jiff-tzdb

This release relaxes Jiff's dependency on windows-sys to include multiple semver incompatible releases. The purpose of this relaxation is to enable Jiff to work with different versions of windows-sys in the hopes that this reduces the likelihood that multiple copies of windows-sys are included in your dependency tree.

Dependencies:

• #106: Relax windows-sys dependency constraint to >=0.52.0, <=0.59.*.

This release includes a new top-level type, SignedDuration, that provides a near exact replica of std::time::Duration, but signed. It is meant to provide alternative APIs for working with durations at a lower level than what Span provides, and to facilitate better integration with the standard library.

A SignedDuration has also been integrated with all of Jiff's datetime types. For example, previously, Zoned::checked_add only accepted a concrete jiff::Span. But now it accepts a jiff::Span, jiff::SignedDuration or even a std::time::Duration. Moreover, all of the until and since APIs on datetime types have been ported and copied to return SignedDuration under the duration_until and duration_since names.

This marks an initial integration phase with SignedDuration. It is planned to integrate it more with the datetime types. Currently, there are integrations on Timestamp and Span, but more will be added in the future.

Overall, folks should still use Span. That is the intended default duration type in Jiff and will continue to be. Users of Jiff may find SignedDuration useful in contexts where speed is important or when one needs to integrate with the standard library.

This release also includes a few related deprecations as the APIs involving std::time::Duration are phased out in favor of SignedDuration.

Deprecations:

• Timestamp::as_duration: replaced with as_jiff_duration, which will be renamed to as_duration in jiff 0.2.
• Timestamp::from_duration: replaced with from_jiff_duration, which will be renamed to from_duration in jiff 0.2.
• Timestamp::from_signed_duration: replaced with from_jiff_duration.
• Span::to_duration: replaced with to_jiff_duration, which will be renamed to to_duration in jiff 0.2.

Basically, all of the above APIs either accept or return a std::time::Duration. To avoid breaking changes at this point, new methods for SignedDuration were added. For example, Timestamp::as_jiff_duration. In jiff 0.2, the above deprecated methods will be removed and replaced with equivalent methods that accept or return a SignedDuration instead. Callers can then convert between a SignedDuration and a std::time::Duration using appropriate TryFrom trait implementations.

Enhancements:

• #21: Add new top-level SignedDuration type.
• #90: Improve error message when using Span with >=day units with a Timestamp.

Performance:

• #104 Optimize offset calculations in time zones without DST.
• #105 Optimize offset calculations for timestamps after last DST rule change.

This release includes some improvements and bug fixes, particularly for Jiff's strtime APIs.

Enhancements:

• #63: Add link to original Chrono maintainer's commentary in DESIGN.md.
• #75: Add support for %V for formatting and parsing IANA time zone identifiers.
• #79: Add devcontainer.json to support GitHub Codespaces.
• #85: Set correct ranges for internal tracking in return value of days_in_month.

Bug fixes:

• #59: Fixes a bug where some Spans could not be roundtripped through ISO 8601.
• #71: Tweak wording in documentation of "printf"-style API.
• #73: Make it so %.Nf only formats to N decimal places.
• #77: Disable optimizations when running tests.

This release includes a small improvement for strptime that permits %Y%m%d to parse 20240730 correctly.

Enhancements:

• #62: Tweak strptime so that things like %Y aren't unceremoniously greedy.

This release features support for wasm32-unknown-unknown. That is, when Jiff's new js crate feature is enabled, Jiff will automatically use JavaScript APIs to determine the current time and time zone.

Enhancements:

• #58: Add WASM support and a new PLATFORM.md guide.

This release features a few new APIs that a need for arose while experimenting with actually using Jiff in real projects. Namely, the jiff::fmt::strtime module now has %f and %.f directives for parsing and formatting fractional seconds. And both jiff::fmt::rfc2822 and jiff::fmt::strtime now have support for skipping weekday checks during parsing. (Previously, Jiff required that an English weekday be consistent with the date parsed, and there was no way to opt out. While this is still the default behavior, callers can disable this check.)

Enhancements:

• #52: Improve documentation for Span getter methods.
• #53: Add support for skipping weekday checking when parsing datetimes.
• #55: Add support for fractional seconds in jiff::fmt::strtime.

Bug fixes:

• #49: Fix informational regex describing ISO 8601 format.
• #51: Explicitly allow new deny-by-default lint ambiguous_negative_literals.

This is a new semver compatible release. The principle addition are APIs for converting between a jiff::Span and a std::time::Duration. Specifically, there are now TryFrom<Span> for Duration and TryFrom<Duration> for Span trait implementations. There is also a Span::to_duration, which requires a relative date, for converting spans with non-uniform units (like months) to a Duration.

Enhancements:

• #21, #40: Adds APIs for converting between Span and std::time::Duration.

Bug fixes:

• #36: Saturating arithmetic for Timestamp panics with day-or-greater units.
• #38: Fix some bugs in the micro-benchmarks.
• #39: Document that the RFC 2822 parser is not technically fully spec compliant.

The initial release of Jiff.