[14.0+] Option "Get warnings when invoicing specific customers" don't work correctly

[rafagf1]

Impacted versions
14.0, 15.0

Steps to reproduce

• Go to menu: Settings/Invoicing
• We mark the option: Warnings "Get warnings when invoicing specific customers"
• Edit "partner_1": in the "Internal Notes" tab we select the "Warning" or "Blocking Message" option in "Warning on the Invoice" combo and write a message.
• We create a purchase order or a sales order for that partner and press "Create Bill" (purchase order) or "Create Invoice" (sales order)

Current behavior

• It don't show the message and allows us to invoice even if we have selected the "Blocking Message" option.

Expected behavior

• It should show the warning message and if it's a blocking message, it should not allow the invoice to be made.

The "onchange" method of "account_move.partner_id" is executed:

odoo/addons/account/models/account_move.py

Line 433 in 869ed09

def _onchange_partner_id(self):

, but the dictionary that it returns with the warning isn't shown.

It only works if we create an invoice that don't come from a purchase or sale order.