Merge branch '5.2' into 5.3

* 5.2:
  [DI] fix fixture
  [ErrorHandler] fix handling buffered SilencedErrorContext
  [HttpClient] fix Psr18Client when allow_url_fopen=0
  [DependencyInjection] Add support of PHP enumerations
  [Cache] handle prefixed redis connections when clearing pools
  [Cache] fix eventual consistency when using RedisTagAwareAdapter with a cluster
  [Uid] Fix fromString() with low base58 values
  [Validator][Translation] Add ExpressionLanguageSyntax en and fr
  [HttpKernel] [HttpCache] Keep s-maxage=0 from ESI sub-responses
  Avoid broken action URL in text notification mail
  [Cache] Disable locking on Windows by default
  [DependencyInjection] Fix binding "iterable $foo" when using the PHP-DSL
  [Config] fix tracking default values that reference the parent class
  [DependencyInjection] fix accepted types on FactoryTrait::factory()
  [VarDumper] Fix tests for PHP 8.1
  [Mailer] fix encoding of addresses using SmtpTransport
  [MonologBridge] Fix the server:log help --filter sample

Author: nicolas-grekas

Inline.php

@@ -127,6 +127,8 @@ public static function dump($value, int $flags = 0): string
                 return self::dumpNull($flags);
             case $value instanceof \DateTimeInterface:
                 return $value->format('c');
+            case $value instanceof \UnitEnum:
+                return sprintf('!php/const %s::%s', \get_class($value), $value->name);
             case \is_object($value):
                 if ($value instanceof TaggedValue) {
                     return '!'.$value->getTag().' '.self::dump($value->getValue(), $flags);

Tests/Fixtures/FooUnitEnum.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace Symfony\Component\Yaml\Tests\Fixtures;
+
+enum FooUnitEnum
+{
+    case BAR;
+}

Tests/InlineTest.php

@@ -16,6 +16,7 @@
 use Symfony\Component\Yaml\Exception\ParseException;
 use Symfony\Component\Yaml\Inline;
 use Symfony\Component\Yaml\Tag\TaggedValue;
+use Symfony\Component\Yaml\Tests\Fixtures\FooUnitEnum;
 use Symfony\Component\Yaml\Yaml;
 
 class InlineTest extends TestCase
@@ -580,6 +581,14 @@ public function testDumpDateTime($dateTime, $expected)
         $this->assertSame($expected, Inline::dump($dateTime));
     }
 
+    /**
+     * @requires PHP 8.1
+     */
+    public function testDumpUnitEnum()
+    {
+        $this->assertSame("!php/const Symfony\Component\Yaml\Tests\Fixtures\FooUnitEnum::BAR", Inline::dump(FooUnitEnum::BAR));
+    }
+
     public function getDateTimeDumpTests()
     {
         $tests = [];