feature #19515 [Cache] Drop TaggedCacheItemInterface (nicolas-grekas)

This PR was merged into the 3.2-dev branch.

Discussion
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[Cache] Drop TaggedCacheItemInterface

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Introducing this interface was a mistake, we should drop it: the CacheItem class is final, and it can be instantiated only through a cache adapter. Which means there is no way to reuse this interface in any meaningful way as far as extensibility/interoperability is concerned.

Commits
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624890b [Cache] Drop TaggedCacheItemInterface

src/Symfony/Component/Cache/CacheItem.php

@@ -11,13 +11,14 @@
 
 namespace Symfony\Component\Cache;
 
+use Psr\Cache\CacheItemInterface;
 use Psr\Log\LoggerInterface;
 use Symfony\Component\Cache\Exception\InvalidArgumentException;
 
 /**
  * @author Nicolas Grekas <p@tchwork.com>
  */
-final class CacheItem implements TaggedCacheItemInterface
+final class CacheItem implements CacheItemInterface
 {
     protected $key;
     protected $value;
@@ -97,7 +98,13 @@ public function expiresAfter($time)
     }
 
     /**
-     * {@inheritdoc}
+     * Adds a tag to a cache item.
+     *
+     * @param string|string[] $tags A tag or array of tags
+     *
+     * @return static
+     *
+     * @throws InvalidArgumentException When $tag is not valid.
      */
     public function tag($tags)
     {