From d36992057cde9bda186280dadf59fce0e992df46 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Krier?= <ced@b2ck.com>
Date: Thu, 24 Nov 2022 19:22:28 +0100
Subject: [PATCH] Do not convert empty grouped date when computing quantities

When there is a move without planned nor effective date, the computed date is
None.

issue11895
review418731005
---
 move.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/move.py b/move.py
index 40953250a0..d3752d3640 100644
--- a/move.py
+++ b/move.py
@@ -1569,7 +1569,7 @@ class Move(Workflow, ModelSQL, ModelView):
             key = list(line[1:-1])
             if 'date' in grouping:
                 i = grouping.index('date')
-                if not isinstance(key[i], datetime.date):
+                if key[i] and not isinstance(key[i], datetime.date):
                     key[i] = datetime.date.fromisoformat(key[i])
             key = tuple(key)
             quantity = line[-1]