From b2bb8ec2d4209424e6d09db1bb3ceda5c4bcfa70 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Krier?= <ced@b2ck.com>
Date: Sat, 17 Jan 2026 12:53:33 +0100
Subject: [PATCH] Always return a date for tax date of TaxableMixin

Closes #14486
(grafted from b2ab8b67ca33fe466bc1be9712de08ec26d6ea80)

--HG--
branch : 7.0
---
 modules/account_invoice/invoice.py | 2 ++
 modules/sale_point/sale.py         | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/modules/account_invoice/invoice.py b/modules/account_invoice/invoice.py
index 93fa23fc97..d85075c2e6 100644
--- a/modules/account_invoice/invoice.py
+++ b/modules/account_invoice/invoice.py
@@ -2497,6 +2497,8 @@ class InvoiceLine(sequence_ordered(), ModelSQL, ModelView, TaxableMixin):
             return self.taxes_date
         elif hasattr(self, 'invoice') and hasattr(self.invoice, 'tax_date'):
             return self.invoice.tax_date
+        else:
+            return super().tax_date
 
     def _get_tax_context(self):
         if self.invoice:
diff --git a/modules/sale_point/sale.py b/modules/sale_point/sale.py
index b54cb8c734..cc61413b95 100644
--- a/modules/sale_point/sale.py
+++ b/modules/sale_point/sale.py
@@ -440,7 +440,7 @@ class POSSale(Workflow, ModelSQL, ModelView, TaxableMixin):
 
     @property
     def tax_date(self):
-        return self.date
+        return self.date or super().tax_date
 
 
 class POSSaleLine(ModelSQL, ModelView, TaxableMixin):
@@ -714,7 +714,7 @@ class POSSaleLine(ModelSQL, ModelView, TaxableMixin):
 
     @property
     def tax_date(self):
-        return self.sale.date
+        return self.sale.date or super().tax_date
 
 
 class POSCashSession(Workflow, ModelSQL, ModelView):