time 0.3.47

Date and time library. Fully interoperable with the standard library. Mostly compatible with #![no_std].
Documentation
#[rustfmt::skip] // Tries to remove the leading `::`, which breaks compilation.
use ::serde::{Deserialize, Serialize};
use serde_test::{
    assert_de_tokens, assert_de_tokens_error, assert_ser_tokens_error, assert_tokens, Configure,
    Token,
};
use time::format_description::well_known::{iso8601, Iso8601};
use time::format_description::BorrowedFormatItem;
use time::macros::{date, datetime, offset, time};
use time::{serde, Date, OffsetDateTime, PrimitiveDateTime, Time, UtcOffset};

// Not used in the tests, but ensures that the macro compiles.
#[expect(dead_code)]
const ISO_FORMAT: Iso8601<{ iso8601::Config::DEFAULT.encode() }> =
    Iso8601::<{ iso8601::Config::DEFAULT.encode() }>;
time::serde::format_description!(my_format, OffsetDateTime, ISO_FORMAT);
time::serde::format_description!(
    my_format2,
    OffsetDateTime,
    Iso8601::<{ iso8601::Config::DEFAULT.encode() }>
);

mod nested {
    time::serde::format_description!(
        pub(super) offset_dt_format,
        OffsetDateTime,
        "custom format: [year]-[month]-[day] [hour]:[minute]:[second] [offset_hour \
         sign:mandatory]:[offset_minute]"
    );
    time::serde::format_description!(
        pub primitive_dt_format,
        PrimitiveDateTime,
        "custom format: [year]-[month]-[day] [hour]:[minute]:[second]"
    );
    time::serde::format_description!(
        pub(in crate::serde::macros) time_format,
        Time,
        "custom format: [minute]:[second]"
    );
}
serde::format_description!(date_format, Date, "custom format: [year]-[month]-[day]");
serde::format_description!(
    offset_format,
    UtcOffset,
    "custom format: [offset_hour sign:mandatory]:[offset_minute]"
);

const TIME_FORMAT_ALT: &[BorrowedFormatItem<'_>] =
    time::macros::format_description!("[hour]:[minute]");
serde::format_description!(time_format_alt, Time, TIME_FORMAT_ALT);
serde::format_description!(
    time_format_alt2,
    Time,
    time::macros::format_description!("[hour]:[minute]")
);

#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
struct TestCustomFormat {
    #[serde(with = "nested::offset_dt_format")]
    offset_dt: OffsetDateTime,
    #[serde(with = "nested::primitive_dt_format::option")]
    primitive_dt: Option<PrimitiveDateTime>,
    #[serde(with = "date_format")]
    date: Date,
    #[serde(with = "nested::time_format::option")]
    time: Option<Time>,
    #[serde(with = "offset_format")]
    offset: UtcOffset,
    #[serde(with = "time_format_alt")]
    time_alt: Time,
}

#[test]
fn custom_serialize() {
    let value = TestCustomFormat {
        offset_dt: datetime!(2000-01-01 00:00 -4:00),
        primitive_dt: Some(datetime!(2000-01-01 00:00)),
        date: date!(2000-01-01),
        time: None,
        offset: offset!(-4),
        time_alt: time!(12:34),
    };
    assert_tokens(
        &value.compact(),
        &[
            Token::Struct {
                name: "TestCustomFormat",
                len: 6,
            },
            Token::Str("offset_dt"),
            Token::BorrowedStr("custom format: 2000-01-01 00:00:00 -04:00"),
            Token::Str("primitive_dt"),
            Token::Some,
            Token::BorrowedStr("custom format: 2000-01-01 00:00:00"),
            Token::Str("date"),
            Token::BorrowedStr("custom format: 2000-01-01"),
            Token::Str("time"),
            Token::None,
            Token::Str("offset"),
            Token::BorrowedStr("custom format: -04:00"),
            Token::Str("time_alt"),
            Token::BorrowedStr("12:34"),
            Token::StructEnd,
        ],
    );
}

