[FIX] account: tax lock tags

Despite the tax lock date, users are able to modify the tax report by adding tags.

Steps to reproduce:
Ensure the tax lock date is set
1. Journal Items list view
2. Edit one/many lines that
    - have a date before the tax lock date,
    - don't have a tax,
    - nor tax tags,
    - and is not a tax line.
3. Add a new tax tag

Issue:
The tax tags are added and might impact a tax report, when you should have received a user error.

Cause:
The `write` function calls the `_check_tax_lock_date` which in turn only checks the existing line
instead of the values given in the `write` parameters.
Since the line has no existing tax tags the check does not fail.

Solution:
Call the tax lock check both before and after writing the move line.

Task-5169152

closes odoo#233317

X-original-commit: e1c37c1
Signed-off-by: William André (wan) <[email protected]>
Signed-off-by: Habib Ayob (ayh) <[email protected]>

Author: h4818

addons/account/models/account_move_line.py

@@ -1701,6 +1701,7 @@ def write(self, vals):
         matching2lines = None  # lazy cache
         lines_to_unreconcile = self.env['account.move.line']
         st_lines_to_unreconcile = self.env['account.bank.statement.line']
+        tax_lock_check_ids = []
         for line in self:
             if not any(self.env['account.move']._field_will_change(line, vals, field_name) for field_name in vals):
                 line_to_write -= line
@@ -1715,7 +1716,7 @@ def write(self, vals):
 
             # Check the tax lock date.
             if line.parent_state == 'posted' and any(self.env['account.move']._field_will_change(line, vals, field_name) for field_name in protected_fields['tax']):
-                line._check_tax_lock_date()
+                tax_lock_check_ids.append(line.id)
 
             # Break the reconciliation.
             if (
@@ -1744,6 +1745,8 @@ def write(self, vals):
                 st_lines_to_unreconcile -= st_line
         st_lines_to_unreconcile.action_undo_reconciliation()
 
+        self.browse(tax_lock_check_ids)._check_tax_lock_date()
+
         move_container = {'records': self.move_id}
         with self.move_id._check_balanced(move_container),\
              self.env.protecting(self.env['account.move']._get_protected_vals(vals, self)),\
@@ -1778,6 +1781,9 @@ def write(self, vals):
             if any(field in vals for field in ['account_id', 'currency_id']):
                 self._check_constrains_account_id_journal_id()
 
+            # double check modified lines in case a tax field was changed on a line that didn't previously affect tax
+            self.browse(tax_lock_check_ids)._check_tax_lock_date()
+
             if not self.env.context.get('tracking_disable', False):
                 # Log changes to move lines on each move
                 for move_id, modified_lines in move_initial_values.items():

addons/account/tests/test_account_move_out_invoice.py

@@ -143,6 +143,13 @@ def setUp(self):
             self.term_line_vals_1,
         ], self.move_vals)
 
+    def test_basic_tax_lock(self):
+        tax_tag = self.env['account.account.tag'].create({'name': 'HiddenFromIRS', 'applicability': 'taxes'})
+        inv = self.init_invoice('out_invoice', amounts=[10], post=True)
+        inv.company_id.tax_lock_date = inv.date
+        with self.assertRaisesRegex(UserError, 'lock date'):
+            inv.line_ids.tax_tag_ids = tax_tag.ids
+
     @freeze_time('2020-01-15')
     def test_out_invoice_onchange_invoice_date(self):
         for tax_date, invoice_date, accounting_date in [