feature #31292 [Validator] Allow intl timezones (ro0NL)

This PR was merged into the 4.3-dev branch.

Discussion
----------

[Validator] Allow intl timezones

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | no
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | ref #28836
| License       | MIT
| Doc PR        | symfony/symfony-docs#11502

This PR considers the ICU timezones (#28831) as valid, as well as the PHP ones.

Both can be used in `DateTimeZone`, but expired timezones cannot be used with `IntlTimeZone`. The `intlCompatibility` option ensures compatibility between both.

Practically this allows for both `UTC` and `Etc/UTC`, where the latter should be preferred. I.e. currently `Etc/UTC` is considered an invalid timezone ... which it's not.

Commits
-------

7294b59 [Validator] Allow intl timezones

src/Symfony/Component/Validator/Constraints/Timezone.php

@@ -26,15 +26,18 @@ class Timezone extends Constraint
     public const TIMEZONE_IDENTIFIER_ERROR = '5ce113e6-5e64-4ea2-90fe-d2233956db13';
     public const TIMEZONE_IDENTIFIER_IN_ZONE_ERROR = 'b57767b1-36c0-40ac-a3d7-629420c775b8';
     public const TIMEZONE_IDENTIFIER_IN_COUNTRY_ERROR = 'c4a22222-dc92-4fc0-abb0-d95b268c7d0b';
+    public const TIMEZONE_IDENTIFIER_INTL_ERROR = '45863c26-88dc-41ba-bf53-c73bd1f7e90d';
 
     public $zone = \DateTimeZone::ALL;
     public $countryCode;
+    public $intlCompatible = false;
     public $message = 'This value is not a valid timezone.';
 
     protected static $errorNames = [
         self::TIMEZONE_IDENTIFIER_ERROR => 'TIMEZONE_IDENTIFIER_ERROR',
         self::TIMEZONE_IDENTIFIER_IN_ZONE_ERROR => 'TIMEZONE_IDENTIFIER_IN_ZONE_ERROR',
         self::TIMEZONE_IDENTIFIER_IN_COUNTRY_ERROR => 'TIMEZONE_IDENTIFIER_IN_COUNTRY_ERROR',
+        self::TIMEZONE_IDENTIFIER_INTL_ERROR => 'TIMEZONE_IDENTIFIER_INTL_ERROR',
     ];
 
     /**
@@ -51,5 +54,8 @@ public function __construct(array $options = null)
         } elseif (\DateTimeZone::PER_COUNTRY !== (\DateTimeZone::PER_COUNTRY & $this->zone)) {
             throw new ConstraintDefinitionException('The option "countryCode" can only be used when the "zone" option is configured with "\DateTimeZone::PER_COUNTRY".');
         }
+        if ($this->intlCompatible && !class_exists(\IntlTimeZone::class)) {
+            throw new ConstraintDefinitionException('The option "intlCompatible" can only be used when the PHP intl extension is available.');
+        }
     }
 }

src/Symfony/Component/Validator/Constraints/TimezoneValidator.php

@@ -11,6 +11,8 @@
 
 namespace Symfony\Component\Validator\Constraints;
 
+use Symfony\Component\Intl\Exception\MissingResourceException;
+use Symfony\Component\Intl\Timezones;
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\ConstraintValidator;
 use Symfony\Component\Validator\Exception\UnexpectedTypeException;
@@ -43,14 +45,28 @@ public function validate($value, Constraint $constraint)
 
         $value = (string) $value;
 
