Localize version 0.40.0

[0.40.0] — June 1st, 2026

Breaking Changes

• A bare relative :locale_cache_dir (no :otp_app set) is now refused at app start with Localize.LocaleCacheDirError — it resolved against the BEAM's CWD, which differs between mix tasks, mix test, and a release. Fix: add :otp_app to anchor the relative path, or use an absolute path.

Bug Fixes

• Localize.Locale.Provider.locale_cache_dir/0 validates its configuration at app start (via Localize.Supervisor) and raises Localize.LocaleCacheDirError instead of silently reading from the wrong directory at runtime.

• Localize.Locale.LocaleDisplay.display_name/2 no longer raises FunctionClauseError on a BCP 47 generic extension carrying an odd number of subtags (e.g. cr-s-7b); the trailing singleton chunk now renders as a bare subtag.

Enhancements

• New :otp_app config key. Three supported forms for the locale cache directory: (1) :otp_app only → Application.app_dir(<otp_app>, "priv/localize/locales"); (2) :otp_app + relative :locale_cache_dir → Application.app_dir(<otp_app>, <relative>); (3) absolute :locale_cache_dir → used verbatim, :otp_app ignored.