1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552
// 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**,
//! which are just an [`Iterator`](https://doc.rust-lang.org/std/iter/trait.Iterator.html) of
//! the [`Item`](./enum.Item.html) type.
//! They are generated from more readable **format strings**;
//! currently Chrono supports a built-in syntax closely resembling
//! C's `strftime` format. The available options can be found [here](./strftime/index.html).
//!
//! # Example
#![cfg_attr(not(feature = "std"), doc = "```ignore")]
#![cfg_attr(feature = "std", doc = "```rust")]
//! use chrono::{NaiveDateTime, TimeZone, Utc};
//!
//! let date_time = Utc.with_ymd_and_hms(2020, 11, 10, 0, 1, 32).unwrap();
//!
//! let formatted = format!("{}", date_time.format("%Y-%m-%d %H:%M:%S"));
//! assert_eq!(formatted, "2020-11-10 00:01:32");
//!
//! let parsed = NaiveDateTime::parse_from_str(&formatted, "%Y-%m-%d %H:%M:%S")?.and_utc();
//! assert_eq!(parsed, date_time);
//! # Ok::<(), chrono::ParseError>(())
//! ```
#[cfg(all(not(feature = "std"), feature = "alloc"))]
use alloc::boxed::Box;
use core::fmt;
use core::str::FromStr;
#[cfg(feature = "std")]
use std::error::Error;
use crate::{Month, ParseMonthError, ParseWeekdayError, Weekday};
mod formatting;
mod parsed;
// due to the size of parsing routines, they are in separate modules.
mod parse;
pub(crate) mod scan;
pub mod strftime;
#[allow(unused)]
// TODO: remove '#[allow(unused)]' once we use this module for parsing or something else that does
// not require `alloc`.
pub(crate) mod locales;
pub(crate) use formatting::write_hundreds;
#[cfg(feature = "alloc")]
pub(crate) use formatting::write_rfc2822;
#[cfg(any(feature = "alloc", feature = "serde", feature = "rustc-serialize"))]
pub(crate) use formatting::write_rfc3339;
pub use formatting::SecondsFormat;
#[cfg(feature = "alloc")]
#[allow(deprecated)]
pub use formatting::{format, format_item, DelayedFormat};
#[cfg(feature = "unstable-locales")]
pub use locales::Locale;
pub(crate) use parse::parse_rfc3339;
pub use parse::{parse, parse_and_remainder};
pub use parsed::Parsed;
pub use strftime::StrftimeItems;
/// An uninhabited type used for `InternalNumeric` and `InternalFixed` below.
#[derive(Clone, PartialEq, Eq, Hash)]
enum Void {}
/// Padding characters for numeric items.
#[derive(Copy, Clone, PartialEq, Eq, Debug, Hash)]
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, Hash)]
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.
#[derive(Clone, Eq, Hash, PartialEq)]
pub struct InternalNumeric {
_dummy: Void,
}
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, Hash)]
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 with seconds (`+09:00:00` or `-04:00:00` or `+00:00:00`).
///
/// In the parser, the colon can be omitted and/or surrounded with any amount of whitespace.
/// The offset is limited from `-24:00:00` to `+24:00:00`,
/// which is the same as [`FixedOffset`](../offset/struct.FixedOffset.html)'s range.
TimezoneOffsetDoubleColon,
/// Offset from the local time to UTC without minutes (`+09` or `-04` or `+00`).
///
/// In the parser, the colon can be omitted and/or surrounded with any amount of whitespace.
/// The offset is limited from `-24` to `+24`,
/// which is the same as [`FixedOffset`](../offset/struct.FixedOffset.html)'s range.
TimezoneOffsetTripleColon,
/// 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, Hash)]
pub struct InternalFixed {
val: InternalInternal,
}
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
enum InternalInternal {
/// Same as [`TimezoneOffsetColonZ`](#variant.TimezoneOffsetColonZ), but
/// allows missing minutes (per [ISO 8601][iso8601]).
///
/// # Panics
///
/// If you try to use this for printing.
///
/// [iso8601]: https://en.wikipedia.org/wiki/ISO_8601#Time_offsets_from_UTC
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,
}
/// Type for specifying the format of UTC offsets.
