[IMP] fields: check for inconsistent many2many definitions

closes #29323

odoo/addons/test_new_api/ir.model.access.csv

@@ -5,6 +5,7 @@ access_message,test_new_api_message,test_new_api.model_test_new_api_message,,1,1
 access_emailmessage,test_new_api_emailmessage,test_new_api.model_test_new_api_emailmessage,,1,1,1,1
 access_multi,test_new_api_multi,test_new_api.model_test_new_api_multi,,1,1,1,1
 access_multi_line,test_new_api_multi_line,test_new_api.model_test_new_api_multi_line,,1,1,1,1
+access_multi_line2,test_new_api_multi_line2,test_new_api.model_test_new_api_multi_line2,,1,1,1,1
 access_multi_tag,test_new_api_multi_tag,test_new_api.model_test_new_api_multi_tag,,1,1,1,1
 access_creativework_edition,test_new_api_creativework_edition,model_test_new_api_creativework_edition,,1,1,1,1
 access_creativework_book,test_new_api_creativework_book,model_test_new_api_creativework_book,,1,1,1,1

odoo/addons/test_new_api/models.py

@@ -225,6 +225,11 @@ class MultiLine(models.Model):
     tags = fields.Many2many('test_new_api.multi.tag')
 
 
+class MultiLine2(models.Model):
+    _name = 'test_new_api.multi.line2'
+    _inherit = 'test_new_api.multi.line'
+
+
 class MultiTag(models.Model):
     _name = 'test_new_api.multi.tag'
     _description = 'Test New API Multi Tag'

odoo/addons/test_new_api/tests/test_new_fields.py

@@ -1104,6 +1104,18 @@ def test_93_monetary_related(self):
 
 
 class TestX2many(common.TransactionCase):
+    def test_definition_many2many(self):
+        """ Test the definition of inherited many2many fields. """
+        field = self.env['test_new_api.multi.line']._fields['tags']
+        self.assertEqual(field.relation, 'test_new_api_multi_line_test_new_api_multi_tag_rel')
+        self.assertEqual(field.column1, 'test_new_api_multi_line_id')
+        self.assertEqual(field.column2, 'test_new_api_multi_tag_id')
+
+        field = self.env['test_new_api.multi.line2']._fields['tags']
+        self.assertEqual(field.relation, 'test_new_api_multi_line2_test_new_api_multi_tag_rel')
+        self.assertEqual(field.column1, 'test_new_api_multi_line2_id')
+        self.assertEqual(field.column2, 'test_new_api_multi_tag_id')
+
     def test_search_many2many(self):
         """ Tests search on many2many fields. """
         tags = self.env['test_new_api.multi.tag']

odoo/fields.py

@@ -2557,8 +2557,12 @@ def _setup_regular_full(self, model):
                 comodel = model.env[self.comodel_name]
                 model._field_inverses.add(self, invf)
                 comodel._field_inverses.add(invf, self)
-            else:
+
+            elif model._auto:
                 # add self in m2m, so that its inverse field can find it
+                if (self.relation, self.column1, self.column2) in m2m:
+                    msg = "Many2many fields %s and %s use the same table and columns"
+                    raise TypeError(msg % (self, m2m[(self.relation, self.column1, self.column2)]))
                 m2m[(self.relation, self.column1, self.column2)] = self
 
     def update_db(self, model, columns):