-        // @see: https://bugs.php.net/bug.php?id=75928
+        if ($constraint->intlCompatible && 'Etc/Unknown' === \IntlTimeZone::createTimeZone($value)->getID()) {
+            $this->context->buildViolation($constraint->message)
+                ->setParameter('{{ value }}', $this->formatValue($value))
+                ->setCode(Timezone::TIMEZONE_IDENTIFIER_INTL_ERROR)
+                ->addViolation();
+
+            return;
+        }
+
         if ($constraint->countryCode) {
-            $timezoneIds = @\DateTimeZone::listIdentifiers($constraint->zone, $constraint->countryCode) ?: [];
+            $phpTimezoneIds = @\DateTimeZone::listIdentifiers($constraint->zone, $constraint->countryCode) ?: [];
+            try {
+                $intlTimezoneIds = Timezones::forCountryCode($constraint->countryCode);
+            } catch (MissingResourceException $e) {
+                $intlTimezoneIds = [];
+            }
         } else {
-            $timezoneIds = \DateTimeZone::listIdentifiers($constraint->zone);
+            $phpTimezoneIds = \DateTimeZone::listIdentifiers($constraint->zone);
+            $intlTimezoneIds = self::getIntlTimezones($constraint->zone);
         }
 
-        if (\in_array($value, $timezoneIds, true)) {
+        if (\in_array($value, $phpTimezoneIds, true) || \in_array($value, $intlTimezoneIds, true)) {
             return;
         }
 
@@ -63,9 +79,9 @@ public function validate($value, Constraint $constraint)
         }
 
         $this->context->buildViolation($constraint->message)
-                      ->setParameter('{{ value }}', $this->formatValue($value))
-                      ->setCode($code)
-                      ->addViolation();
+              ->setParameter('{{ value }}', $this->formatValue($value))
+              ->setCode($code)
+              ->addViolation();
     }
 
     /**
@@ -89,4 +105,26 @@ protected function formatValue($value, $format = 0)
 
         return array_search($value, (new \ReflectionClass(\DateTimeZone::class))->getConstants(), true) ?: $value;
     }
+
+    private static function getIntlTimezones(int $zone): array
+    {
+        $timezones = Timezones::getIds();
+
+        if (\DateTimeZone::ALL === (\DateTimeZone::ALL & $zone)) {
+            return $timezones;
+        }
+
+        $filtered = [];
+        foreach ((new \ReflectionClass(\DateTimeZone::class))->getConstants() as $const => $flag) {
+            if ($flag !== ($flag & $zone)) {
+                continue;
+            }
+
+            $filtered[] = array_filter($timezones, static function ($id) use ($const) {
+                return 0 === stripos($id, $const.'/');
+            });
+        }
+
+        return $filtered ? array_merge(...$filtered) : [];
+    }
 }

src/Symfony/Component/Validator/Tests/Constraints/TimezoneValidatorTest.php

@@ -60,7 +60,26 @@ public function testValidTimezones(string $timezone)
 
     public function getValidTimezones(): iterable
     {
+        // ICU standard (alias/BC in PHP)
+        yield ['Etc/UTC'];
+        yield ['Etc/GMT'];
+        yield ['America/Buenos_Aires'];
+
+        // PHP standard (alias in ICU)
+        yield ['UTC'];
         yield ['America/Argentina/Buenos_Aires'];
+
+        // not deprecated in ICU
+        yield ['CST6CDT'];
+        yield ['EST5EDT'];
+        yield ['MST7MDT'];
+        yield ['PST8PDT'];
+        yield ['America/Montreal'];
+
+        // expired in ICU
+        yield ['Europe/Saratov'];
+
+        // standard
         yield ['America/Barbados'];
         yield ['America/Toronto'];
         yield ['Antarctica/Syowa'];
@@ -71,7 +90,6 @@ public function getValidTimezones(): iterable
         yield ['Europe/Copenhagen'];
         yield ['Europe/Paris'];
         yield ['Pacific/Noumea'];
-        yield ['UTC'];
     }
 