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub struct OffsetFormat {
/// See `OffsetPrecision`.
pub precision: OffsetPrecision,
/// Separator between hours, minutes and seconds.
pub colons: Colons,
/// Represent `+00:00` as `Z`.
pub allow_zulu: bool,
/// Pad the hour value to two digits.
pub padding: Pad,
}
/// The precision of an offset from UTC formatting item.
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub enum OffsetPrecision {
/// Format offset from UTC as only hours. Not recommended, it is not uncommon for timezones to
/// have an offset of 30 minutes, 15 minutes, etc.
/// Any minutes and seconds get truncated.
Hours,
/// Format offset from UTC as hours and minutes.
/// Any seconds will be rounded to the nearest minute.
Minutes,
/// Format offset from UTC as hours, minutes and seconds.
Seconds,
/// Format offset from UTC as hours, and optionally with minutes.
/// Any seconds will be rounded to the nearest minute.
OptionalMinutes,
/// Format offset from UTC as hours and minutes, and optionally seconds.
OptionalSeconds,
/// Format offset from UTC as hours and optionally minutes and seconds.
OptionalMinutesAndSeconds,
}
/// The separator between hours and minutes in an offset.
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub enum Colons {
/// No separator
None,
/// Colon (`:`) as separator
Colon,
/// No separator when formatting, colon allowed when parsing.
Maybe,
}
/// A single formatting item. This is used for both formatting and parsing.
#[derive(Clone, PartialEq, Eq, Debug, Hash)]
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(feature = "alloc")]
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(feature = "alloc")]
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,
}
const fn num(numeric: Numeric) -> Item<'static> {
Item::Numeric(numeric, Pad::None)
}
const fn num0(numeric: Numeric) -> Item<'static> {
Item::Numeric(numeric, Pad::Zero)
}
const fn nums(numeric: Numeric) -> Item<'static> {
Item::Numeric(numeric, Pad::Space)
}
const fn fixed(fixed: Fixed) -> Item<'static> {
Item::Fixed(fixed)
}
const fn internal_fixed(val: InternalInternal) -> Item<'static> {
Item::Fixed(Fixed::Internal(InternalFixed { val }))
}
impl<'a> Item<'a> {
/// Convert items that contain a reference to the format string into an owned variant.
#[cfg(any(feature = "alloc", feature = "std"))]
pub fn to_owned(self) -> Item<'static> {
match self {
Item::Literal(s) => Item::OwnedLiteral(Box::from(s)),
Item::Space(s) => Item::OwnedSpace(Box::from(s)),
Item::Numeric(n, p) => Item::Numeric(n, p),
Item::Fixed(f) => Item::Fixed(f),
Item::OwnedLiteral(l) => Item::OwnedLiteral(l),
Item::OwnedSpace(s) => Item::OwnedSpace(s),
Item::Error => Item::Error,
}
}
}
/// An error from the `parse` function.
#[derive(Debug, Clone, PartialEq, Eq, Copy, Hash)]
pub struct ParseError(ParseErrorKind);
impl ParseError {
/// The category of parse error
pub const fn kind(&self) -> ParseErrorKind {
self.0
}
}
/// The category of parse error
#[allow(clippy::manual_non_exhaustive)]
#[derive(Debug, Clone, PartialEq, Eq, Copy, Hash)]
pub 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,
// TODO: Change this to `#[non_exhaustive]` (on the enum) with the next breaking release.
#[doc(hidden)]
__Nonexhaustive,
}
/// 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"),
_ => unreachable!(),
}
}
}
#[cfg(feature = "std")]
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
pub(crate) 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);
pub(crate) const TOO_LONG: ParseError = ParseError(ParseErrorKind::TooLong);
const BAD_FORMAT: ParseError = ParseError(ParseErrorKind::BadFormat);
// this implementation is here only because we need some private code from `scan`
/// Parsing a `str` into a `Weekday` uses the format [`%A`](./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: () })
}
}
}
/// Parsing a `str` into a `Month` uses the format [`%B`](./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: () })
}
}
}