feature #33768 [String] Introduce a locale-aware Slugger in the Strin…

…g component (tgalopin)

This PR was merged into the 5.0-dev branch.

Discussion
----------

[String] Introduce a locale-aware Slugger in the String component

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | -
| License       | MIT
| Doc PR        | -

This PR introduces a locale-aware Slugger in the new String component, based on transliterators provided by the PHP intl extension (or iconv if not available). It also wires this Slugger in the FrameworkBundle in order to use it easily as a service and to automatically inject the proper locale into it to choose the appropriate transliteration depending on the Request locale.

See https://github.com/unicode-org/cldr/tree/master/common/transforms for CLDR mappings.

Commits
-------

056d8ce [String] Introduce a locale-aware Slugger in the String component with FrameworkBundle wiring

src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md

@@ -19,6 +19,7 @@ CHANGELOG
  * Removed `SecurityUserValueResolver`, use `UserValueResolver` instead
  * Removed `routing.loader.service`.
  * Service route loaders must be tagged with `routing.route_loader`. 
+ * Added `slugger` service and `SluggerInterface` alias
 
 4.4.0
 -----

src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php

@@ -105,6 +105,7 @@
 use Symfony\Component\Serializer\Normalizer\DenormalizerInterface;
 use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
 use Symfony\Component\Stopwatch\Stopwatch;
+use Symfony\Component\String\Slugger\SluggerInterface;
 use Symfony\Component\Translation\Command\XliffLintCommand as BaseXliffLintCommand;
 use Symfony\Component\Translation\Translator;
 use Symfony\Component\Validator\ConstraintValidatorInterface;
@@ -194,6 +195,12 @@ public function load(array $configs, ContainerBuilder $container)
             }
         }
 
+        // If the slugger is used but the String component is not available, we should throw an error
+        if (!class_exists(SluggerInterface::class)) {
+            $container->register('slugger', 'stdClass')
+                ->addError('You cannot use the "slugger" since the String component is not installed. Try running "composer require symfony/string".');
+        }
+
         if (isset($config['secret'])) {
             $container->setParameter('kernel.secret', $config['secret']);
         }

src/Symfony/Bundle/FrameworkBundle/Resources/config/services.xml

@@ -120,5 +120,11 @@
             <argument type="service" id="request_stack" />
             <tag name="kernel.event_subscriber" />
         </service>
+
+        <service id="slugger" class="Symfony\Component\String\Slugger\AsciiSlugger">
+            <argument>%kernel.default_locale%</argument>
+            <tag name="kernel.locale_aware" />
+        </service>
+        <service id="Symfony\Component\String\Slugger\SluggerInterface" alias="slugger" />
     </services>
 </container>

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/Bundle/TestBundle/Slugger/SlugConstructArgService.php

@@ -0,0 +1,29 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Tests\Functional\Bundle\TestBundle\Slugger;
+
+use Symfony\Component\String\Slugger\SluggerInterface;
+
+class SlugConstructArgService
+{
+    private $slugger;
+
+    public function __construct(SluggerInterface $slugger)
+    {
+        $this->slugger = $slugger;
+    }
+
+    public function hello(): string
+    {
+        return $this->slugger->slug('Стойността трябва да бъде лъжа');
+    }
+}

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/SluggerLocaleAwareTest.php

@@ -0,0 +1,28 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Tests\Functional;
+
+/**
+ * @group functional
+ */
+class SluggerLocaleAwareTest extends AbstractWebTestCase
+{
+    public function testLocalizedSlugger()
+    {
+        $kernel = static::createKernel(['test_case' => 'Slugger', 'root_config' => 'config.yml']);
+        $kernel->boot();
+
+        $service = $kernel->getContainer()->get('Symfony\Bundle\FrameworkBundle\Tests\Functional\Bundle\TestBundle\Slugger\SlugConstructArgService');
+
+        $this->assertSame('Stoinostta-tryabva-da-bude-luzha', $service->hello());
+    }
+}

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/app/Slugger/bundles.php

@@ -0,0 +1,18 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Symfony\Bundle\FrameworkBundle\FrameworkBundle;
+use Symfony\Bundle\FrameworkBundle\Tests\Functional\Bundle\TestBundle\TestBundle;
+
+return [
+    new FrameworkBundle(),
+    new TestBundle(),
+];

