[FIX] account, purchase: keep the default account of invoice line instead of replacing it to False (happens when the product/product categ is not correctly configured)

addons/account/models/account_invoice.py

@@ -1110,7 +1110,8 @@ class AccountInvoiceLine(models.Model):
 
             self.name = product.partner_ref
             account = self.get_invoice_line_account(type, product, fpos, company)
-            self.account_id = account.id
+            if account:
+                self.account_id = account.id
             self._set_taxes()
 
             if type in ('in_invoice', 'in_refund'):

addons/purchase/invoice.py

@@ -42,22 +42,25 @@ class AccountInvoice(models.Model):
                 qty = line.qty_received - line.qty_invoiced
             if float_compare(qty, 0.0, precision_rounding=line.product_uom.rounding) <= 0:
                 qty = 0.0
-            account = self.env['account.invoice.line'].get_invoice_line_account('in_invoice', line.product_id, self.purchase_id.fiscal_position_id, self.env.user.company_id)
             taxes = line.taxes_id or line.product_id.supplier_taxes_id
             invoice_line_tax_ids = self.purchase_id.fiscal_position_id.map_tax(taxes)
-            result.append({
+            data = {
                 'purchase_line_id': line.id,
                 'name': line.name,
                 'origin': self.purchase_id.origin,
                 'uom_id': line.product_uom.id,
                 'product_id': line.product_id.id,
-                'account_id': account.id,
+                'account_id': self.env['account.invoice.line'].with_context({'journal_id': self.journal_id.id, 'type': 'in_invoice'})._default_account(),
                 'price_unit': line.price_unit,
                 'quantity': qty,
                 'discount': 0.0,
                 'account_analytic_id': line.account_analytic_id.id,
                 'invoice_line_tax_ids': invoice_line_tax_ids.ids
-            })
+            }
+            account = self.env['account.invoice.line'].get_invoice_line_account('in_invoice', line.product_id, self.purchase_id.fiscal_position_id, self.env.user.company_id)
+            if account:
+                data['account_id'] = account.id
+            result.append(data)
         self.invoice_line_ids = result
         return {}