[FIX] hr_holidays : deduct correct # days on allocation

Steps :
Create, confirm and validate 2 overlapping leave allocations :
	> Type : T
	> Duration : 5 days
Create, confirm and approve a time off request in the overlapping period :
	> Type : T
	> Duration : 10 days
Go to the allocations.

Issue :
They have respectively 0 and 10 days taken.

Cause :
hr_leave.holiday_allocation_id is m2o, so 2 allocations cannot be
attributed to the same leave request.
_compute_from_holiday_status_id() sets the first valid (in terms of
validity dates) allocation to this field, without comparing the
number of leave days of the allocation and the request.

Fix :
Compare it. If no allocation has sufficient number of days, but their
sum is enough, ask the user to split them.

opw-2781530

closes odoo/odoo#87468

X-original-commit: a0ff3fc5888d8b6a794d40d32b2a546761dfa791
Signed-off-by: Kevin Baptiste <kba@odoo.com>

addons/hr_holidays/i18n/hr_holidays.pot

@@ -4058,6 +4058,14 @@ msgid ""
 "You don't have the rights to apply second approval on a time off request"
 msgstr ""
 
+#. module: hr_holidays
+#: code:addons/hr_holidays/models/hr_leave.py:0
+#, python-format
+msgid ""
+"You have several allocations for those type and period.\n"
+"Please split your request to fit in their number of days."
+msgstr ""
+
 #. module: hr_holidays
 #: code:addons/hr_holidays/models/hr_leave.py:0
 #, python-format

addons/hr_holidays/models/hr_leave.py

@@ -302,6 +302,12 @@ class HolidaysRequest(models.Model):
         for leave in self:
             leave.all_employee_ids = leave.employee_id | leave.employee_ids
 
+    @api.constrains('holiday_status_id', 'number_of_days')
+    def _check_allocation_duration(self):
+        for holiday in self:
+            if holiday.holiday_status_id.requires_allocation == 'yes' and holiday.number_of_days > holiday.holiday_allocation_id.number_of_days:
+                raise ValidationError(_("You have several allocations for those type and period.\nPlease split your request to fit in their number of days."))
+
     @api.depends_context('uid')
     def _compute_description(self):
         self.check_access_rights('read')
@@ -355,7 +361,7 @@ class HolidaysRequest(models.Model):
                 '&',
                 ('date_to', '=', False),
                 ('date_from', '<=', max(self.mapped('date_from'))),
-            ], ['id', 'date_from', 'date_to', 'holiday_status_id', 'employee_id'], order="date_to, id"
+            ], ['id', 'date_from', 'date_to', 'holiday_status_id', 'employee_id', 'number_of_days'], order="number_of_days desc, date_to, id"
         )
         allocations_dict = defaultdict(lambda: [])
         for allocation in allocations:

addons/hr_holidays/tests/test_leave_requests.py

@@ -583,3 +583,49 @@ class TestLeaveRequests(TestHrHolidaysCommon):
             'date_to': datetime(2022, 3, 11, 23, 59, 59),
         })
         self.assertEqual(leave.number_of_days, 1)
+
+    def test_several_allocations(self):
+        allocation_vals = {
+            'name': 'Allocation',
+            'employee_id': self.employee_emp_id,
+            'holiday_status_id': self.holidays_type_2.id,
+            'number_of_days': 5,
+            'state': 'confirm',
+            'date_from': '2022-01-01',
+            'date_to': '2022-12-31',
+        }
+        allocation1 = self.env['hr.leave.allocation'].create(allocation_vals)
+        allocation2 = self.env['hr.leave.allocation'].create(allocation_vals)
+
+        allocation1.action_validate()
+        allocation2.action_validate()
+
+        # Neither allocation has enough days
+        with self.assertRaises(ValidationError):
+            self.env['hr.leave'].with_user(self.user_employee_id).create({
+                'name': 'Holiday Request',
+                'employee_id': self.employee_emp_id,
+                'holiday_status_id': self.holidays_type_2.id,
+                'date_from': '2022-01-01',
+                'date_to': '2022-01-15',
+                'number_of_days': 10,
+            })
+
+        allocation_vals.update({'number_of_days': 10})
+        allocation3 = self.env['hr.leave.allocation'].create(allocation_vals)
+        allocation3.action_validate()
+
+        # The 3rd allocation has enough days, so it should be picked
+        holiday = self.env['hr.leave'].with_user(self.user_employee_id).create({
+            'name': 'Holiday Request',
+            'employee_id': self.employee_emp_id,
+            'holiday_status_id': self.holidays_type_2.id,
+            'date_from': '2022-01-01',
+            'date_to': '2022-01-15',
+            'number_of_days': 10,
+        })
+        holiday.sudo().action_validate()
+
+        self.assertEqual(allocation1.leaves_taken, 0.0, 'As this allocation does not have enough days, it should not be affected')
+        self.assertEqual(allocation2.leaves_taken, 0.0, 'As this allocation does not have enough days, it should not be affected')
+        self.assertEqual(allocation3.leaves_taken, 10.0, 'As this allocation has enough days, the leave days should be taken')