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diff --git a/vendor/chrono/README.md b/vendor/chrono/README.md index 5a5a74b42..ad9591889 100644 --- a/vendor/chrono/README.md +++ b/vendor/chrono/README.md @@ -6,7 +6,7 @@ [![Chrono on docs.rs][docsrs-image]][docsrs] [![Join the chat at https://gitter.im/chrono-rs/chrono][gitter-image]][gitter] -[gh-image]: https://github.com/chronotope/chrono/workflows/test/badge.svg +[gh-image]: https://github.com/chronotope/chrono/actions/workflows/test.yml/badge.svg [gh-checks]: https://github.com/chronotope/chrono/actions?query=workflow%3Atest [cratesio-image]: https://img.shields.io/crates/v/chrono.svg [cratesio]: https://crates.io/crates/chrono @@ -31,365 +31,6 @@ which Chrono builds upon and should acknowledge: * Dietrich Epp's [datetime-rs](https://github.com/depp/datetime-rs) * Luis de Bethencourt's [rust-datetime](https://github.com/luisbg/rust-datetime) -Any significant changes to Chrono are documented in -the [`CHANGELOG.md`](https://github.com/chronotope/chrono/blob/main/CHANGELOG.md) file. - - -## Usage - -Put this in your `Cargo.toml`: - -```toml -[dependencies] -chrono = "0.4" -``` - -### Features - -Chrono supports various runtime environments and operating systems, and has -several features that may be enabled or disabled. - -Default features: - -- `alloc`: Enable features that depend on allocation (primarily string formatting) -- `std`: Enables functionality that depends on the standard library. This - is a superset of `alloc` and adds interoperation with standard library types - and traits. -- `clock`: enables reading the system time (`now`), independent of whether - `std::time::SystemTime` is present, depends on having a libc. - -Optional features: - -- `wasmbind`: Enable integration with [wasm-bindgen][] and its `js-sys` project -- [`serde`][]: Enable serialization/deserialization via serde. -- `unstable-locales`: Enable localization. This adds various methods with a - `_localized` suffix. The implementation and API may change or even be - removed in a patch release. Feedback welcome. - -[`serde`]: https://github.com/serde-rs/serde -[wasm-bindgen]: https://github.com/rustwasm/wasm-bindgen - -See the [cargo docs][] for examples of specifying features. - -[cargo docs]: https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#choosing-features - -## Overview - -### Duration - -Chrono currently uses its own [`Duration`] type to represent the magnitude -of a time span. Since this has the same name as the newer, standard type for -duration, the reference will refer this type as `OldDuration`. - -Note that this is an "accurate" duration represented as seconds and -nanoseconds and does not represent "nominal" components such as days or -months. - -When the `oldtime` feature is enabled, [`Duration`] is an alias for the -[`time::Duration`](https://docs.rs/time/0.1.40/time/struct.Duration.html) -type from v0.1 of the time crate. time v0.1 is deprecated, so new code -should disable the `oldtime` feature and use the `chrono::Duration` type -instead. The `oldtime` feature is enabled by default for backwards -compatibility, but future versions of Chrono are likely to remove the -feature entirely. - -Chrono does not yet natively support -the standard [`Duration`](https://doc.rust-lang.org/std/time/struct.Duration.html) type, -but it will be supported in the future. -Meanwhile you can convert between two types with -[`Duration::from_std`](https://docs.rs/time/0.1.40/time/struct.Duration.html#method.from_std) -and -[`Duration::to_std`](https://docs.rs/time/0.1.40/time/struct.Duration.html#method.to_std) -methods. - -### Date and Time - -Chrono provides a -[**`DateTime`**](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html) -type