[REVERT] sale: Fix fiscal pos. mapping taxes to price included

This reverts commit d89562e.

Since this commit, the taxes mapped by fiscal position wasn't managed by the _fix_tax_included_price_company method anymore.
Otherwise, some customizations exist on this method that are no longer called.
The 2527940 issue is also due to a remaining bug: the total_excluded price should be divided by the quantity but:
- what if the quantity & price_unit are both signed?
- what if the number of digits for price_unit and the currency are different? Should we skip the rounding of taxes?
Since this commit is not perfect and has a lot of dependencies in others modules, we decided to revert it.

Original PR: odoo#68997
Revert PR: odoo#70858

closes odoo#70883

Issue: 2527940
X-original-commit: c9330e4
Signed-off-by: Victor Feyens (vfe) <[email protected]>
Signed-off-by: Laurent Smet <[email protected]>

addons/sale/models/sale.py

@@ -1648,43 +1648,6 @@ def _get_display_price(self, product):
         # negative discounts (= surcharge) are included in the display price
         return max(base_price, final_price)
 
-    def _get_default_price_unit_from_product(self, product):
-        self.ensure_one()
-
-        currency = self.order_id.currency_id
-        fiscal_position = self.order_id.fiscal_position_id or self.order_id.partner_id.property_account_position_id
-        product_taxes = self.product_id.taxes_id.filtered(lambda r: r.company_id == self.order_id.company_id)
-        product_taxes_after_fp = fiscal_position.map_tax(product_taxes, partner=self.order_id.partner_id)
-        price_unit = self._get_display_price(product)
-
-        if set(product_taxes.ids) != set(product_taxes_after_fp.ids):
-            flattened_taxes = product_taxes._origin.flatten_taxes_hierarchy()
-            if any(tax.price_include for tax in flattened_taxes):
-                taxes_res = flattened_taxes.compute_all(
-                    price_unit,
-                    quantity=self.product_uom_qty,
-                    currency=currency,
-                    product=self.product_id,
-                    partner=self.order_id.partner_id,
-                )
-                price_unit = currency.round(taxes_res['total_excluded'])
-
-            flattened_taxes = product_taxes_after_fp._origin.flatten_taxes_hierarchy()
-            if any(tax.price_include for tax in flattened_taxes):
-                taxes_res = flattened_taxes.compute_all(
-                    price_unit,
-                    quantity=self.product_uom_qty,
-                    currency=currency,
-                    product=self.product_id,
-                    partner=self.order_id.partner_id,
-                    handle_price_include=False,
-                )
-                for tax_res in taxes_res['taxes']:
-                    tax = self.env['account.tax'].browse(tax_res['id'])
-                    if tax.price_include:
-                        price_unit += tax_res['amount']
-        return price_unit
-
     @api.onchange('product_id')
     def product_id_change(self):
         if not self.product_id:
@@ -1713,13 +1676,13 @@ def product_id_change(self):
             pricelist=self.order_id.pricelist_id.id,
             uom=self.product_uom.id
         )
+
         vals.update(name=self.get_sale_order_line_multiline_description_sale(product))
 
         self._compute_tax_id()
 
         if self.order_id.pricelist_id and self.order_id.partner_id:
-            vals['price_unit'] = self._get_default_price_unit_from_product(product)
-
+            vals['price_unit'] = self.env['account.tax']._fix_tax_included_price_company(self._get_display_price(product), product.taxes_id, self.tax_id, self.company_id)
         self.update(vals)
 
         title = False
@@ -1752,7 +1715,7 @@ def product_uom_change(self):
                 uom=self.product_uom.id,
                 fiscal_position=self.env.context.get('fiscal_position')
             )
-            self.price_unit = self._get_default_price_unit_from_product(product)
+            self.price_unit = self.env['account.tax']._fix_tax_included_price_company(self._get_display_price(product), product.taxes_id, self.tax_id, self.company_id)
 
     def name_get(self):
         result = []

addons/sale/tests/__init__.py

@@ -12,4 +12,3 @@
 from . import test_sale_signature
 from . import test_sale_transaction
 from . import test_sale_flow
-from . import test_sale_fiscal_position