@@ -1,3 +1,9 @@
+## 8.1.3
+#### _"Don't throw the masks, yet."_
+##### _date to be defined_
+- __Core__
+- Fixed #860 // Cache item throw an error on save with DateTimeImmutable date objects
+
 ## 8.1.2
 #### _"Free the masks"_
 ##### 04 march 2022

@@ -162,7 +162,7 @@ public function expiresAt($expiration): ExtendedCacheItemInterface
 * @param DateTimeInterface $expiration
 */
 $this->eventManager->dis('CacheItemExpireAt', $this, $expiration);
-$this->expirationDate = $expiration;
+$this->expirationDate = $this->demutateDatetime($expiration);
 } else {
 throw new PhpfastcacheInvalidArgumentException('$expiration must be an object implementing the DateTimeInterface got: ' . \gettype($expiration));
 }
@@ -211,4 +211,11 @@ public function expiresAfter($time)
 
 return $this;
 }
+
+protected function demutateDatetime(\DateTimeInterface $dateTime): \DateTimeInterface
+{
+return $dateTime instanceof \DateTimeImmutable
+? \DateTime::createFromImmutable($dateTime)
+: $dateTime;
+}
 }

@@ -17,6 +17,7 @@
 namespace Phpfastcache\Core\Pool;
 
 use DateTime;
+use DateTimeInterface;
 use Exception;
 use Phpfastcache\Config\ConfigurationOption;
 use Phpfastcache\Core\Item\ExtendedCacheItemInterface;
@@ -179,27 +180,27 @@ public function driverUnwrapData(array $wrapper)
 
 /**
 * @param array $wrapper
-* @return DateTime
+* @return ?DateTimeInterface
 */
-public function driverUnwrapEdate(array $wrapper)
+public function driverUnwrapEdate(array $wrapper): ?DateTimeInterface
 {
 return $wrapper[self::DRIVER_EDATE_WRAPPER_INDEX];
 }
 
 /**
 * @param array $wrapper
-* @return DateTime
+* @return ?DateTimeInterface
 */
-public function driverUnwrapCdate(array $wrapper)
+public function driverUnwrapCdate(array $wrapper): ?DateTimeInterface
 {
 return $wrapper[self::DRIVER_CDATE_WRAPPER_INDEX];
 }
 
 /**
 * @param array $wrapper
-* @return DateTime
+* @return ?DateTimeInterface
 */
-public function driverUnwrapMdate(array $wrapper)
+public function driverUnwrapMdate(array $wrapper) :?DateTimeInterface
 {
 return $wrapper[self::DRIVER_MDATE_WRAPPER_INDEX];
 }

@@ -0,0 +1,34 @@
+<?php
+
+/**
+* @author Khoa Bui (khoaofgod) <[email protected]> https://www.phpfastcache.com
+* @author Georges.L (Geolim4) <[email protected]>
+*/
+
+use Phpfastcache\CacheManager;
+use Phpfastcache\Drivers\Files\Config as FilesConfig;
+use Phpfastcache\Tests\Helper\TestHelper;
+
+chdir(__DIR__);
+require_once __DIR__ . '/../../vendor/autoload.php';
+$testHelper = new TestHelper(' issue #860 - Cache item throw an error on save with DateTimeImmutable date objects');
+
+$config = new FilesConfig();
+$config->setItemDetailedDate(true);
+$cacheInstance = CacheManager::getInstance('Files', $config);
+$cacheInstance->clear();
+
+try {
+$key = 'pfc_' . bin2hex(random_bytes(12));
+$item = $cacheInstance->getItem($key);
+$item->set(random_int(1000, 999999))
+->setExpirationDate(new DateTimeImmutable('+1 month'))
+->setCreationDate(new DateTimeImmutable())
+->setModificationDate(new DateTimeImmutable('+1 week'));
+$cacheInstance->save($item);
+$cacheInstance->detachAllItems();
+$item = $cacheInstance->getItem($key);
+$testHelper->assertPass(' issue #860 have not regressed.');
+} catch (\TypeError $e) {
+$testHelper->assertFail(' issue #860 have regressed, exception caught: ' . $e->getMessage());
+}