to represent a date and a time in a timezone. - -For more abstract moment-in-time tracking such as internal timekeeping -that is unconcerned with timezones, consider -[`time::SystemTime`](https://doc.rust-lang.org/std/time/struct.SystemTime.html), -which tracks your system clock, or -[`time::Instant`](https://doc.rust-lang.org/std/time/struct.Instant.html), which -is an opaque but monotonically-increasing representation of a moment in time. - -`DateTime` is timezone-aware and must be constructed from -the [**`TimeZone`**](https://docs.rs/chrono/0.4/chrono/offset/trait.TimeZone.html) object, -which defines how the local date is converted to and back from the UTC date. -There are three well-known `TimeZone` implementations: - -* [**`Utc`**](https://docs.rs/chrono/0.4/chrono/offset/struct.Utc.html) specifies the UTC time zone. It is most efficient. - -* [**`Local`**](https://docs.rs/chrono/0.4/chrono/offset/struct.Local.html) specifies the system local time zone. - -* [**`FixedOffset`**](https://docs.rs/chrono/0.4/chrono/offset/struct.FixedOffset.html) specifies - an arbitrary, fixed time zone such as UTC+09:00 or UTC-10:30. - This often results from the parsed textual date and time. - Since it stores the most information and does not depend on the system environment, - you would want to normalize other `TimeZone`s into this type. - -`DateTime`s with different `TimeZone` types are distinct and do not mix, -but can be converted to each other using -the [`DateTime::with_timezone`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.with_timezone) method. - -You can get the current date and time in the UTC time zone -([`Utc::now()`](https://docs.rs/chrono/0.4/chrono/offset/struct.Utc.html#method.now)) -or in the local time zone -([`Local::now()`](https://docs.rs/chrono/0.4/chrono/offset/struct.Local.html#method.now)). - -```rust -use chrono::prelude::*; - -let utc: DateTime<Utc> = Utc::now(); // e.g. `2014-11-28T12:45:59.324310806Z` -let local: DateTime<Local> = Local::now(); // e.g. `2014-11-28T21:45:59.324310806+09:00` -``` - -Alternatively, you can create your own date and time. -This is a bit verbose due to Rust's lack of function and method overloading, -but in turn we get a rich combination of initialization methods. - -```rust -use chrono::prelude::*; -use chrono::offset::LocalResult; - -let dt = Utc.ymd(2014, 7, 8).and_hms(9, 10, 11); // `2014-07-08T09:10:11Z` -// July 8 is 188th day of the year 2014 (`o` for "ordinal") -assert_eq!(dt, Utc.yo(2014, 189).and_hms(9, 10, 11)); -// July 8 is Tuesday in ISO week 28 of the year 2014. -assert_eq!(dt, Utc.isoywd(2014, 28, Weekday::Tue).and_hms(9, 10, 11)); - -let dt = Utc.ymd(2014, 7, 8).and_hms_milli(9, 10, 11, 12); // `2014-07-08T09:10:11.012Z` -assert_eq!(dt, Utc.ymd(2014, 7, 8).and_hms_micro(9, 10, 11, 12_000)); -assert_eq!(dt, Utc.ymd(2014, 7, 8).and_hms_nano(9, 10, 11, 12_000_000)); - -// dynamic verification -assert_eq!(Utc.ymd_opt(2014, 7, 8).and_hms_opt(21, 15, 33), - LocalResult::Single(Utc.ymd(2014, 7, 8).and_hms(21, 15, 33))); -assert_eq!(Utc.ymd_opt(2014, 7, 8).and_hms_opt(80, 15, 33), LocalResult::None); -assert_eq!(Utc.ymd_opt(2014, 7, 38).and_hms_opt(21, 15, 33), LocalResult::None); - -// other time zone objects can be used to construct a local datetime. -// obviously, `local_dt` is normally different from `dt`, but `fixed_dt` should be identical. -let local_dt = Local.ymd(2014, 7, 8).and_hms_milli(9, 10, 11, 12); -let fixed_dt = FixedOffset::east(9 * 3600).ymd(2014, 7, 8).and_hms_milli(18, 10, 11, 12); -assert_eq!