bug #32796 [Cache] fix warning on PHP 7.4 (jpauli)

This PR was merged into the 3.4 branch.

Discussion
----------

[Cache] fix warning on PHP 7.4

| Q             | A
| ------------- | ---
| Branch?       | 4.3
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | not all, still some missing I cant find
| Fixed tickets |
| License       | MIT
| Doc PR        |

Some fixes in tests for PHP 7.4

Commits
-------

3324505 [Cache] fix warning on PHP 7.4

src/Symfony/Component/Cache/Adapter/AbstractAdapter.php

@@ -49,7 +49,7 @@ protected function __construct($namespace = '', $defaultLifetime = 0)
             throw new InvalidArgumentException(sprintf('Namespace must be %d chars max, %d given ("%s")', $this->maxIdLength - 24, \strlen($namespace), $namespace));
         }
         $this->createCacheItem = \Closure::bind(
-            function ($key, $value, $isHit) use ($defaultLifetime) {
+            static function ($key, $value, $isHit) use ($defaultLifetime) {
                 $item = new CacheItem();
                 $item->key = $key;
                 $item->value = $value;
@@ -63,7 +63,7 @@ function ($key, $value, $isHit) use ($defaultLifetime) {
         );
         $getId = function ($key) { return $this->getId((string) $key); };
         $this->mergeByLifetime = \Closure::bind(
-            function ($deferred, $namespace, &$expiredIds) use ($getId) {
+            static function ($deferred, $namespace, &$expiredIds) use ($getId) {
                 $byLifetime = [];
                 $now = time();
                 $expiredIds = [];

src/Symfony/Component/Cache/Adapter/ArrayAdapter.php

@@ -34,7 +34,7 @@ public function __construct($defaultLifetime = 0, $storeSerialized = true)
     {
         $this->storeSerialized = $storeSerialized;
         $this->createCacheItem = \Closure::bind(
-            function ($key, $value, $isHit) use ($defaultLifetime) {
+            static function ($key, $value, $isHit) use ($defaultLifetime) {
                 $item = new CacheItem();
                 $item->key = $key;
                 $item->value = $value;

src/Symfony/Component/Cache/Adapter/ChainAdapter.php

@@ -56,7 +56,7 @@ public function __construct(array $adapters, $defaultLifetime = 0)
         $this->adapterCount = \count($this->adapters);
 
         $this->syncItem = \Closure::bind(
-            function ($sourceItem, $item) use ($defaultLifetime) {
+            static function ($sourceItem, $item) use ($defaultLifetime) {
                 $item->value = $sourceItem->value;
                 $item->expiry = $sourceItem->expiry;
                 $item->isHit = $sourceItem->isHit;

src/Symfony/Component/Cache/Adapter/PhpArrayAdapter.php

@@ -42,7 +42,7 @@ public function __construct($file, AdapterInterface $fallbackPool)
         $this->pool = $fallbackPool;
         $this->zendDetectUnicode = filter_var(ini_get('zend.detect_unicode'), FILTER_VALIDATE_BOOLEAN);
         $this->createCacheItem = \Closure::bind(
-            function ($key, $value, $isHit) {
+            static function ($key, $value, $isHit) {
                 $item = new CacheItem();
                 $item->key = $key;
                 $item->value = $value;

src/Symfony/Component/Cache/Adapter/ProxyAdapter.php

@@ -42,7 +42,7 @@ public function __construct(CacheItemPoolInterface $pool, $namespace = '', $defa
         $this->namespace = '' === $namespace ? '' : CacheItem::validateKey($namespace);
         $this->namespaceLen = \strlen($namespace);
         $this->createCacheItem = \Closure::bind(
-            function ($key, $innerItem) use ($defaultLifetime, $poolHash) {
+            static function ($key, $innerItem) use ($defaultLifetime, $poolHash) {
                 $item = new CacheItem();
                 $item->key = $key;
                 $item->defaultLifetime = $defaultLifetime;

src/Symfony/Component/Cache/Adapter/TagAwareAdapter.php

@@ -42,7 +42,7 @@ public function __construct(AdapterInterface $itemsPool, AdapterInterface $tagsP
         $this->tags = $tagsPool ?: $itemsPool;
         $this->knownTagVersionsTtl = $knownTagVersionsTtl;
         $this->createCacheItem = \Closure::bind(
-            function ($key, $value, CacheItem $protoItem) {
+            static function ($key, $value, CacheItem $protoItem) {
                 $item = new CacheItem();
                 $item->key = $key;
                 $item->value = $value;
@@ -56,7 +56,7 @@ function ($key, $value, CacheItem $protoItem) {
             CacheItem::class
         );
         $this->setCacheItemTags = \Closure::bind(
-            function (CacheItem $item, $key, array &$itemTags) {
+            static function (CacheItem $item, $key, array &$itemTags) {
                 if (!$item->isHit) {
                     return $item;
                 }
@@ -76,7 +76,7 @@ function (CacheItem $item, $key, array &$itemTags) {
             CacheItem::class
         );
         $this->getTagsByKey = \Closure::bind(
-            function ($deferred) {
+            static function ($deferred) {
                 $tagsByKey = [];
                 foreach ($deferred as $key => $item) {
                     $tagsByKey[$key] = $item->tags;
@@ -88,7 +88,7 @@ function ($deferred) {
             CacheItem::class
         );
         $this->invalidateTags = \Closure::bind(
-            function (AdapterInterface $tagsAdapter, array $tags) {
+            static function (AdapterInterface $tagsAdapter, array $tags) {
                 foreach ($tags as $v) {
                     $v->defaultLifetime = 0;
                     $v->expiry = null;

src/Symfony/Component/Cache/Simple/Psr6Cache.php

@@ -41,7 +41,7 @@ public function __construct(CacheItemPoolInterface $pool)
         }
         $cacheItemPrototype = &$this->cacheItemPrototype;
         $createCacheItem = \Closure::bind(
-            function ($key, $value, $allowInt = false) use (&$cacheItemPrototype) {
+            static function ($key, $value, $allowInt = false) use (&$cacheItemPrototype) {
                 $item = clone $cacheItemPrototype;
                 $item->key = $allowInt && \is_int($key) ? (string) $key : CacheItem::validateKey($key);
                 $item->value = $value;

src/Symfony/Component/ExpressionLanguage/ParserCache/ParserCacheAdapter.php

@@ -30,7 +30,7 @@ public function __construct(ParserCacheInterface $pool)
         $this->pool = $pool;
 
         $this->createCacheItem = \Closure::bind(
-            function ($key, $value, $isHit) {
+            static function ($key, $value, $isHit) {
                 $item = new CacheItem();
                 $item->key = $key;
                 $item->value = $value;

src/Symfony/Component/Routing/Loader/PhpFileLoader.php

@@ -40,7 +40,7 @@ public function load($file, $type = null)
 
         // the closure forbids access to the private scope in the included file
         $loader = $this;
-        $load = \Closure::bind(function ($file) use ($loader) {
+        $load = \Closure::bind(static function ($file) use ($loader) {
             return include $file;
         }, null, ProtectedPhpFileLoader::class);