Add option on employees to exclude from mass allocation

hr_holidays_usability/hr_employee_view.xml

@@ -12,9 +12,16 @@
     <field name="model">hr.employee</field>
     <field name="inherit_id" ref="hr_holidays.view_employee_form_leave_inherit"/>
     <field name="arch" type="xml">
+        <!-- too difficult to hide the inside of the Leave group
+        so I hide the whole group and re-create one -->
         <group string="Leaves" position="attributes">
             <attribute name="invisible">1</attribute>
         </group>
+        <group string="Leaves" position="after">
+            <group name="holidays" string="Holidays">
+                <field name="holiday_exclude_mass_allocation"/>
+            </group>
+        </group>
     </field>
 </record>
 

hr_holidays_usability/hr_holidays.py

@@ -41,6 +41,13 @@ class HrHolidaysStatus(models.Model):
         default='worked')
 
 
+class HrEmployee(models.Model):
+    _inherit = 'hr.employee'
+
+    holiday_exclude_mass_allocation = fields.Boolean(
+        string='Exclude from Mass Holiday Attribution')
+
+
 class HrHolidays(models.Model):
     _inherit = 'hr.holidays'
     _order = 'type desc, date_from desc'

hr_holidays_usability/wizard/hr_holidays_mass_allocation.py

@@ -29,8 +29,9 @@ class HrHolidaysMassAllocation(models.TransientModel):
     _description = 'Wizard for mass allocation of holidays'
 
     @api.model
-    def _get_all_employees(self):
-        return self.env['hr.employee'].search([])
+    def _default_employees(self):
+        return self.env['hr.employee'].search([
+            ('holiday_exclude_mass_allocation', '=', False)])
 
     @api.model
     def _get_default_holiday_status(self):
@@ -44,7 +45,7 @@ class HrHolidaysMassAllocation(models.TransientModel):
         'hr.holidays.status', string='Leave Type', required=True,
         default=_get_default_holiday_status)
     employee_ids = fields.Many2many(
-        'hr.employee', string='Employees', default=_get_all_employees)
+        'hr.employee', string='Employees', default=_default_employees)
     auto_approve = fields.Boolean(
         string='Automatic Approval', default=True)
     # size=64 because the name field of hr.holidays is size=64