[FIX] website: compute company id for new users

When a new user is created from the website, the company id was always
set to the first company of the database even if the website was the one
of another company. This flow has been already fixed if there is the
"Specific User Account" setting activated (see [this other commit]).
This commit fixes the same issue but for every case.

Steps to reproduce the issue:
- Create 2 companies A & B
- For each company, create a website linked to a different URL
- Activate 'Free sign up' for company B
- As a public user, go to website of company B
- Go to 'Sign in > Don't have an account?' and create an account

=> If as an admin you check the company of the created user, it is
company A instead of company B.

[this other commit]: https://github.com/odoo/odoo/commit/77c708c516beb322df37220634e178ba82e894c9



task-3277317

closes odoo/odoo#120475

Signed-off-by: Benoit Socias (bso) <bso@odoo.com>

addons/website/models/res_users.py

@@ -48,9 +48,12 @@ class ResUsers(models.Model):
     @api.model
     def _signup_create_user(self, values):
         current_website = self.env['website'].get_current_website()
+        # Note that for the moment, portal users can connect to all websites of
+        # all companies as long as the specific_user_account setting is not
+        # activated.
+        values['company_id'] = current_website.company_id.id
+        values['company_ids'] = [(4, current_website.company_id.id)]
         if request and current_website.specific_user_account:
-            values['company_id'] = current_website.company_id.id
-            values['company_ids'] = [(4, current_website.company_id.id)]
             values['website_id'] = current_website.id
         new_user = super(ResUsers, self)._signup_create_user(values)
         return new_user

addons/website/tests/test_res_users.py

@@ -7,6 +7,7 @@ from odoo.tests.common import TransactionCase, new_test_user
 from odoo.exceptions import ValidationError
 from odoo.service.model import check
 from odoo.tools import mute_logger
+from odoo.addons.website.tools import MockRequest
 
 
 class TestWebsiteResUsers(TransactionCase):
@@ -58,3 +59,40 @@ class TestWebsiteResUsers(TransactionCase):
         # not an IntegrityError
         with self.assertRaises(ValidationError), mute_logger('odoo.sql_db'):
             check_new_test_user(self.env.registry._db.dbname)
+
+    def _create_user_via_website(self, website, login):
+        # We need a fake request to _signup_create_user.
+        with MockRequest(self.env, website=website):
+            return self.env['res.users'].with_context(website_id=website.id)._signup_create_user({
+                'name': login,
+                'login': login,
+            })
+
+    def _create_and_check_portal_user(self, website_specific, company_1, company_2, website_1, website_2):
+        # Disable/Enable cross-website for portal users.
+        website_1.specific_user_account = website_specific
+        website_2.specific_user_account = website_specific
+
+        user_1 = self._create_user_via_website(website_1, 'user1')
+        user_2 = self._create_user_via_website(website_2, 'user2')
+        self.assertEqual(user_1.company_id, company_1)
+        self.assertEqual(user_2.company_id, company_2)
+
+        if website_specific:
+            self.assertEqual(user_1.website_id, website_1)
+            self.assertEqual(user_2.website_id, website_2)
+        else:
+            self.assertEqual(user_1.website_id.id, False)
+            self.assertEqual(user_2.website_id.id, False)
+
+    def test_multi_website_multi_company(self):
+        company_1 = self.env['res.company'].create({'name': "Company 1"})
+        company_2 = self.env['res.company'].create({'name': "Company 2"})
+        website_1 = self.env['website'].create({'name': "Website 1", 'company_id': company_1.id})
+        website_2 = self.env['website'].create({'name': "Website 2", 'company_id': company_2.id})
+        # Permit uninvited signup.
+        website_1.auth_signup_uninvited = 'b2c'
+        website_2.auth_signup_uninvited = 'b2c'
+
+        self._create_and_check_portal_user(False, company_1, company_2, website_1, website_2)
+        self._create_and_check_portal_user(True, company_1, company_2, website_1, website_2)