bug symfony#44232 [Cache] fix connecting to local Redis sockets (nicolas-grekas)

This PR was merged into the 4.4 branch.

Discussion
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[Cache] fix connecting to local Redis sockets

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix symfony#44215
| License       | MIT
| Doc PR        | -

Commits
-------

954db3f [Cache] fix connecting to local Redis sockets

Author: nicolas-grekas

src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php

@@ -96,6 +96,7 @@ public function provideFailedCreateConnection(): array
             ['redis://localhost:1234'],
             ['redis://foo@localhost'],
             ['redis://localhost/123'],
+            ['redis:///some/local/path'],
         ];
     }
 

src/Symfony/Component/Cache/Traits/RedisTrait.php

@@ -151,7 +151,7 @@ public static function createConnection($dsn, array $options = [])
                 if (preg_match('#/(\d+)$#', $params['path'], $m)) {
                     $params['dbindex'] = $m[1];
                     $params['path'] = substr($params['path'], 0, -\strlen($m[0]));
-                } else {
+                } elseif (isset($params['host'])) {
                     throw new InvalidArgumentException(sprintf('Invalid Redis DSN: "%s", the "dbindex" parameter must be a number.', $dsn));
                 }
             }