(dt, fixed_dt); -``` - -Various properties are available to the date and time, and can be altered individually. -Most of them are defined in the traits [`Datelike`](https://docs.rs/chrono/0.4/chrono/trait.Datelike.html) and -[`Timelike`](https://docs.rs/chrono/0.4/chrono/trait.Timelike.html) which you should `use` before. -Addition and subtraction is also supported. -The following illustrates most supported operations to the date and time: - -```rust - -use chrono::prelude::*; -use chrono::Duration; - -// assume this returned `2014-11-28T21:45:59.324310806+09:00`: -let dt = FixedOffset::east(9*3600).ymd(2014, 11, 28).and_hms_nano(21, 45, 59, 324310806); - -// property accessors -assert_eq!((dt.year(), dt.month(), dt.day()), (2014, 11, 28)); -assert_eq!((dt.month0(), dt.day0()), (10, 27)); // for unfortunate souls -assert_eq!((dt.hour(), dt.minute(), dt.second()), (21, 45, 59)); -assert_eq!(dt.weekday(), Weekday::Fri); -assert_eq!(dt.weekday().number_from_monday(), 5); // Mon=1, ..., Sun=7 -assert_eq!(dt.ordinal(), 332); // the day of year -assert_eq!(dt.num_days_from_ce(), 735565); // the number of days from and including Jan 1, 1 - -// time zone accessor and manipulation -assert_eq!(dt.offset().fix().local_minus_utc(), 9 * 3600); -assert_eq!(dt.timezone(), FixedOffset::east(9 * 3600)); -assert_eq!(dt.with_timezone(&Utc), Utc.ymd(2014, 11, 28).and_hms_nano(12, 45, 59, 324310806)); - -// a sample of property manipulations (validates dynamically) -assert_eq!(dt.with_day(29).unwrap().weekday(), Weekday::Sat); // 2014-11-29 is Saturday -assert_eq!(dt.with_day(32), None); -assert_eq!(dt.with_year(-300).unwrap().num_days_from_ce(), -109606); // November 29, 301 BCE - -// arithmetic operations -let dt1 = Utc.ymd(2014, 11, 14).and_hms(8, 9, 10); -let dt2 = Utc.ymd(2014, 11, 14).and_hms(10, 9, 8); -assert_eq!(dt1.signed_duration_since(dt2), Duration::seconds(-2 * 3600 + 2)); -assert_eq!(dt2.signed_duration_since(dt1), Duration::seconds(2 * 3600 - 2)); -assert_eq!(Utc.ymd(1970, 1, 1).and_hms(0, 0, 0) + Duration::seconds(1_000_000_000), - Utc.ymd(2001, 9, 9).and_hms(1, 46, 40)); -assert_eq!(Utc.ymd(1970, 1, 1).and_hms(0, 0, 0) - Duration::seconds(1_000_000_000), - Utc.ymd(1938, 4, 24).and_hms(22, 13, 20)); -``` - -### Formatting and Parsing - -Formatting is done via the [`format`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.format) method, -which format is equivalent to the familiar `strftime` format. - -See [`format::strftime`](https://docs.rs/chrono/0.4/chrono/format/strftime/index.html#specifiers) -documentation for full syntax and list of specifiers. - -The default `to_string` method and `{:?}` specifier also give a reasonable representation. -Chrono also provides [`to_rfc2822`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.to_rfc2822) and -[`to_rfc3339`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.to_rfc3339) methods -for well-known formats. - -Chrono now also provides date formatting in almost any language without the -help of an additional C library. This functionality is under the feature -`unstable-locales`: - -```text -chrono { version = "0.4", features = ["unstable-locales"] -``` - -The `unstable-locales` feature requires and implies at least the `alloc` feature. - -```rust -use chrono::prelude::*; - -let dt = Utc.ymd(2014, 11, 28).and_hms(12, 0, 9); -assert_eq!(dt.format("%Y-%m-%d %H:%M:%S").to_string(), "2014-11-28 12:00:09"); -assert_eq!(dt.format("%a %b %e %T %Y").to_string(), "Fri Nov 28 12:00:09 2014"); -assert_eq!(dt.format_localized("%A %e %B %Y, %T", Locale::fr_BE).to_string(), "vendredi 28 novembre 2014, 12:00:09"); -assert_eq!(dt.format("%a %b %e %T %Y").to_string(), dt.format("%c").to_string()); - -assert_eq!(dt.to_string(), "2014-11-28 12:00:09 UTC"); -assert_eq!(dt.to_rfc2822(), "Fri, 28 Nov 2014 12:00:09 +0000"); -assert_eq!(dt.to_rfc3339(), "2014-11-28T12:00:09+00:00"); -assert_eq!