[FIX] mrp: date expected and date deadline

- Create Product A:
  Routes: MTO and Manufacture
  Manufacturing Lead Time: 20 days
- Create Product B:
  Routes: MTO and Buy
  Add a supplier with Delivery Lead Time: 10 days
- Create a BOM: 1 unit of B to produce 1 unit of A
- Create a SO for A, validate

A MO is created with a Deadline set at SO order date - 20 days => OK
A PO is created with order date set at SO order date - 10 days => Not
OK, it should be - 30 days.

In v13, the raw materials expected date is the order date.
In v12, this date is computed as: order date minus Manufacturing Lead
Time

However, in both versions the PO order date is computed as the raw
materials expected date minus Delivery Lead Time of the supplier.

This comes from a change in the semantic of 'Planned Date' and 'Planned
End Date'. In v13, the Manufacturing Lead Time is only taken into
account in the Deadline, while in v12 it was taken into account in the
Planned Date. However, the expected date of the raw materials still
relies on the latter, not on the Deadline.

In order to solve this, we apply the 'Manufacturing Lead Time' of the
product and the company to 'Planned Date', 'Planned End Date' and
'Deadline' when the MO is created. Note that the solution is still not
ideal in case no routing is set on the BOM since 'Planned Date' and
'Planned End Date' won't be updated later in the process.

opw-2118951

closes odoo/odoo#40360

X-original-commit: b523f991572e32e69c5f8000a21553191ca54773
Signed-off-by: Nicolas Martinelli (nim) <nim@odoo.com>

addons/mrp/models/stock_rule.py

@@ -74,6 +74,7 @@ class StockRule(models.Model):
         )._bom_find(product=product_id, picking_type=self.picking_type_id, bom_type='normal')  # TDE FIXME: context bullshit
 
     def _prepare_mo_vals(self, product_id, product_qty, product_uom, location_id, name, origin, company_id, values, bom):
+        date_deadline = fields.Datetime.to_string(self._get_date_planned(product_id, company_id, values))
         return {
             'origin': origin,
             'product_id': product_id.id,
@@ -82,9 +83,9 @@ class StockRule(models.Model):
             'location_src_id': self.location_src_id.id or self.picking_type_id.default_location_src_id.id or location_id.id,
             'location_dest_id': location_id.id,
             'bom_id': bom.id,
-            'date_deadline': fields.Datetime.to_string(self._get_date_planned(product_id, company_id, values)),
-            'date_planned_finished': values['date_planned'],
-            'date_planned_start': fields.Datetime.from_string(values['date_planned']) - relativedelta(hours=1),
+            'date_deadline': date_deadline,
+            'date_planned_finished': date_deadline,
+            'date_planned_start': fields.Datetime.from_string(date_deadline) - relativedelta(hours=1),
             'procurement_group_id': False,
             'propagate_cancel': self.propagate_cancel,
             'propagate_date': self.propagate_date,