     /**
@@ -90,6 +108,8 @@ public function testValidGroupedTimezones(string $timezone, int $zone)
 
     public function getValidGroupedTimezones(): iterable
     {
+        yield ['America/Buenos_Aires', \DateTimeZone::AMERICA | \DateTimeZone::AUSTRALIA]; // icu
+        yield ['America/Argentina/Buenos_Aires', \DateTimeZone::AMERICA]; // php
         yield ['America/Argentina/Cordoba', \DateTimeZone::AMERICA];
         yield ['America/Barbados', \DateTimeZone::AMERICA];
         yield ['Africa/Cairo', \DateTimeZone::AFRICA];
@@ -124,6 +144,7 @@ public function testInvalidTimezoneWithoutZone(string $timezone)
 
     public function getInvalidTimezones(): iterable
     {
+        yield ['Buenos_Aires/America'];
         yield ['Buenos_Aires/Argentina/America'];
         yield ['Mayotte/Indian'];
         yield ['foobar'];
@@ -149,11 +170,15 @@ public function testInvalidGroupedTimezones(string $timezone, int $zone)
 
     public function getInvalidGroupedTimezones(): iterable
     {
+        yield ['America/Buenos_Aires', \DateTimeZone::ASIA | \DateTimeZone::AUSTRALIA]; // icu
+        yield ['America/Argentina/Buenos_Aires', \DateTimeZone::EUROPE]; // php
         yield ['Antarctica/McMurdo', \DateTimeZone::AMERICA];
         yield ['America/Barbados', \DateTimeZone::ANTARCTICA];
         yield ['Europe/Kiev', \DateTimeZone::ARCTIC];
         yield ['Asia/Ho_Chi_Minh', \DateTimeZone::INDIAN];
         yield ['Asia/Ho_Chi_Minh', \DateTimeZone::INDIAN | \DateTimeZone::ANTARCTICA];
+        yield ['UTC', \DateTimeZone::EUROPE];
+        yield ['Etc/UTC', \DateTimeZone::EUROPE];
     }
 
     /**
@@ -173,6 +198,8 @@ public function testValidGroupedTimezonesByCountry(string $timezone, string $cou
 
     public function getValidGroupedTimezonesByCountry(): iterable
     {
+        yield ['America/Buenos_Aires', 'AR']; // icu
+        yield ['America/Argentina/Buenos_Aires', 'AR']; // php
         yield ['America/Argentina/Cordoba', 'AR'];
         yield ['America/Barbados', 'BB'];
         yield ['Africa/Cairo', 'EG'];
@@ -215,6 +242,7 @@ public function getInvalidGroupedTimezonesByCountry(): iterable
         yield ['America/Argentina/Cordoba', 'FR'];
         yield ['America/Barbados', 'PT'];
         yield ['Europe/Bern', 'FR'];
+        yield ['Etc/UTC', 'NL'];
         yield ['Europe/Amsterdam', 'AC']; // "AC" has no timezones, but is a valid country code
     }
 
@@ -267,8 +295,6 @@ public function testDeprecatedTimezonesAreInvalidWithoutBC(string $timezone)
 
     public function getDeprecatedTimezones(): iterable
     {
-        yield ['America/Buenos_Aires'];
-        yield ['America/Montreal'];
         yield ['Australia/ACT'];
         yield ['Australia/LHI'];
         yield ['Australia/Queensland'];
@@ -277,13 +303,29 @@ public function getDeprecatedTimezones(): iterable
         yield ['Canada/Mountain'];
         yield ['Canada/Pacific'];
         yield ['CET'];
-        yield ['CST6CDT'];
-        yield ['Etc/GMT'];
+        yield ['GMT'];
         yield ['Etc/Greenwich'];
         yield ['Etc/UCT'];
         yield ['Etc/Universal'];
-        yield ['Etc/UTC'];
         yield ['Etc/Zulu'];
         yield ['US/Pacific'];
     }
+
+    /**
+     * @requires extension intl
+     */
+    public function testIntlCompatibility()
+    {
+        $constraint = new Timezone([
+            'message' => 'myMessage',
+            'intlCompatible' => true,
+        ]);
+
+        $this->validator->validate('Europe/Saratov', $constraint);
+
+        $this->buildViolation('myMessage')
+            ->setParameter('{{ value }}', '"Europe/Saratov"')
+            ->setCode(Timezone::TIMEZONE_IDENTIFIER_INTL_ERROR)
+            ->assertRaised();
+    }
 }