[FIX] mail: add selection when fetching message type

A new message type was added in stable. This is usually safe,
however in cases where there are related fields on that same selection
fetching them will raise an exception as the ORM has to fetch the translations
for the selection in DB.

We add a hack on mail.mail to update the selections in DB when fetching
the message_type field for the first time.

task-3773301

closes odoo/odoo#156235

X-original-commit: 19683173708a2b029acb4e744871772b6c248715
Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>
Signed-off-by: Renaud Thiry (reth) <reth@odoo.com>

addons/mail/models/mail_mail.py

@@ -122,6 +122,24 @@ class MailMail(models.Model):
     def _search_body_content(self, operator, value):
         return [('body_html', operator, value)]
 
+    @api.model
+    def fields_get(self, *args, **kwargs):
+        # related selection will fetch translations from DB
+        # selections added in stable won't be in DB -> add them on the related model if not already added
+        message_type_field = self.env['mail.message']._fields['message_type']
+        if 'auto_comment' not in {value for value, name in message_type_field.get_description(self.env)['selection']}:
+            self._fields_get_message_type_update_selection(message_type_field.selection)
+        return super().fields_get(*args, **kwargs)
+
+    def _fields_get_message_type_update_selection(self, selection):
+        """Update the field selection for message type on mail.message to match the runtime values.
+
+        DO NOT USE it is only there for a stable fix and should not be used for any reason other than hotfixing.
+        """
+        self.env['ir.model.fields'].invalidate_model(['selection_ids'])
+        self.env['ir.model.fields.selection'].sudo()._update_selection('mail.message', 'message_type', selection)
+        self.env.registry.clear_cache()
+
     @api.model_create_multi
     def create(self, values_list):
         # notification field: if not set, set if mail comes from an existing mail.message

addons/mail/tests/__init__.py

@@ -4,6 +4,7 @@ from . import test_ir_mail_server
 from . import test_link_preview
 from . import test_mail_activity
 from . import test_mail_composer
+from . import test_mail_mail_stable_selection
 from . import test_mail_render
 from . import test_mail_template
 from . import test_mail_tools

addons/mail/tests/test_mail_mail_stable_selection.py

@@ -0,0 +1,16 @@
+
+
+from odoo.tests.common import TransactionCase
+
+class TestMailMailStableSelection(TransactionCase):
+    """Only relevant in stable as a hotfix. May be removed in master."""
+
+    def test_mail_mail_stable_selection(self):
+        # remove all selections
+        message_type_selections = self.env['ir.model.fields']._get('mail.message', 'message_type').selection_ids
+        message_type_selections.filtered(lambda s: s.value == 'auto_comment').unlink()
+        self.env['mail.mail']._fields_get_message_type_update_selection(self.env['mail.message']._fields['message_type'].selection)
+        # force convert to cache with specific language so it has to fetch related from DB
+        mail = self.env['mail.mail'].create({'subject': 'test', 'message_type': 'auto_comment'})
+        mail.invalidate_recordset(['message_type'])
+        self.assertEqual(mail.with_context(lang="en_US").message_type, 'auto_comment')