeekFromMon => (2, date.map(|d| i64::from(week_from_mon(d)))),
IsoWeek => (2, date.map(|d| i64::from(d.iso_week().week()))),
NumDaysFromSun => (1, date.map(|d| i64::from(d.weekday().num_days_from_sunday()))),
WeekdayFromMon => (1, date.map(|d| i64::from(d.weekday().number_from_monday()))),
Ordinal => (3, date.map(|d| i64::from(d.ordinal()))),
Hour => (2, time.map(|t| i64::from(t.hour()))),
Hour12 => (2, time.map(|t| i64::from(t.hour12().1))),
Minute => (2, time.map(|t| i64::from(t.minute()))),
Second => (2, time.map(|t| i64::from(t.second() + t.nanosecond() / 1_000_000_000))),
Nanosecond => (9, time.map(|t| i64::from(t.nanosecond() % 1_000_000_000))),
Timestamp => (
1,
match (date, time, off) {
(Some(d), Some(t), None) => Some(d.and_time(*t).timestamp()),
(Some(d), Some(t), Some(&(_, off))) => {
Some((d.and_time(*t) - off).timestamp())
}
(_, _, _) => None,
},
),
// for the future expansion
Internal(ref int) => match int._dummy {},
};
if let Some(v) = v {
if (spec == &Year || spec == &IsoYear) && !(0 <= v && v < 10_000) {
// non-four-digit years require an explicit sign as per ISO 8601
match *pad {
Pad::None => write!(result, "{:+}", v),
Pad::Zero => write!(result, "{:+01$}", v, width + 1),
Pad::Space => write!(result, "{:+1$}", v, width + 1),
}
} else {
match *pad {
Pad::None => write!(result, "{}", v),
Pad::Zero => write!(result, "{:01$}", v, width),
Pad::Space => write!(result, "{:1$}", v, width),
}
}?
} else {
return Err(fmt::Error); // insufficient arguments for given format
}
}
Item::Fixed(ref spec) => {
use self::Fixed::*;
/// Prints an offset from UTC in the format of `+HHMM` or `+HH:MM`.
/// `Z` instead of `+00[:]00` is allowed when `allow_zulu` is true.
fn write_local_minus_utc(
result: &mut String,
off: FixedOffset,
allow_zulu: bool,
use_colon: bool,
) -> fmt::Result {
let off = off.local_minus_utc();
if !allow_zulu || off != 0 {
let (sign, off) = if off < 0 { ('-', -off) } else { ('+', off) };
if use_colon {
write!(result, "{}{:02}:{:02}", sign, off / 3600, off / 60 % 60)
} else {
write!(result, "{}{:02}{:02}", sign, off / 3600, off / 60 % 60)
}
} else {
result.push_str("Z");
Ok(())
}
}
let ret =
match *spec {
ShortMonthName => date.map(|d| {
result.push_str(short_months[d.month0() as usize]);
Ok(())
}),
LongMonthName => date.map(|d| {
result.push_str(long_months[d.month0() as usize]);
Ok(())
}),
ShortWeekdayName => date.map(|d| {
result
.push_str(short_weekdays[d.weekday().num_days_from_sunday() as usize]);
Ok(())
}),
LongWeekdayName => date.map(|d| {
result.push_str(long_weekdays[d.weekday().num_days_from_sunday() as usize]);
Ok(())
}),
LowerAmPm => time.map(|t| {
#[cfg_attr(feature = "cargo-clippy", allow(useless_asref))]
{
result.push_str(if t.hour12().0 {
am_pm_lowercase[1].as_ref()
} else {
am_pm_lowercase[0].as_ref()
});
}
Ok(())
}),
UpperAmPm => time.map(|t| {
result.push_str(if t.hour12().0 { am_pm[1] } else { am_pm[0] });
Ok(())
}),
Nanosecond => time.map(|t| {
let nano = t.nanosecond() % 1_000_000_000;
if nano == 0 {
Ok(())
} else if nano % 1_000_000 == 0 {
write!(result, ".{:03}", nano / 1_000_000)
} else if nano % 1_000 == 0 {
write!(result, ".{:06}", nano / 1_000)
} else {
write!(result, ".{:09}", nano)
}
}),
Nanosecond3 => time.map(|t| {
let nano = t.nanosecond() % 1_000_000_000;
write!(result, ".{:03}", nano / 1_000_000)
}),
Nanosecond6 => time.map(|t| {
let nano = t.nanosecond() % 1_000_000_000;
write!(result, ".{:06}", nano / 1_000)
}),
Nanosecond9 => time.map(|t| {
let nano = t.nanosecond() % 1_000_000_000;
write!(result, ".{:09}", nano)
}),
Internal(InternalFixed { val: InternalInternal::Nanosecond3NoDot }) => time
.map(|t| {
let nano = t.nanosecond() % 1_000_000_000;
write!(result, "{:03}", nano / 1_000_000)
}),
Internal(InternalFixed { val: InternalInternal::Nanosecond6NoDot }) => time
.map(|t| {
let nano = t.nanosecond() % 1_000_000_000;
write!(result, "{:06}", nano / 1_000)
}),
Internal(InternalFixed { val: InternalInternal::Nanosecond9NoDot }) => time
.map(|t| {
