Localize version 0.37.0

[0.37.0] — May 17th, 2026

Bug Fixes

• Localize.DateTime.Formatter audit: removed remaining :gregorian / Calendar.ISO hardcoding. The {0} / {1} date-time placeholders now derive the CLDR calendar from the date instead of always asking for the gregorian pattern, ISO week-of-year (w / Y) prefers the date's own iso_week_of_year/3 callback before falling back to converting to Calendar.ISO, and iso_day/1's dead silent-fallback clause for unknown calendars was removed.

• Localize.Date.to_string/2 now honours CLDR number_system overrides carried alongside date patterns — Hebrew dates render in Hebrew numerals (י״ב באייר ה׳תשפ״ד), Japanese imperial year-1 renders as 元年, and numeric overrides like :arab transliterate per-field via the system's digit set. Algorithmic systems resolve through CLDR's numberingSystems.json to the right RBNF rule (:hebr → :hebrew, :jpanyear → :spellout-numbering-year-latn under :ja).

• Localize.Date.to_string/2 with a skeleton format (e.g. :yMMMM) against a non-Gregorian calendar no longer infinite-loops. Match.best_match/3 now receives the calendar explicitly and resolve_skeleton carries a seen set, terminating any residual match cycle.

• Localize.Date.to_string/2 now honours non-Gregorian calendars carried in the date's :calendar field — previously every call hard-coded :gregorian. A Date built with Calendrical.Japanese now formats as 平成12年1月1日 under :"ja-JP" instead of 2000/01/01.

• Localize.Calendar.localize/3 for :era now derives the correct era by delegating to the date's year_of_era/3 callback. Previously it always returned era 1, producing 白雉 (Hakuchi, AD 650) for every Calendrical.Japanese date.

• Localize.DateTime.Formatter y token now uses the calendar's calendar_year/3 (or year_of_era/3 as fallback) for non-Calendar.ISO dates, so era-relative year numbering — Heisei 12, Reiwa 6, AH 1420, BE 2543 — renders correctly.

• Localize.DateTime.Format.resolve_variant/2 now handles the CLDR %{format: pattern, number_system: ns} variant shape. Without this, locales whose date patterns carry a number_system override (Japanese jpanyear, Hebrew hebr) silently fell back to Gregorian.