Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

vendor/doctrine/cache/lib/Doctrine/Common/Cache/PredisCache.php

@@ -0,0 +1,107 @@
+<?php
+
+namespace Doctrine\Common\Cache;
+
+use Predis\Client;
+
+/**
+ * Predis cache provider.
+ *
+ * @author othillo <othillo@othillo.nl>
+ */
+class PredisCache extends CacheProvider
+{
+    /**
+     * @var Client
+     */
+    private $client;
+
+    /**
+     * @param Client $client
+     *
+     * @return void
+     */
+    public function __construct(Client $client)
+    {
+        $this->client = $client;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doFetch($id)
+    {
+        $result = $this->client->get($id);
+        if (null === $result) {
+            return false;
+        }
+
+        return unserialize($result);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doFetchMultiple(array $keys)
+    {
+        $fetchedItems = call_user_func_array(array($this->client, 'mget'), $keys);
+
+        return array_filter(array_combine($keys, array_map('unserialize', $fetchedItems)));
+    }
+    /**
+     * {@inheritdoc}
+     */
+    protected function doContains($id)
+    {
+        return $this->client->exists($id);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doSave($id, $data, $lifeTime = 0)
+    {
+        $data = serialize($data);
+        if ($lifeTime > 0) {
+            $response = $this->client->setex($id, $lifeTime, $data);
+        } else {
+            $response = $this->client->set($id, $data);
+        }
+
+        return $response === true || $response == 'OK';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doDelete($id)
+    {
+        return $this->client->del($id) > 0;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doFlush()
+    {
+        $response = $this->client->flushdb();
+
+        return $response === true || $response == 'OK';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doGetStats()
+    {
+        $info = $this->client->info();
+
+        return array(
+            Cache::STATS_HITS              => $info['Stats']['keyspace_hits'],
+            Cache::STATS_MISSES            => $info['Stats']['keyspace_misses'],
+            Cache::STATS_UPTIME            => $info['Server']['uptime_in_seconds'],
+            Cache::STATS_MEMORY_USAGE      => $info['Memory']['used_memory'],
+            Cache::STATS_MEMORY_AVAILABLE  => false
+        );
+    }
+}