[FIX] mrp: domain on field final_lot_id in mrp.production.work.order.form

Steps to reproduce the bug:

Let's consider two storable products P1 and P2 where P1 is tracked by serial number
- Create a BOM B  for P1 where P2 is a component
- Create a serial numberv SN for P1 with no quantity
- Create a MO M1 for P1 and click on button "Produce"
- In the view MRP Product Produce, SN is selectable in the field lot_id
- Now change B and set a routing on it
- Create a new MO M2 for P1 and click on produce
- At least one WO has been created, click on the first one

Bug:

- SN is not selectable in the field final_lot_id

The domain set on the field final_lot_id:

"['|', '&', ('product_id', '=', product_id), ('product_id.tracking', '!=', 'serial'), ('use_next_on_work_order_id', '=', id)]"

didn't allow to chose SN.

With this fix, it's now possible to chose SN on the first WO created for M2

opw:2059745

closes odoo/odoo#36425

Signed-off-by: Simon Goffin (sig) <sig@openerp.com>

addons/mrp/models/mrp_workorder.py

@@ -63,6 +63,9 @@ class MrpWorkorder(models.Model):
     is_produced = fields.Boolean(string="Has Been Produced",
         compute='_compute_is_produced')
 
+    is_first_wo = fields.Boolean(string="Is the first WO to produce",
+        compute='_compute_is_first_wo')
+
     state = fields.Selection([
         ('pending', 'Pending'),
         ('ready', 'Ready'),
@@ -140,6 +143,11 @@ class MrpWorkorder(models.Model):
         rounding = self.production_id.product_uom_id.rounding
         self.is_produced = float_compare(self.qty_produced, self.production_id.product_qty, precision_rounding=rounding) >= 0
 
+    @api.multi
+    def _compute_is_first_wo(self):
+        for wo in self:
+            wo.is_first_wo = (wo.production_id.workorder_ids[0] == wo)
+
     @api.one
     @api.depends('time_ids.duration', 'qty_produced')
     def _compute_duration(self):

addons/mrp/views/mrp_workorder_views.xml

@@ -141,7 +141,8 @@
                     <group>
                         <group>
                             <field name="qty_producing" string="Current Qty" attrs="{'readonly': ['|', ('product_tracking', '=', 'serial'), ('state', 'in', ('done', 'cancel'))]}"/>
-                            <field name="final_lot_id" context="{'default_product_id': product_id}" domain="['|', '&amp;', ('product_id', '=', product_id), ('product_id.tracking', '!=', 'serial'), ('use_next_on_work_order_id', '=', id)]" attrs="{'invisible': [('product_tracking', '=', 'none')]}" groups="stock.group_production_lot"/>
+                            <field name='is_first_wo' invisible="1"/>
+                            <field name="final_lot_id" context="{'default_product_id': product_id}" domain="['|', '&amp;', ('product_id', '=', product_id), '|', ('product_id.tracking', '!=', 'serial'), '&amp;', ('use_next_on_work_order_id', '=', False), ('use_next_on_work_order_id', '!=', 'is_first_wo'), ('use_next_on_work_order_id', '=', id)]" attrs="{'invisible': [('product_tracking', '=', 'none')]}" groups="stock.group_production_lot"/>
                             <field name="product_tracking" invisible="1"/>
                         </group>
                     </group>