let nano = t.nanosecond() % 1_000_000_000;
write!(result, "{:09}", nano)
}),
TimezoneName => off.map(|&(ref name, _)| {
result.push_str(name);
Ok(())
}),
TimezoneOffsetColon => {
off.map(|&(_, off)| write_local_minus_utc(result, off, false, true))
}
TimezoneOffsetColonZ => {
off.map(|&(_, off)| write_local_minus_utc(result, off, true, true))
}
TimezoneOffset => {
off.map(|&(_, off)| write_local_minus_utc(result, off, false, false))
}
TimezoneOffsetZ => {
off.map(|&(_, off)| write_local_minus_utc(result, off, true, false))
}
Internal(InternalFixed { val: InternalInternal::TimezoneOffsetPermissive }) => {
panic!("Do not try to write %#z it is undefined")
}
RFC2822 =>
// same as `%a, %d %b %Y %H:%M:%S %z`
{
if let (Some(d), Some(t), Some(&(_, off))) = (date, time, off) {
let sec = t.second() + t.nanosecond() / 1_000_000_000;
write!(
result,
"{}, {:02} {} {:04} {:02}:{:02}:{:02} ",
short_weekdays[d.weekday().num_days_from_sunday() as usize],
d.day(),
short_months[d.month0() as usize],
d.year(),
t.hour(),
t.minute(),
sec
)?;
Some(write_local_minus_utc(result, off, false, false))
} else {
None
}
}
RFC3339 =>
// same as `%Y-%m-%dT%H:%M:%S%.f%:z`
{
if let (Some(d), Some(t), Some(&(_, off))) = (date, time, off) {
// reuse `Debug` impls which already print ISO 8601 format.
// this is faster in this way.
write!(result, "{:?}T{:?}", d, t)?;
Some(write_local_minus_utc(result, off, false, true))
} else {
None
}
}
};
match ret {
Some(ret) => ret?,
None => return Err(fmt::Error), // insufficient arguments for given format
}
}
Item::Error => return Err(fmt::Error),
}
Ok(())
}
/// Tries to format given arguments with given formatting items.
/// Internally used by `DelayedFormat`.
#[cfg(any(feature = "alloc", feature = "std", test))]
pub fn format<'a, I, B>(
w: &mut fmt::Formatter,
date: Option<&NaiveDate>,
time: Option<&NaiveTime>,
off: Option<&(String, FixedOffset)>,
items: I,
) -> fmt::Result
where
I: Iterator<Item = B> + Clone,
B: Borrow<Item<'a>>,
{
let mut result = String::new();
for item in items {
format_inner(&mut result, date, time, off, item.borrow(), None)?;
}
w.pad(&result)
}
mod parsed;
// due to the size of parsing routines, they are in separate modules.
mod parse;
mod scan;
pub mod strftime;
/// A *temporary* object which can be used as an argument to `format!` or others.
/// This is normally constructed via `format` methods of each date and time type.
#[cfg(any(feature = "alloc", feature = "std", test))]
#[derive(Debug)]
pub struct DelayedFormat<I> {
/// The date view, if any.
date: Option<NaiveDate>,
/// The time view, if any.
time: Option<NaiveTime>,
/// The name and local-to-UTC difference for the offset (timezone), if any.
off: Option<(String, FixedOffset)>,
/// An iterator returning formatting items.
items: I,
/// Locale used for text.
locale: Option<Locale>,
}
#[cfg(any(feature = "alloc", feature = "std", test))]
impl<'a, I: Iterator<Item = B> + Clone, B: Borrow<Item<'a>>> DelayedFormat<I> {
/// Makes a new `DelayedFormat` value out of local date and time.
pub fn new(date: Option<NaiveDate>, time: Option<NaiveTime>, items: I) -> DelayedFormat<I> {
DelayedFormat { date: date, time: time, off: None, items: items, locale: None }
}
/// Makes a new `DelayedFormat` value out of local date and time and UTC offset.
pub fn new_with_offset<Off>(
date: Option<NaiveDate>,
time: Option<NaiveTime>,
offset: &Off,
items: I,
) -> DelayedFormat<I>
where
Off: Offset + fmt::Display,
{
let name_and_diff = (offset.to_string(), offset.fix());
DelayedFormat {
date: date,
time: time,
off: Some(name_and_diff),
items: items,
locale: None,
}
}
/// Makes a new `DelayedFormat` value out of local date and time and locale.
#[cfg(feature = "unstable-locales")]
pub fn new_with_locale(
date: Option<NaiveDate>,
time: Option<NaiveTime>,
items: I,
locale: Locale,
) -> DelayedFormat<I> {
DelayedFormat { date: date, time: time, off: None, items: items, locale: Some(locale) }
}
/// Makes a new `DelayedFormat` value out of local date and time, UTC offset and locale.
