From faba6daf7c8f95bfc865cc3f59297070c59e3e3b Mon Sep 17 00:00:00 2001
From: Raphael Collet <rco@odoo.com>
Date: Mon, 8 May 2017 17:23:34 +0200
Subject: [PATCH] [FIX] models: attribute `pool` on a model's class's may be
 falsy but not `None`

Modify the test to match `None` instead of any falsy value.  The latter
triggers a bug when installing a just-deinstalled module (point_of_sale).
---
 odoo/models.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/odoo/models.py b/odoo/models.py
index c0a995e4405..264b9e45955 100644
--- a/odoo/models.py
+++ b/odoo/models.py
@@ -2768,7 +2768,7 @@ class BaseModel(object):
         cls = type(self)
         cls._setup_done = False
         # a model's base structure depends on its mro (without registry classes)
-        cls._model_cache_key = tuple(c for c in cls.mro() if not getattr(c, 'pool', None))
+        cls._model_cache_key = tuple(c for c in cls.mro() if getattr(c, 'pool', None) is None)
 
     @api.model
     def _setup_base(self, partial):