From 4a1f2c938b87f5527d48e180fe4711ff690be882 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Krier?= <ced@b2ck.com>
Date: Wed, 17 Jun 2020 00:30:53 +0200
Subject: [PATCH] Use different hash for records without id

In order to have store them efficiently in dictionary, we generate a different
hash for each unsaved record by using the instance id.

issue9240
review295421002
---
 trytond/model/model.py      |  2 +-
 trytond/tests/test_model.py | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/trytond/model/model.py b/trytond/model/model.py
index 993c296eb3..308c6b2720 100644
--- a/trytond/model/model.py
+++ b/trytond/model/model.py
@@ -316,7 +316,7 @@ class Model(URLMixin, PoolBase, metaclass=ModelMeta):
         return not self == other
 
     def __hash__(self):
-        return hash((self.__name__, self.id))
+        return hash((self.__name__, id(self) if self.id is None else self.id))
 
     def __bool__(self):
         return True
diff --git a/trytond/tests/test_model.py b/trytond/tests/test_model.py
index 1ecec11be9..09561fb8e2 100644
--- a/trytond/tests/test_model.py
+++ b/trytond/tests/test_model.py
@@ -30,6 +30,30 @@ class ModelTestCase(unittest.TestCase):
         self.assertEqual(
             repr(record), "Pool().get('test.model')(%s)" % record.id)
 
+    @with_transaction()
+    def test_hash_with_id(self):
+        "Test hash with id"
+        pool = Pool()
+        Model = pool.get('test.model')
+
+        record1 = Model(id=1)
+        record1bis = Model(id=1)
+        record2 = Model(id=2)
+
+        self.assertEqual(hash(record1), hash(record1bis))
+        self.assertNotEqual(hash(record1), hash(record2))
+
+    @with_transaction()
+    def test_hash_without_id(self):
+        "Test hash without id"
+        pool = Pool()
+        Model = pool.get('test.model')
+
+        record1 = Model()
+        record2 = Model()
+
+        self.assertNotEqual(hash(record1), hash(record2))
+
     @with_transaction()
     def test_init_parent(self):
         "Test __init__ with _parent_"