From 027fd1242cfaf3ae26856f94c01d2b7c04705172 Mon Sep 17 00:00:00 2001
From: "Paul \"LeoNerd\" Evans" <paul@matrix.org>
Date: Wed, 4 Mar 2015 17:32:28 +0000
Subject: [PATCH] Give LruCache a __len__, so that  len(cache)  works

---
 synapse/util/lrucache.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/synapse/util/lrucache.py b/synapse/util/lrucache.py
index a45c673d32..f115f50e50 100644
--- a/synapse/util/lrucache.py
+++ b/synapse/util/lrucache.py
@@ -88,11 +88,15 @@ class LruCache(object):
             else:
                 return default
 
+        def cache_len():
+            return len(cache)
+
         self.sentinel = object()
         self.get = cache_get
         self.set = cache_set
         self.setdefault = cache_set_default
         self.pop = cache_pop
+        self.len = cache_len
 
     def __getitem__(self, key):
         result = self.get(key, self.sentinel)
@@ -108,3 +112,6 @@ class LruCache(object):
         result = self.pop(key, self.sentinel)
         if result is self.sentinel:
             raise KeyError()
+
+    def __len__(self):
+        return self.len()