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/app/Slugger/config.yml

@@ -0,0 +1,14 @@
+imports:
+    - { resource: ../config/default.yml }
+    - { resource: services.yml }
+
+framework:
+    secret: '%secret%'
+    default_locale: '%env(LOCALE)%'
+    translator:
+        fallbacks:
+            - '%env(LOCALE)%'
+
+parameters:
+    env(LOCALE): bg
+    secret: test

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/app/Slugger/services.yml

@@ -0,0 +1,6 @@
+services:
+    _defaults:
+        public: true
+
+    Symfony\Bundle\FrameworkBundle\Tests\Functional\Bundle\TestBundle\Slugger\SlugConstructArgService:
+        arguments: ['@slugger']

src/Symfony/Bundle/FrameworkBundle/composer.json

@@ -50,6 +50,7 @@
         "symfony/security-http": "^4.4|^5.0",
         "symfony/serializer": "^4.4|^5.0",
         "symfony/stopwatch": "^4.4|^5.0",
+        "symfony/string": "^5.0",
         "symfony/translation": "^5.0",
         "symfony/twig-bundle": "^4.4|^5.0",
         "symfony/validator": "^4.4|^5.0",

src/Symfony/Component/String/AbstractUnicodeString.php

@@ -331,18 +331,6 @@ public function replaceMatches(string $fromPattern, $to): parent
         return $str;
     }
 
-    /**
-     * @return static
-     */
-    public function slug(string $separator = '-'): self
-    {
-        return $this
-            ->ascii()
-            ->replace('@', $separator.'at'.$separator)
-            ->replaceMatches('/[^A-Za-z0-9]++/', $separator)
-            ->trim($separator);
-    }
-
     public function snake(): parent
     {
         $str = $this->camel()->title();

src/Symfony/Component/String/Slugger/AsciiSlugger.php

@@ -0,0 +1,136 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\String\Slugger;
+
+use Symfony\Component\String\AbstractUnicodeString;
+use Symfony\Component\String\GraphemeString;
+use Symfony\Contracts\Translation\LocaleAwareInterface;
+
+/**
+ * @author Titouan Galopin <galopintitouan@gmail.com>
+ *
+ * @experimental in 5.0
+ */
+class AsciiSlugger implements SluggerInterface, LocaleAwareInterface
+{
+    private const LOCALE_TO_TRANSLITERATOR_ID = [
+        'am' => 'Amharic-Latin',
+        'ar' => 'Arabic-Latin',
+        'az' => 'Azerbaijani-Latin',
+        'be' => 'Belarusian-Latin',
+        'bg' => 'Bulgarian-Latin',
+        'bn' => 'Bengali-Latin',
+        'de' => 'de-ASCII',
+        'el' => 'Greek-Latin',
+        'fa' => 'Persian-Latin',
+        'he' => 'Hebrew-Latin',
+        'hy' => 'Armenian-Latin',
+        'ka' => 'Georgian-Latin',
+        'kk' => 'Kazakh-Latin',
+        'ky' => 'Kirghiz-Latin',
+        'ko' => 'Korean-Latin',
+        'mk' => 'Macedonian-Latin',
+        'mn' => 'Mongolian-Latin',
+        'or' => 'Oriya-Latin',
+        'ps' => 'Pashto-Latin',
+        'ru' => 'Russian-Latin',
+        'sr' => 'Serbian-Latin',
+        'sr_Cyrl' => 'Serbian-Latin',
+        'th' => 'Thai-Latin',
+        'tk' => 'Turkmen-Latin',
+        'uk' => 'Ukrainian-Latin',
+        'uz' => 'Uzbek-Latin',
+        'zh' => 'Han-Latin',
+    ];
+
+    private $defaultLocale;
+
+    /**
+     * Cache of transliterators per locale.
+     *
+     * @var \Transliterator[]
+     */
+    private $transliterators = [];
+
+    public function __construct(string $defaultLocale = null)
+    {
+        $this->defaultLocale = $defaultLocale;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function setLocale($locale)
+    {
+        $this->defaultLocale = $locale;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getLocale()
+    {
+        return $this->defaultLocale;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function slug(string $string, string $separator = '-', string $locale = null): AbstractUnicodeString
+    {
+        $locale = $locale ?? $this->defaultLocale;
+
+        $transliterator = [];
+        if ('de' === $locale || 0 === strpos($locale, 'de_')) {
+            // Use the shortcut for German in GraphemeString::ascii() if possible (faster and no requirement on intl)
+            $transliterator = ['de-ASCII'];
+        } elseif (\function_exists('transliterator_transliterate') && $locale) {
+            $transliterator = (array) $this->createTransliterator($locale);
+        }
+
+        return (new GraphemeString($string))
+            ->ascii($transliterator)
+            ->replace('@', $separator.'at'.$separator)
+            ->replaceMatches('/[^A-Za-z0-9]++/', $separator)
+            ->trim($separator)
+        ;
+    }
+
+    private function createTransliterator(string $locale): ?\Transliterator
+    {
+        if (isset($this->transliterators[$locale])) {
+            return $this->transliterators[$locale];
+        }
+
+        // Exact locale supported, cache and return
+        if ($id = self::LOCALE_TO_TRANSLITERATOR_ID[$locale] ?? null) {
+            return $this->transliterators[$locale] = \Transliterator::create($id.'/BGN') ?? \Transliterator::create($id);
+        }
+
+        // Locale not supported and no parent, fallback to any-latin
+        if (false === $str = strrchr($locale, '_')) {
+            return null;
+        }
+
+        // Try to use the parent locale (ie. try "de" for "de_AT") and cache both locales
+        $parent = substr($locale, 0, -\strlen($str));
+
+        if ($id = self::LOCALE_TO_TRANSLITERATOR_ID[$parent] ?? null) {
+            $transliterator = \Transliterator::create($id.'/BGN') ?? \Transliterator::create($id);
+            $this->transliterators[$locale] = $this->transliterators[$parent] = $transliterator;
+
+            return $transliterator;
+        }
+
+        return null;
+    }
+}

