Fixed multiple type issues revealed in #862

Author: Geolim4

lib/Phpfastcache/Core/Pool/DriverBaseTrait.php

@@ -269,6 +269,6 @@ protected function encode($data): string
      */
     protected function decode(?string $value): mixed
     {
-        return \unserialize((string) $value, ['allowed_classes' => true]);
+        return $value ? \unserialize($value, ['allowed_classes' => true]) : null;
     }
 }

lib/Phpfastcache/Drivers/Apcu/Driver.php

@@ -92,7 +92,7 @@ protected function driverRead(ExtendedCacheItemInterface $item): ?array
     {
         $data = apcu_fetch($item->getKey(), $success);
 
-        if ($success === false) {
+        if ($success === false || !\is_array($data)) {
             return null;
         }
 

lib/Phpfastcache/Drivers/Arangodb/Driver.php

@@ -131,7 +131,7 @@ protected function driverRead(ExtendedCacheItemInterface $item): ?array
                 return null;
             }
             throw new PhpfastcacheDriverException(
-                'Got unexpeced error from Arangodb: ' . $e->getMessage()
+                'Got unexpected error from Arangodb: ' . $e->getMessage()
             );
         }
 

lib/Phpfastcache/Drivers/Cassandra/Driver.php

@@ -140,7 +140,7 @@ protected function driverRead(ExtendedCacheItemInterface $item): ?array
             $results = $this->instance->execute(new Cassandra\SimpleStatement($query), $options);
 
             if ($results instanceof Cassandra\Rows && $results->count() === 1) {
-                return $this->decode($results->first()['cache_data']);
+                return $this->decode($results->first()['cache_data']) ?: null;
             }
 
             return null;

lib/Phpfastcache/Drivers/Couchdb/Driver.php

@@ -257,7 +257,7 @@ protected function encodeDocument(array $data): array
      * @return mixed
      * @throws \Exception
      */
-    protected function decode($value): mixed
+    protected function decode($value): array
     {
         $value[ExtendedCacheItemPoolInterface::DRIVER_DATA_WRAPPER_INDEX] = \unserialize(
             $value[ExtendedCacheItemPoolInterface::DRIVER_DATA_WRAPPER_INDEX],

lib/Phpfastcache/Drivers/Files/Driver.php

@@ -71,7 +71,7 @@ protected function driverRead(ExtendedCacheItemInterface $item): ?array
             return null;
         }
 
-        return $this->decode($content) ?: null;
+        return $this->decode($content);
     }
 
     /**

lib/Phpfastcache/Drivers/Memcache/Driver.php

@@ -149,7 +149,7 @@ protected function driverRead(ExtendedCacheItemInterface $item): ?array
     {
         $val = $this->instance->get($item->getKey());
 
-        if ($val === false) {
+        if (empty($val) || !\is_array($val)) {
             return null;
         }
 

lib/Phpfastcache/Drivers/Memcached/Driver.php

@@ -147,7 +147,7 @@ protected function driverRead(ExtendedCacheItemInterface $item): ?array
     {
         $val = $this->instance->get($item->getKey());
 
-        if ($val === false) {
+        if (empty($val) || !\is_array($val)) {
             return null;
         }
 

lib/Phpfastcache/Drivers/Predis/Driver.php

@@ -143,7 +143,8 @@ protected function driverConnect(): bool
     protected function driverRead(ExtendedCacheItemInterface $item): ?array
     {
         $val = $this->instance->get($item->getKey());
-        if ($val == false) {
+
+        if ($val === null) {
             return null;
         }
 

lib/Phpfastcache/Drivers/Ssdb/Driver.php

@@ -94,7 +94,8 @@ protected function driverConnect(): bool
     protected function driverRead(ExtendedCacheItemInterface $item): ?array
     {
         $val = $this->instance->get($item->getEncodedKey());
-        if (!$val) {
+
+        if (empty($val)) {
             return null;
         }