[FIX] sql_db.py: fix error type raised by closed cursor

Since e014cc88394fb9c8f6cff556ca73d5efafea030f, our proxy
`Cursor` object doesn't return a understandable error when we
try to use it when it is already closed
(`NoneType` or `Recursion` error).

Instead of reverting e014cc88394fb9c8f6cff556ca73d5efafea030f,
add a check in `__getitem__` raising a IterfaceError (like psycopg)
if we try to use psycopg cursor (`self._obj`)

task-2766494

Part-of: odoo/odoo#85078

odoo/addons/base/tests/test_db_cursor.py

@@ -3,11 +3,12 @@
 import logging
 from functools import partial
 
+import psycopg2
+
 import odoo
 from odoo.sql_db import TestCursor
 from odoo.tests import common
 from odoo.tests.common import BaseCase
-from odoo.tools.misc import mute_logger
 
 ADMIN_USER_ID = common.ADMIN_USER_ID
 
@@ -15,10 +16,8 @@ def registry():
     return odoo.registry(common.get_db_name())
 
 
-class TestExecute(BaseCase):
-    """ Try cr.execute with wrong parameters """
+class TestRealCursor(BaseCase):
 
-    @mute_logger('odoo.sql_db')
     def test_execute_bad_params(self):
         """
         Try to use iterable but non-list or int params in query parameters.
@@ -31,6 +30,16 @@ class TestExecute(BaseCase):
             with self.assertRaises(ValueError):
                 cr.execute("SELECT id FROM res_users WHERE id=%s", '1')
 
+    def test_using_closed_cursor(self):
+        with registry().cursor() as cr:
+            cr.close()
+            with self.assertRaises(psycopg2.InterfaceError):
+                cr.execute("SELECT 1")
+
+    def test_multiple_close_call_cursor(self):
+        cr = registry().cursor()
+        cr.close()
+        cr.close()
 
 class TestTestCursor(common.TransactionCase):
     def setUp(self):

odoo/sql_db.py

@@ -539,6 +539,8 @@ class Cursor(BaseCursor):
         return result
 
     def __getattr__(self, name):
+        if self._closed and name == '_obj':
+            raise psycopg2.InterfaceError("Cursor already closed")
         return getattr(self._obj, name)
 
     @property