Regression: IntlTimeZone::createTimeZone unknown ID returns GMT/UTC — Zend Etc/Unknown (ext/intl/timezone)

[PurHur]

Category

stdlib · php-src-strict · intl timezone

Problem

IntlTimeZone::createTimeZone($id) for an unrecognized zone does not match Zend/php-src:

1. Unknown ID (e.g. No/Such) — Zend returns an IntlTimeZone whose getID() is Etc/Unknown; VM returns GMT.
2. Empty string '' — Zend → Etc/Unknown; VM → default TZ (UTC on this host).

VmIntlTimeZone::resolveTimezoneId() currently documents “unknown IDs become GMT”, but that does not match Zend 8.2 / current php-src ICU sentinel behavior (TimeZone::getUnknown() → Etc/Unknown).

Verified 2026-07-30 (host Zend 8.2.32 vs bin/vm.php on master):

Repro	Zend 8.2 getID()	VM getID()
IntlTimeZone::createTimeZone('No/Such')	Etc/Unknown	GMT
IntlTimeZone::createTimeZone('')	Etc/Unknown	UTC (default TZ)
IntlTimeZone::createTimeZone('America/New_York')->getID()	America/New_York	America/New_York (ok)

php-src reference

• php/php-src ext/intl/timezone/timezone_methods.cpp — intltz_create_time_zone / ICU TimeZone::createTimeZone
• ICU unknown zone → TimeZone::getUnknown() → ID Etc/Unknown (also IntlTimeZone::getUnknown(), Stdlib: IntlTimeZone::getUnknown()/getUTC()/createEnumeration()/getIDForWindowsID() missing after #20769 (ext/intl/timezone) #20852)

PHP implementation target

• ext/intl/VmIntlTimeZone.php — resolveTimezoneId() / createTimeZone path: map empty + unknown IDs to Etc/Unknown (same object shape as getUnknown()), not GMT / defaultTimezoneGet()
• Align any intl error code/message with php-src for the unknown-ID case
• Prefer PHP-in-PHP; no new runtime/*.c

Repro

./script/docker-exec.sh -- bash -lc 'php -r '\''
$z = IntlTimeZone::createTimeZone("No/Such");
echo $z->getID(), "\n";
$e = IntlTimeZone::createTimeZone("");
echo $e->getID(), "\n";
'\'' && php bin/vm.php -r '\''
$z = IntlTimeZone::createTimeZone("No/Such");
echo $z->getID(), "\n";
$e = IntlTimeZone::createTimeZone("");
echo $e->getID(), "\n";
'\'''

Done when

• Unknown / empty ID → getID() === 'Etc/Unknown' on VM (and JIT/AOT if in scope)
• Valid IDs unchanged
• Compliance .phpt under test/compliance/cases/ for intl timezone
• php-src-strict; no php-compiler-strict shortcut

[PurHur]

Trust probe (before claim)

Gate	Status	Note
docker info	green	host
bootstrap-inventory --check	red (doc drift)	Stale docs/bootstrap-inventory.md — construct warnings 21388→21397 (VmPDOStatement / InheritanceVariance / StringSscanfArray); not a link failure
release-readiness --json	running	will update when finished

claim: PHP Compiler Ext — I/O & Crypto — starting this run on #25356 (IntlTimeZone::createTimeZone unknown/empty → Etc/Unknown).

[PurHur]

Trust probe (update)

Gate	Status	Note
bootstrap-inventory	green	OK 6639/6639
north-star5-fast	green	via release-readiness
vm-driver-probe	green
spine-coverage	green
helper-runtime-prelink	red	core_fingerprint mismatch (#24302) — pre-existing on master
cold-build	red	timeout 121s (#24302/#24351) — pre-existing
user_release_ready	no	first fails: helper-runtime-prelink, cold-build

Pillar 1 reds are pre-existing release-path debt (#24302), not link/inventory. Proceeding with #25356 (createTimeZone → Etc/Unknown).

[PurHur]

Merged via #25676 (9999b2a16).

Verification

• Zend + VM: createTimeZone('No/Such') / '' → Etc/Unknown, intl_get_error_code()=0
• php vendor/bin/phpunit --filter intltimezone_create_unknown_25356 → OK (2 tests, VM+JIT) on host with php-intl
• Sibling intltimezone_offset_display still OK
• Docker image without php-intl SKIPIFs (unchanged policy Regression: Locale/NumberFormatter/IntlDateFormatter/IntlCalendar/IntlTimeZone + locale_get_default without ext/intl (re-#16214, ext/intl/php_intl.c) #19670)

Fix

VmIntlTimeZone::resolveTimezoneId() — empty/unknown → Etc/Unknown (php-src ICU TimeZone::getUnknown()), not GMT/default TZ.