#[cfg(feature = "unstable-locales")]
pub fn new_with_offset_and_locale<Off>(
date: Option<NaiveDate>,
time: Option<NaiveTime>,
offset: &Off,
items: I,
locale: Locale,
) -> DelayedFormat<I>
where
Off: Offset + fmt::Display,
{
let name_and_diff = (offset.to_string(), offset.fix());
DelayedFormat {
date: date,
time: time,
off: Some(name_and_diff),
items: items,
locale: Some(locale),
}
}
}
#[cfg(any(feature = "alloc", feature = "std", test))]
impl<'a, I: Iterator<Item = B> + Clone, B: Borrow<Item<'a>>> fmt::Display for DelayedFormat<I> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
#[cfg(feature = "unstable-locales")]
{
if let Some(locale) = self.locale {
return format_localized(
f,
self.date.as_ref(),
self.time.as_ref(),
self.off.as_ref(),
self.items.clone(),
locale,
);
}
}
format(f, self.date.as_ref(), self.time.as_ref(), self.off.as_ref(), self.items.clone())
}
}
// this implementation is here only because we need some private code from `scan`
/// Parsing a `str` into a `Weekday` uses the format [`%W`](./format/strftime/index.html).
///
/// # Example
///
/// ~~~~
/// use chrono::Weekday;
///
/// assert_eq!("Sunday".parse::<Weekday>(), Ok(Weekday::Sun));
/// assert!("any day".parse::<Weekday>().is_err());
/// ~~~~
///
/// The parsing is case-insensitive.
///
/// ~~~~
/// # use chrono::Weekday;
/// assert_eq!("mON".parse::<Weekday>(), Ok(Weekday::Mon));
/// ~~~~
///
/// Only the shortest form (e.g. `sun`) and the longest form (e.g. `sunday`) is accepted.
///
/// ~~~~
/// # use chrono::Weekday;
/// assert!("thurs".parse::<Weekday>().is_err());
/// ~~~~
impl FromStr for Weekday {
type Err = ParseWeekdayError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
if let Ok(("", w)) = scan::short_or_long_weekday(s) {
Ok(w)
} else {
Err(ParseWeekdayError { _dummy: () })
}
}
}
/// Formats single formatting item
#[cfg(feature = "unstable-locales")]
pub fn format_item_localized<'a>(
w: &mut fmt::Formatter,
date: Option<&NaiveDate>,
time: Option<&NaiveTime>,
off: Option<&(String, FixedOffset)>,
item: &Item<'a>,
locale: Locale,
) -> fmt::Result {
let mut result = String::new();
format_inner(&mut result, date, time, off, item, Some(locale))?;
w.pad(&result)
}
/// Tries to format given arguments with given formatting items.
/// Internally used by `DelayedFormat`.
#[cfg(feature = "unstable-locales")]
pub fn format_localized<'a, I, B>(
w: &mut fmt::Formatter,
date: Option<&NaiveDate>,
time: Option<&NaiveTime>,
off: Option<&(String, FixedOffset)>,
items: I,
locale: Locale,
) -> fmt::Result
where
I: Iterator<Item = B> + Clone,
B: Borrow<Item<'a>>,
{
let mut result = String::new();
for item in items {
format_inner(&mut result, date, time, off, item.borrow(), Some(locale))?;
}
w.pad(&result)
}
/// Parsing a `str` into a `Month` uses the format [`%W`](./format/strftime/index.html).
///
/// # Example
///
/// ~~~~
/// use chrono::Month;
///
/// assert_eq!("January".parse::<Month>(), Ok(Month::January));
/// assert!("any day".parse::<Month>().is_err());
/// ~~~~
///
/// The parsing is case-insensitive.
///
/// ~~~~
/// # use chrono::Month;
/// assert_eq!("fEbruARy".parse::<Month>(), Ok(Month::February));
/// ~~~~
///
/// Only the shortest form (e.g. `jan`) and the longest form (e.g. `january`) is accepted.
///
/// ~~~~
/// # use chrono::Month;
/// assert!("septem".parse::<Month>().is_err());
/// assert!("Augustin".parse::<Month>().is_err());
/// ~~~~
impl FromStr for Month {
type Err = ParseMonthError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
if let Ok(("", w)) = scan::short_or_long_month0(s) {
match w {
0 => Ok(Month::January),
1 => Ok(Month::February),
2 => Ok(Month::March),
3 => Ok(Month::April),
4 => Ok(Month::May),
5 => Ok(Month::June),
6 => Ok(Month::July),
7 => Ok(Month::August),
8 => Ok(Month::September),
9 => Ok(Month::October),
10 => Ok(Month::November),
11 => Ok(Month::December),
_ => Err(ParseMonthError { _dummy: () }),
}
} else {
Err(ParseMonthError { _dummy: () })
}
}
}