fix(intl): apply locale and timezone data

[proggeramlug]

Fixes #8903

Summary

• resolve and validate named DateTimeFormat zones with the compiled IANA database, including DST
• route weekday-only component formats through the correct ICU date fieldset
• retain Unicode normalization in auto-optimized Collator builds
• add a Node-parity regression covering de-DE date, weekday, Berlin time, and collation

Testing

Run on root@perrymaster.skelpo.net:

• cargo test --release -p perry-runtime name_bearing_components_match_node -- --nocapture
• cargo test --release -p perry-runtime compiled_tzdb_resolves_named_zone_and_dst -- --nocapture
• cargo test --release -p perry string_normalization_gate_covers_normalize_and_locale_compare -- --nocapture
• compiled and ran test_gap_issue_8903_intl_locale_data.ts with Node 26.8.1, full PERRY_NO_AUTO_OPTIMIZE=1, and auto-optimized Perry; all outputs were byte-identical

No version bump.

Summary by CodeRabbit

• Bug Fixes

  • Intl.DateTimeFormat now supports named IANA time zones with accurate daylight-saving transitions.
  • Weekday-only date formats now use the requested locale’s language data.
  • Intl.Collator preserves locale-aware comparison and Unicode normalization in optimized builds.
  • Regular expression behavior is preserved for application-created expressions in compiled packages.

• Performance

  • Array subclass push() operations can use a faster inline path when applicable.

• Tests

  • Added coverage for German localization, Berlin time-zone formatting, daylight saving, and collation behavior.

[coderabbitai]

Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 8e3b8d52-e0e9-49aa-b59a-e46e8e4f55a1

📥 Commits

Reviewing files that changed from the base of the PR and between d4ec70c and 5bc2ef4.

📒 Files selected for processing (12)

• changelog.d/8995-compiled-package-regexp.md
• changelog.d/8996-elements-inline-push.md
• changelog.d/8997-intl-locale-timezone.md
• crates/perry-runtime/Cargo.toml
• crates/perry-runtime/src/date.rs
• crates/perry-runtime/src/intl.rs
• crates/perry-runtime/src/intl/date_collator.rs
• crates/perry-runtime/src/intl/icu_dtf.rs
• crates/perry-runtime/src/intl/time_zone.rs
• crates/perry/src/commands/compile/collect_modules/feature_detect.rs
• crates/perry/src/commands/compile/types.rs
• test-files/test_gap_issue_8903_intl_locale_data.ts

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📝 Walkthrough

Walkthrough

The runtime adds compiled IANA timezone resolution, localized weekday formatting, and separate date/time formatter paths. Compiler detection enables normalization data for Intl.Collator. Changelog entries document these fixes and two additional compiled-runtime changes.

Changes

Intl locale and timezone behavior

Layer / File(s)	Summary
Compiled timezone resolution crates/perry-runtime/Cargo.toml, crates/perry-runtime/src/date.rs, crates/perry-runtime/src/intl/time_zone.rs, crates/perry-runtime/src/intl.rs	The runtime adds a compiled IANA database provider, canonicalizes named zones, and computes DST-aware offsets. Minimal builds retain structural timezone validation.
Localized DateTimeFormat field formatting crates/perry-runtime/src/intl/icu_dtf.rs, crates/perry-runtime/src/intl/date_collator.rs, test-files/test_gap_issue_8903_intl_locale_data.ts, changelog.d/8997-intl-locale-timezone.md	DateTimeFormat selects separate date, time, or combined formatters. Weekday-only requests use localized ICU data. Regression coverage verifies German locale, Berlin timezone, weekday, and collation output.
Collator normalization feature detection crates/perry/src/commands/compile/collect_modules/feature_detect.rs, crates/perry/src/commands/compile/types.rs	Intl.Collator now enables the string-normalization feature gate. Comments and tests describe and verify the additional trigger.

Additional release notes

Layer / File(s)	Summary
Compiled runtime changelog entries changelog.d/8995-compiled-package-regexp.md, changelog.d/8996-elements-inline-push.md	The changelog documents preserved RegExp behavior in compiled packages and inline push handling for Array subclasses.

Estimated code review effort: 3 (Moderate) | ~25 minutes

Sequence Diagram(s)

sequenceDiagram
  participant Application
  participant IntlDateTimeFormat
  participant TimeZoneResolver
  participant CompiledTzdb
  participant ICUFormatter
  Application->>IntlDateTimeFormat: format date with locale and named timeZone
  IntlDateTimeFormat->>TimeZoneResolver: canonicalize named timezone
  TimeZoneResolver->>CompiledTzdb: resolve zone and instant offset
  CompiledTzdb-->>TimeZoneResolver: canonical zone and DST-aware offset
  IntlDateTimeFormat->>ICUFormatter: format selected date/time fields
  ICUFormatter-->>IntlDateTimeFormat: localized output
  IntlDateTimeFormat-->>Application: formatted string

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Suggested reviewers: thehypnoo

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[proggeramlug]

Merged (batched with #8995 and #8996).

I checked the timezone work behaviourally rather than trusting the unit tests, since "resolve named zones from the compiled IANA database, including DST" is the sort of claim that passes a fixed-offset implementation right up until it does not:

America/New_York, 2026-07-15T12:00Z   perry=08:00   node=08:00
Asia/Tokyo,       2026-07-15T12:00Z   perry=21:00   node=21:00

08:00 is the one that matters — that is EDT, so the offset is genuinely coming from DST rules rather than a stored standard offset, which a July date would otherwise render as 07:00.

One fix pushed: the fragment was named 8903-intl-locale-timezone.md. #8903 is the issue this fixes, not the PR, so the change would have been filed under an issue number at release time. Renamed to 8997-.

Validation — runtime 2787/0, codegen 1341/0, stdlib 124/0 (RUST_TEST_THREADS=1); scripts/run_lint_gates.sh 57 of 58 with the compile tier green — the exception is the pre-existing Actions-expression artifact (#8929).