fix(Auth): retain expiration in FileSystemCacheItemPool and return null in CacheTrait

Auth/src/Cache/FileSystemCacheItemPool.php

@@ -64,21 +64,26 @@ public function getItem(string $key): CacheItemInterface
             );
         }
 
-        $item = new TypedItem($key);
-
         $itemPath = $this->cacheFilePath($key);
 
         if (!file_exists($itemPath)) {
-            return $item;
+            return new TypedItem($key);
         }
 
         $serializedItem = file_get_contents($itemPath);
 
         if ($serializedItem === false) {
-            return $item;
+            return new TypedItem($key);
+        }
+
+        $data = unserialize($serializedItem);
+
+        if ($data instanceof CacheItemInterface) {
+            return $data;
         }
 
-        $item->set(unserialize($serializedItem));
+        $item = new TypedItem($key);
+        $item->set($data);
 
         return $item;
     }
@@ -113,7 +118,7 @@ public function save(CacheItemInterface $item): bool
         }
 
         $itemPath = $this->cacheFilePath($item->getKey());
-        $serializedItem = serialize($item->get());
+        $serializedItem = serialize($item);
 
         $result = file_put_contents($itemPath, $serializedItem, LOCK_EX);
 

Auth/src/CacheTrait.php

@@ -59,6 +59,8 @@ private function getCachedValue($k)
         if ($cacheItem->isHit()) {
             return $cacheItem->get();
         }
+
+        return null;
     }
 
     /**

Auth/tests/Cache/FileSystemCacheItemPoolTest.php

@@ -17,6 +17,7 @@
 
 namespace Google\Auth\Tests\Cache;
 
+use DateTime;
 use Google\Auth\Cache\FileSystemCacheItemPool;
 use Google\Auth\Cache\TypedItem;
 use PHPUnit\Framework\TestCase;
@@ -66,6 +67,29 @@ public function testSaveAndGetItem()
         $this->assertEquals($retrievedItem->get(), $item->get());
     }
 
+    public function testSaveAndGetExpiredItem()
+    {
+        $item = $this->getNewItem();
+        $item->expiresAt(new DateTime('yesterday'));
+        $this->pool->save($item);
+        $retrievedItem = $this->pool->getItem($item->getKey());
+
+        $this->assertFalse($retrievedItem->isHit());
+        $this->assertNull($retrievedItem->get());
+    }
+
+    public function testGetItemLegacyCacheFile()
+    {
+        $key = 'LegacyItem';
+        $itemPath = $this->cachePath . '/' . $key;
+        file_put_contents($itemPath, serialize('legacyValue'));
+
+        $retrievedItem = $this->pool->getItem($key);
+
+        $this->assertTrue($retrievedItem->isHit());
+        $this->assertEquals('legacyValue', $retrievedItem->get());
+    }
+
     public function testHasItem()
     {
         $item = $this->getNewItem();

Auth/tests/CacheTraitTest.php

@@ -58,6 +58,25 @@ public function testSuccessfullyPullsFromCache()
         $this->assertEquals($expectedValue, $cachedValue);
     }
 
+    public function testFailsPullFromCacheWhenItemIsNotHit()
+    {
+        $this->mockCacheItem->isHit()
+            ->shouldBeCalledTimes(1)
+            ->willReturn(false);
+        $this->mockCacheItem->get()
+            ->shouldNotBeCalled();
+        $this->mockCache->getItem('key')
+            ->shouldBeCalledTimes(1)
+            ->willReturn($this->mockCacheItem->reveal());
+
+        $implementation = $this->getCacheTraitImplementation([
+            'cache' => $this->mockCache->reveal(),
+        ]);
+
+        $cachedValue = $implementation->getCachedValue('key');
+        $this->assertNull($cachedValue);
+    }
+
     public function testSuccessfullyPullsFromCacheWithInvalidKey()
     {
         $key = 'this-key-has-@-illegal-characters';