From e6f21f999e7848ab4b3fe601da3955c7812b7ee5 Mon Sep 17 00:00:00 2001
From: Nicolas Grekas <nicolas.grekas@gmail.com>
Date: Tue, 9 Feb 2016 09:52:25 +0100
Subject: [PATCH] [Cache] Count cache hits/misses in ProxyAdapter

---
 .../Component/Cache/Adapter/ProxyAdapter.php  | 37 ++++++++++++++++++-
 .../Cache/Tests/Adapter/ProxyAdapterTest.php  | 17 +++++++++
 2 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php b/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php
index 7e5c9aa20393d..eaeb5ba4fbd44 100644
--- a/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php
+++ b/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php
@@ -22,6 +22,8 @@ class ProxyAdapter implements CacheItemPoolInterface
 {
     private $pool;
     private $createCacheItem;
+    private $hits = 0;
+    private $misses = 0;
 
     public function __construct(CacheItemPoolInterface $pool)
     {
@@ -47,8 +49,13 @@ public function getItem($key)
     {
         $f = $this->createCacheItem;
         $item = $this->pool->getItem($key);
+        if ($isHit = $item->isHit()) {
+            ++$this->hits;
+        } else {
+            ++$this->misses;
+        }
 
-        return $f($key, $item->get(), $item->isHit());
+        return $f($key, $item->get(), $isHit);
     }
 
     /**
@@ -134,7 +141,33 @@ private function generateItems($items)
         $f = $this->createCacheItem;
 
         foreach ($items as $key => $item) {
-            yield $key => $f($key, $item->get(), $item->isHit());
+            if ($isHit = $item->isHit()) {
+                ++$this->hits;
+            } else {
+                ++$this->misses;
+            }
+
+            yield $key => $f($key, $item->get(), $isHit);
         }
     }
+
+    /**
+     * Returns the number of cache read hits.
+     *
+     * @return int
+     */
+    public function getHits()
+    {
+        return $this->hits;
+    }
+
+    /**
+     * Returns the number of cache read misses.
+     *
+     * @return int
+     */
+    public function getMisses()
+    {
+        return $this->misses;
+    }
 }
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/ProxyAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/ProxyAdapterTest.php
index 76606e256eea6..58594b0e1ef0d 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/ProxyAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/ProxyAdapterTest.php
@@ -29,4 +29,21 @@ public function createCachePool()
     {
         return new ProxyAdapter(new ArrayAdapter());
     }
+
+    public function testGetHitsMisses()
+    {
+        $pool = $this->createCachePool();
+
+        $this->assertSame(0, $pool->getHits());
+        $this->assertSame(0, $pool->getMisses());
+
+        $bar = $pool->getItem('bar');
+        $this->assertSame(0, $pool->getHits());
+        $this->assertSame(1, $pool->getMisses());
+
+        $pool->save($bar->set('baz'));
+        $bar = $pool->getItem('bar');
+        $this->assertSame(1, $pool->getHits());
+        $this->assertSame(1, $pool->getMisses());
+    }
 }