From f1806531c8c969a00a449575087542966afa0450 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nicolas=20=C3=89vrard?= <nicoe@b2ck.com>
Date: Wed, 25 May 2011 10:13:34 +0200
Subject: [PATCH] return list of invoice lines

---
 purchase.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/purchase.py b/purchase.py
index 05e84363bc..e2f6bd0a65 100644
--- a/purchase.py
+++ b/purchase.py
@@ -1104,7 +1104,7 @@ class PurchaseLine(ModelSQL, ModelView):
 
 
         if res['quantity'] <= 0.0:
-            return None
+            return []
         res['unit'] = line.unit.id
         res['product'] = line.product.id
         res['unit_price'] = line.unit_price