From 3c9897789fe37433df8f0d3f78729a3cf9d4d138 Mon Sep 17 00:00:00 2001
From: Abderrahim Kitouni <a.kitouni@gmail.com>
Date: Tue, 28 Jul 2009 15:31:07 +0100
Subject: [PATCH] ensure a tree is parsed before calculating its length

---
 dulwich/objects.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/dulwich/objects.py b/dulwich/objects.py
index 47fdc67..02d8d4b 100644
--- a/dulwich/objects.py
+++ b/dulwich/objects.py
@@ -430,6 +430,7 @@ def __delitem__(self, name):
         self._needs_serialization = True
 
     def __len__(self):
+        self._ensure_parsed()
         return len(self._entries)
 
     def add(self, mode, name, hexsha):