[FIX] *: remove en_US as fallback for lang code

en_US may not be activated as it is possible to create a database in
another language using the database manager.

When trying to install a chart of account, the tax return entry tried
to format a date at the installation of the module, with no lang in
the context. The fallback was made on en_US but an error is raised if
that language is not activated.

As it is a very common scenario to retrieve a language from the
context, add a generic tool method to do it.

Replace and closes odoo/odoo#37629

closes odoo/odoo#37568

Signed-off-by: Martin Trigaux (mat) <mat@odoo.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/addons/web/models/models.py b/addons/web/models/models.py
index e85de4f6c45..3ef871cabe0 100644
--- a/addons/web/models/models.py
+++ b/addons/web/models/models.py
@@ -5,6 +5,7 @@ import pytz
 from odoo import _, api, fields, models
 from odoo.osv.expression import AND
 from odoo.tools import lazy
+from odoo.tools.misc import get_lang
 from odoo.exceptions import UserError
 
 
@@ -142,7 +143,7 @@ class Base(models.AbstractModel):
 
             # Again, imitating what _read_group_format_result and _read_group_prepare_data do
             if group_by_value and field_type in ['date', 'datetime']:
-                locale = self._context.get('lang') or 'en_US'
+                locale = get_lang(self.env).code
                 group_by_value = fields.Datetime.to_datetime(group_by_value)
                 group_by_value = pytz.timezone('UTC').localize(group_by_value)
                 tz_info = None