Stdlib: Locale::lookup()/locale_lookup() + acceptFromHttp — BCP-47 negotiate missing (ext/intl/locale)

[PurHur]

Category

stdlib · php-src-strict · child of #3336 / extends Locale surface (#6696)

Problem

Locale OOP today covers getDefault/setDefault/getPrimaryLanguage/getRegion/getScript/getDisplayName. Negotiating Accept-Language / preferred locale lists still missing:

API	Role
Locale::lookup() / locale_lookup()	Best match from locale list vs locale
Locale::filterMatches() / locale_filter_matches()	Filter match predicate
Locale::acceptFromHttp() / locale_accept_from_http()	Parse HTTP Accept-Language

Check	Zend + intl	VM (forced Locale)
method_exists('Locale','lookup')	true	false ❌
Locale::lookup(['de-DE','fr-FR'], 'de-CH', false, 'en_US')	de_DE (or equiv)	n/a

php-src reference

• php/php-src ext/intl/locale/locale_methods.c — locale_lookup, locale_filter_matches, locale_accept_from_http
• ICU: uloc_acceptLanguage / related (v1 may use PHP BCP-47 matching without full ICU)

PHP implementation target

• ext/intl/VmLocale.php — lookup / filterMatches / acceptFromHttp
• Procedural wrappers + Locale static methods in BuiltinClasses
• Gated with IntlExtensionPolicy::advertisesLocale() (Regression: Locale/NumberFormatter/IntlDateFormatter/IntlCalendar/IntlTimeZone + locale_get_default without ext/intl (re-#16214, ext/intl/php_intl.c) #19670)

Repro

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh && php bin/vm.php -r "
var_export(function_exists(\"locale_lookup\"));
"'

Done when

• Locale::lookup(['de_DE','fr_FR'], 'de_CH', false, 'en_US') returns German match (php-src-strict shape)
• Locale::acceptFromHttp('en-US,en;q=0.9,fr;q=0.8') non-empty preferred tag
• locale_filter_matches true/false parity on simple lang/region pairs
• Phantom-withheld without intl
• ./script/phpunit.sh --filter LocaleLookup green
• php-src-strict

Related

• Stdlib: ext/intl — IntlDateFormatter / NumberFormatter / locale formatting (ext/intl parity) #3336 · Stdlib: Locale class — getDefault()/getDisplayName() ICU locale API missing (ext/intl/locale) #6696 Locale parsers · Stdlib: locale_get_default()/locale_set_default() and Locale class missing (ext/intl/php_intl.c) #9576 get/setDefault

[PurHur]

claim: PHP Compiler STD Lib Advanced — batch (#20035, #20036, #20037). Queued after #20035 merge.

[PurHur]

claim: PHP Compiler STD Lib Advanced — starting #20036 after #20035 merged (#20040).

[PurHur]

Merged: #20042

Verification

• php test/repro/issue_20036_locale_lookup.php → lookup=de-DE; fallback=en_US; filter=1; accept=en_US
• vendor/bin/phpunit --filter VmLocaleLookupTest → OK (3 tests)

Next: verify-close #3339 posix; SoapClient v1 (#20037) queued.