first commit

__init__.py

@@ -0,0 +1 @@
+from . import models

__manifest__.py

@@ -0,0 +1,16 @@
+# -*- coding: utf-8 -*-
+{
+    'name': 'Account Shared Bank Cash',
+    'version': '1.0',
+    'category': 'Accounting',
+    'summary': 'Allows Bank & Cash accounts to be shared between companies',
+    'description': """
+This module removes the standard restriction that prevents Chart of Accounts (COA) of type 'Bank and Cash' from being shared across multiple companies.
+    """,
+    'author': 'Antigravity',
+    'depends': ['account'],
+    'data': [],
+    'installable': True,
+    'application': False,
+    'license': 'LGPL-3',
+}

models/__init__.py

@@ -0,0 +1 @@
+from . import account_account

models/account_account.py

@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+from odoo import api, models, _
+from odoo.exceptions import ValidationError, UserError
+
+class AccountAccount(models.Model):
+    _inherit = 'account.account'
+
+    @api.constrains('company_ids', 'account_type')
+    def _check_company_consistency(self):
+        if accounts_without_company := self.filtered(lambda a: not a.sudo().company_ids):
+            raise ValidationError(
+                self.env._(
+                    "The following accounts must be assigned to at least one company:\n%(accounts)s",
+                    accounts="\n".join(f"- {account.display_name}" for account in accounts_without_company),
+                ),
+            )
+        
+        # We explicitly REMOVE the check preventing 'asset_cash' accounts from having len(company_ids) > 1
+        # The standard Odoo validation below was removed:
+        # if self.filtered(lambda a: a.account_type == 'asset_cash' and len(a.company_ids) > 1):
+        #     raise ValidationError(_("Bank & Cash accounts cannot be shared between companies."))
+
+        # Need to invalidate the sudo cache as we might have just written on `company_ids`
+        self.invalidate_recordset(fnames=['company_ids'])
+        for companies, accounts in self.grouped(lambda a: a.company_ids).items():
+            if self.env['account.move.line'].sudo().search_count([
+                ('account_id', 'in', accounts.ids),
+                '!', ('company_id', 'child_of', companies.ids)
+            ], limit=1):
+                raise UserError(_("You can't unlink this company from this account since there are some journal items linked to it."))