src/Symfony/Component/String/Slugger/SluggerInterface.php

@@ -0,0 +1,29 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\String\Slugger;
+
+use Symfony\Component\String\AbstractUnicodeString;
+
+/**
+ * Creates a URL-friendly slug from a given string.
+ *
+ * @author Titouan Galopin <galopintitouan@gmail.com>
+ *
+ * @experimental in 5.0
+ */
+interface SluggerInterface
+{
+    /**
+     * Creates a slug for the given string and locale, using appropriate transliteration when needed.
+     */
+    public function slug(string $string, string $separator = '-', string $locale = null): AbstractUnicodeString;
+}

src/Symfony/Component/String/Tests/SluggerTest.php

@@ -0,0 +1,49 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\String\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\String\Slugger\AsciiSlugger;
+
+class SluggerTest extends TestCase
+{
+    /**
+     * @requires extension intl
+     * @dataProvider provideSlug
+     */
+    public function testSlug(string $string, string $locale, string $expectedSlug)
+    {
+        $slugger = new AsciiSlugger($locale);
+
+        $this->assertSame($expectedSlug, (string) $slugger->slug($string));
+    }
+
+    public static function provideSlug(): array
+    {
+        return [
+            ['Стойността трябва да бъде лъжа', 'bg', 'Stoinostta-tryabva-da-bude-luzha'],
+            ['Dieser Wert sollte größer oder gleich', 'de', 'Dieser-Wert-sollte-groesser-oder-gleich'],
+            ['Dieser Wert sollte größer oder gleich', 'de_AT', 'Dieser-Wert-sollte-groesser-oder-gleich'],
+            ['Αυτή η τιμή πρέπει να είναι ψευδής', 'el', 'Avti-i-timi-prepi-na-inai-psevdhis'],
+            ['该变量的值应为', 'zh', 'gai-bian-liang-de-zhi-ying-wei'],
+            ['該變數的值應為', 'zh_TW', 'gai-bian-shu-de-zhi-ying-wei'],
+        ];
+    }
+
+    public function testSeparatorWithoutLocale()
+    {
+        $slugger = new AsciiSlugger();
+
+        $this->assertSame('hello-world', (string) $slugger->slug('hello world'));
+        $this->assertSame('hello_world', (string) $slugger->slug('hello world', '_'));
+    }
+}