[FIX] project_timesheet_holidays: Fix traceback when no timesheet_task_id is found.

-steps to reproduce:
 do a search in project.task on is_timeoff_task when no
 timesheet_task_id is defined on any hr.leave_type.
 This will trigger the _search_is_timeoff_task method

-before this commit:
 crash when no leave_type with timesheet_task_id is found

-after this commit:
 creation of an empty list as expected

opw-3086486

closes odoo/odoo#110091

X-original-commit: b98949b1cb85514ee5a56ff1a5860591c10b0994
Signed-off-by: Xavier Bol (xbo) <xbo@odoo.com>

addons/project_timesheet_holidays/models/project_task.py

@@ -32,7 +32,7 @@ class Task(models.Model):
             ['timesheet_task_ids:array_agg(timesheet_task_id)'],
             [],
         )
-        timeoff_task_ids = leave_type_read_group[0]['timesheet_task_ids'] if leave_type_read_group else []
+        timeoff_task_ids = leave_type_read_group[0]['timesheet_task_ids'] if leave_type_read_group[0]['timesheet_task_ids'] else []
         if self.env.company.leave_timesheet_task_id:
             timeoff_task_ids.append(self.env.company.leave_timesheet_task_id.id)
         if operator == '!=':

addons/project_timesheet_holidays/tests/test_timesheet_global_time_off.py

@@ -175,3 +175,12 @@ class TestTimesheetGlobalTimeOff(common.TransactionCase):
         # The standard calendar is for 8 hours/day from 8 to 12 and from 13 to 17.
         # So we need to check that the timesheets don't have more than 8 hours per day.
         self.assertEqual(leave_task.effective_hours, 80)
+
+    def test_search_is_timeoff_task(self):
+        """ Test the search method on is_timeoff_task
+        with and without any hr.leave.type with timesheet_task_id defined"""
+        leaves_types_with_task_id = self.env['hr.leave.type'].search([('timesheet_task_id', '!=', False)])
+        self.env['project.task'].search([('is_timeoff_task', '!=', False)])
+
+        leaves_types_with_task_id.write({'timesheet_task_id': False})
+        self.env['project.task'].search([('is_timeoff_task', '!=', False)])