#[test]
fn custom_serialize_error() {
    // Deserialization error due to parse problem.
    assert_de_tokens_error::<TestCustomFormat>(
        &[
            Token::Struct {
                name: "TestCustomFormat",
                len: 5,
            },
            Token::Str("offset_dt"),
            Token::BorrowedStr("custom format: 2000-01-01 0:00:00 -04:00"),
        ],
        "the 'hour' component could not be parsed",
    );
    // Parse problem in optional field.
    assert_de_tokens_error::<TestCustomFormat>(
        &[
            Token::Struct {
                name: "TestCustomFormat",
                len: 5,
            },
            Token::Str("offset_dt"),
            Token::BorrowedStr("custom format: 2000-01-01 00:00:00 -04:00"),
            Token::Str("primitive_dt"),
            Token::Some,
            Token::BorrowedStr("custom format: 2000-01-01 0:00:00 -04:00"),
        ],
        "the 'hour' component could not be parsed",
    );
    // Type error
    assert_de_tokens_error::<TestCustomFormat>(
        &[
            Token::Struct {
                name: "TestCustomFormat",
                len: 5,
            },
            Token::Str("offset_dt"),
            Token::Bool(false),
        ],
        "invalid type: boolean `false`, expected a(n) `OffsetDateTime` in the format \"custom \
         format: [year]-[month]-[day] [hour]:[minute]:[second] [offset_hour \
         sign:mandatory]:[offset_minute]\"",
    );
    assert_de_tokens_error::<TestCustomFormat>(
        &[
            Token::Struct {
                name: "TestCustomFormat",
                len: 5,
            },
            Token::Str("offset_dt"),
            Token::BorrowedStr("custom format: 2000-01-01 00:00:00 -04:00"),
            Token::Str("primitive_dt"),
            Token::Bool(false),
        ],
        "invalid type: boolean `false`, expected an `Option<PrimitiveDateTime>` in the format \
         \"custom format: [year]-[month]-[day] [hour]:[minute]:[second]\"",
    );
}

// This format string has offset_hour and offset_minute, but is for formatting PrimitiveDateTime.
serde::format_description!(
    primitive_date_time_format_bad,
    PrimitiveDateTime,
    "[offset_hour]:[offset_minute]"
);

#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
struct TestCustomFormatPrimitiveDateTimeBad {
    #[serde(with = "primitive_date_time_format_bad")]
    dt: PrimitiveDateTime,
}

#[test]
fn custom_serialize_bad_type_error() {
    let value = TestCustomFormatPrimitiveDateTimeBad {
        dt: datetime!(2000-01-01 00:00),
    };

    assert_ser_tokens_error::<TestCustomFormatPrimitiveDateTimeBad>(
        &value,
        &[
            Token::Struct {
                name: "TestCustomFormatPrimitiveDateTimeBad",
                len: 1,
            },
            Token::Str("dt"),
        ],
        "The type being formatted does not contain sufficient information to format a component.",
    );
}

// Test the behavior of versioning.
serde::format_description!(version = 1, version_test_1, Time, "[[ [hour]:[minute]");
serde::format_description!(version = 1, version_test_2, Time, r"\\ [hour]:[minute]");
serde::format_description!(version = 2, version_test_3, Time, r"\\ [hour]:[minute]");
serde::format_description!(version, Time, "[hour]:[minute]");

#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
struct TestVersioning {
    #[serde(with = "version_test_1")]
    time_1: Time,
    #[serde(with = "version_test_2")]
    time_2: Time,
    #[serde(with = "version_test_3")]
    time_3: Time,
    #[serde(with = "version")]
    time_4: Time,
}

#[test]
fn versioning() {
    let value = TestVersioning {
        time_1: Time::MIDNIGHT,
        time_2: Time::MIDNIGHT,
        time_3: Time::MIDNIGHT,
        time_4: Time::MIDNIGHT,
    };
    assert_tokens(
        &value,
        &[
            Token::Struct {
                name: "TestVersioning",
                len: 4,
            },
            Token::Str("time_1"),
            Token::Str("[ 00:00"),
            Token::Str("time_2"),
            Token::Str(r"\\ 00:00"),
            Token::Str("time_3"),
            Token::Str(r"\ 00:00"),
            Token::Str("time_4"),
            Token::Str("00:00"),
            Token::StructEnd,
        ],
    );
}

serde::format_description!(
    version = 1,
    nested_v1,
    Time,
    "[hour]:[minute][optional [:[second]]]"
);
serde::format_description!(
    version = 2,
    nested_v2,
    Time,
    "[hour]:[minute][optional [:[second]]]"
);

#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
struct TestNested {
    #[serde(with = "nested_v1")]
    time_1: Time,
    #[serde(with = "nested_v2")]
    time_2: Time,
}

#[test]
fn nested() {
    let value = TestNested {
        time_1: time!(12:34:56),
        time_2: time!(12:34:56),
    };
    assert_tokens(
        &value,
        &[
            Token::Struct {
                name: "TestNested",
                len: 2,
            },
            Token::Str("time_1"),
            Token::Str("12:34:56"),
            Token::Str("time_2"),
            Token::Str("12:34:56"),
            Token::StructEnd,
        ],
    );

    let expected = TestNested {
        time_1: time!(12:34),
        time_2: time!(12:34),
    };
    assert_de_tokens(
        &expected,
        &[
            Token::Struct {
                name: "TestNested",
                len: 2,
            },
            Token::Str("time_1"),
            Token::Str("12:34"),
            Token::Str("time_2"),
            Token::Str("12:34"),
            Token::StructEnd,
        ],
    );
}