Ticket #10646: memcache_incr_decr_require_key.patch

django/core/cache/backends/memcached.py

@@ -45 +45 @@
     def close(self, **kwargs):
         self._cache.disconnect_all()
 
+    def require_key(self, key):
+        if key not in self:
+            raise ValueError("Key '%s' not found!")
+
     def incr(self, key, delta=1):
+        self.require_key(key)
         return self._cache.incr(key, delta)
 
     def decr(self, key, delta=1):
+        self.require_key(key)
         return self._cache.decr(key, delta)