(format!("{:?}", dt), "2014-11-28T12:00:09Z"); - -// Note that milli/nanoseconds are only printed if they are non-zero -let dt_nano = Utc.ymd(2014, 11, 28).and_hms_nano(12, 0, 9, 1); -assert_eq!(format!("{:?}", dt_nano), "2014-11-28T12:00:09.000000001Z"); -``` - -Parsing can be done with three methods: - -1. The standard [`FromStr`](https://doc.rust-lang.org/std/str/trait.FromStr.html) trait - (and [`parse`](https://doc.rust-lang.org/std/primitive.str.html#method.parse) method - on a string) can be used for parsing `DateTime<FixedOffset>`, `DateTime<Utc>` and - `DateTime<Local>` values. This parses what the `{:?}` - ([`std::fmt::Debug`](https://doc.rust-lang.org/std/fmt/trait.Debug.html)) - format specifier prints, and requires the offset to be present. - -2. [`DateTime::parse_from_str`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.parse_from_str) parses - a date and time with offsets and returns `DateTime<FixedOffset>`. - This should be used when the offset is a part of input and the caller cannot guess that. - It *cannot* be used when the offset can be missing. - [`DateTime::parse_from_rfc2822`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.parse_from_rfc2822) - and - [`DateTime::parse_from_rfc3339`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.parse_from_rfc3339) - are similar but for well-known formats. - -3. [`Offset::datetime_from_str`](https://docs.rs/chrono/0.4/chrono/offset/trait.TimeZone.html#method.datetime_from_str) is - similar but returns `DateTime` of given offset. - When the explicit offset is missing from the input, it simply uses given offset. - It issues an error when the input contains an explicit offset different - from the current offset. - -More detailed control over the parsing process is available via -[`format`](https://docs.rs/chrono/0.4/chrono/format/index.html) module. - -```rust -use chrono::prelude::*; - -let dt = Utc.ymd(2014, 11, 28).and_hms(12, 0, 9); -let fixed_dt = dt.with_timezone(&FixedOffset::east(9*3600)); - -// method 1 -assert_eq!("2014-11-28T12:00:09Z".parse::<DateTime<Utc>>(), Ok(dt.clone())); -assert_eq!("2014-11-28T21:00:09+09:00".parse::<DateTime<Utc>>(), Ok(dt.clone())); -assert_eq!("2014-11-28T21:00:09+09:00".parse::<DateTime<FixedOffset>>(), Ok(fixed_dt.clone())); - -// method 2 -assert_eq!(DateTime::parse_from_str("2014-11-28 21:00:09 +09:00", "%Y-%m-%d %H:%M:%S %z"), - Ok(fixed_dt.clone())); -assert_eq!(DateTime::parse_from_rfc2822("Fri, 28 Nov 2014 21:00:09 +0900"), - Ok(fixed_dt.clone())); -assert_eq!(DateTime::parse_from_rfc3339("2014-11-28T21:00:09+09:00"), Ok(fixed_dt.clone())); - -// method 3 -assert_eq!(Utc.datetime_from_str("2014-11-28 12:00:09", "%Y-%m-%d %H:%M:%S"), Ok(dt.clone())); -assert_eq!(Utc.datetime_from_str("Fri Nov 28 12:00:09 2014", "%a %b %e %T %Y"), Ok(dt.clone())); - -// oops, the year is missing! -assert!(Utc.datetime_from_str("Fri Nov 28 12:00:09", "%a %b %e %T %Y").is_err()); -// oops, the format string does not include the year at all! -assert!(Utc.datetime_from_str("Fri Nov 28 12:00:09", "%a %b %e %T").is_err()); -// oops, the weekday is incorrect! -assert!(Utc.datetime_from_str("Sat Nov 28 12:00:09 2014", "%a %b %e %T %Y").is_err()); -``` - -Again : See [`format::strftime`](https://docs.rs/chrono/0.4/chrono/format/strftime/index.html#specifiers) -documentation for full syntax and list of specifiers. - -### Conversion from and to EPOCH timestamps - -Use [`Utc.timestamp(seconds, nanoseconds)`](https://docs.rs/chrono/0.4/chrono/offset/trait.TimeZone.html#method.timestamp) -to construct a [`DateTime<Utc>`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html) from a UNIX timestamp -(seconds, nanoseconds that passed since January 1st 1970). - -Use [`DateTime.timestamp`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.timestamp) to get the timestamp (in seconds) -from a [`DateTime`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html). Additionally, you can use -[`DateTime.timestamp_subsec_nanos`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.timestamp_subsec_nanos) -to get the number of additional number of nanoseconds. - -```rust -// We need the trait in scope to use Utc::timestamp(). -use chrono::{DateTime, TimeZone, Utc}; - -// Construct a datetime from epoch: -let dt = Utc.timestamp(1_500_000_000, 0); -assert_eq!(dt.to_rfc2822(), "Fri, 14 Jul 2017 02:40:00 +0000"); - -// Get epoch value from a datetime: -let dt = DateTime::parse_from_rfc2822("Fri, 14 Jul 2017 02:40:00 +0000").unwrap(); -assert_eq!(dt.timestamp(), 1_500_000_000); -``` - -### Individual date - -Chrono also provides an individual date type ([**`Date`**](https://docs.rs/chrono/0.4/chrono/struct.Date.html)). -It also has time zones attached, and have to be constructed via time zones. -Most operations available to `DateTime` are also available to `Date` whenever appropriate. - -```rust -use chrono::prelude::*; -use chrono::offset::LocalResult; - -assert_eq!(Utc::today(), Utc::now().date()); -assert_eq!(Local::today(), Local::now().date()); - -assert_eq!(Utc.ymd(2014, 11, 28).weekday(), Weekday::Fri); -assert_eq!(Utc.ymd_opt(2014, 11, 31), LocalResult::None); -assert_eq!(Utc.ymd(2014, 11, 28).and_hms_milli(7, 8, 9, 10).format("%H%M%S").to_string(), - "070809"); -``` - -There is no timezone-aware `Time` due to the lack of usefulness and also the complexity. - -`DateTime` has [`date`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.date) method -which returns a `Date` which represents its date component. -There is also a [`time`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.time) method, -which simply returns a naive local time described below. - -### Naive date and time - -Chrono provides naive counterparts to `Date`, (non-existent) `Time` and `DateTime` -as [**`NaiveDate`**](https://docs.rs/chrono/0.4/chrono/naive/struct.NaiveDate.html), -[**`NaiveTime`**](https://docs.rs/chrono/0.4/chrono/naive/struct.NaiveTime.html) and -[**`NaiveDateTime`**](https://docs.rs/chrono/0.4/chrono/naive/struct.NaiveDateTime.html) respectively. - -They have almost equivalent interfaces as their timezone-aware twins, -but are not associated to time zones obviously and can be quite low-level. -They are mostly useful for building blocks for higher-level types. - -Timezone-aware `DateTime` and `Date` types have two methods returning naive versions: -[`naive_local`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.naive_local) returns -a view to the naive local time, -and [`naive_utc`](https://docs.rs/chrono/0.4/chrono/struct.DateTime.html#method.naive_utc) returns -a view to the naive UTC time. - ## Limitations Only proleptic Gregorian calendar (i.e. extended to support older dates) is supported. @@ -408,7 +49,7 @@ if you want. Chrono inherently does not support an inaccurate or partial date and time representation. Any operation that can be ambiguous will return `None` in such cases. For example, "a month later" of 2014-01-30 is not well-defined -and consequently `Utc.ymd(2014, 1, 30).with_month(2)` returns `None`. +and consequently `Utc.ymd_opt(2014, 1, 30).unwrap().with_month(2)` returns `None`. Non ISO week handling is not yet supported. For now you can use the [chrono_ext](https://crates.io/crates/chrono_ext) @@ -416,4 +57,3 @@ crate ([sources](https://github.com/bcourtine/chrono-ext/)). Advanced time zone handling is not yet supported. For now you can try the [Chrono-tz](https://github.com/chronotope/chrono-tz/) crate instead. - |