[FIX] hr_holidays: make _onchange_request_parameters handle timezones

At the end it constructs date_{from,to} (Datetime) by combining:

- request_date_{from,to} (Date) local to the user
- UTC time from date_{from,to} (extracted using time() into hour_{from,to})

This doesn't work in all cases, e.g.:

A leave in US/Pacific for one day (with request_unit_custom = True):
- request_date_from: 1st of Jan
- request_date_to:   1st of Jan
- hour_from:         15:00 (7:00 local)
- hour_to:           03:00 (19:00 local) <-- this happens on the 2nd of Jan in UTC

Before this patch it resulted in:
date_from: 1st of Jan 15:00
date_to:   1st of Jan 03:00

The correct value for date_to is:
date_to:   2nd of Jan 03:00

_adjust_date_based_on_tz takes care of adjusting the date based on the
hour and the user's timezone.

opw-2169863

closes odoo/odoo#44534

closes odoo/odoo#45746

X-original-commit: 523fd6e3c4ea3a4c153616bf6bdba9573501127f
Original-signed-off-by: jorenvo <jorenvo@users.noreply.github.com>
Signed-off-by: Nicolas Martinelli (nim) <nim@odoo.com>

2 files changed, 74 insertions, 16 deletions

diff --git a/addons/hr_holidays/models/hr_leave.py b/addons/hr_holidays/models/hr_leave.py
index fb97d73eb84..a63fd51641e 100644
--- a/addons/hr_holidays/models/hr_leave.py
+++ b/addons/hr_holidays/models/hr_leave.py
@@ -8,7 +8,7 @@ import math
 
 from collections import namedtuple
 
-from datetime import datetime, time
+from datetime import datetime, date, timedelta, time
 from dateutil.rrule import rrule, DAILY
 from pytz import timezone, UTC
 
@@ -356,6 +356,9 @@ class HolidaysRequest(models.Model):
             # find last attendance coming before last_day
             attendance_to = next((att for att in reversed(attendances) if int(att.dayofweek) <= self.request_date_to.weekday()), attendances[-1] if attendances else default_value)
 
+        compensated_request_date_from = self.request_date_from
+        compensated_request_date_to = self.request_date_to
+
         if self.request_unit_half:
             if self.request_date_from_period == 'am':
                 hour_from = float_to_time(attendance_from.hour_from)
@@ -369,12 +372,15 @@ class HolidaysRequest(models.Model):
         elif self.request_unit_custom:
             hour_from = self.date_from.time()
             hour_to = self.date_to.time()
+            compensated_request_date_from = self._adjust_date_based_on_tz(self.request_date_from, hour_from)
+            compensated_request_date_to = self._adjust_date_based_on_tz(self.request_date_to, hour_to)
         else:
             hour_from = float_to_time(attendance_from.hour_from)
             hour_to = float_to_time(attendance_to.hour_to)
 
-        self.date_from = timezone(self.tz).localize(datetime.combine(self.request_date_from, hour_from)).astimezone(UTC).replace(tzinfo=None)
-        self.date_to = timezone(self.tz).localize(datetime.combine(self.request_date_to, hour_to)).astimezone(UTC).replace(tzinfo=None)
+        self.date_from = timezone(self.tz).localize(datetime.combine(compensated_request_date_from, hour_from)).astimezone(UTC).replace(tzinfo=None)
+        self.date_to = timezone(self.tz).localize(datetime.combine(compensated_request_date_to, hour_to)).astimezone(UTC).replace(tzinfo=None)
+
         self._onchange_leave_dates()
 
     @api.onchange('request_unit_half')
@@ -571,6 +577,28 @@ class HolidaysRequest(models.Model):
 
         return {'days': hours / (today_hours or HOURS_PER_DAY), 'hours': hours}
 
+    def _adjust_date_based_on_tz(self, leave_date, hour):
+        """ request_date_{from,to} are local to the user's tz but hour_{from,to} are in UTC.
+
+        In some cases they are combined (assuming they are in the same tz) as a datetime. When
+        that happens it's possible we need to adjust one of the dates. This function adjust the
+        date, so that it can be passed to datetime().
+
+        E.g. a leave in US/Pacific for one day:
+        - request_date_from: 1st of Jan
+        - request_date_to:   1st of Jan
+        - hour_from:         15:00 (7:00 local)
+        - hour_to:           03:00 (19:00 local) <-- this happens on the 2nd of Jan in UTC
+        """
+        user_tz = timezone(self.env.user.tz if self.env.user.tz else 'UTC')
+        request_date_to_utc = UTC.localize(datetime.combine(leave_date, hour)).astimezone(user_tz).replace(tzinfo=None)
+        if request_date_to_utc.date() < leave_date:
+            return leave_date + timedelta(days=1)
+        elif request_date_to_utc.date() > leave_date:
+            return leave_date - timedelta(days=1)
+        else:
+            return leave_date
+
     ####################################################
     # ORM Overrides methods
     ####################################################
diff --git a/addons/hr_holidays/tests/test_leave_requests.py b/addons/hr_holidays/tests/test_leave_requests.py
index a0cbcc0c79f..fd9652d6d9a 100644
--- a/addons/hr_holidays/tests/test_leave_requests.py
+++ b/addons/hr_holidays/tests/test_leave_requests.py
@@ -2,6 +2,7 @@
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 from datetime import datetime, date
 from dateutil.relativedelta import relativedelta
+from pytz import timezone, UTC
 
 from odoo import fields
 from odoo.exceptions import ValidationError
@@ -366,23 +367,52 @@ class TestLeaveRequests(TestHrHolidaysCommon):
         leave1.action_validate()
         self.assertEqual(leave1.number_of_hours_display, 24)
 
-    @mute_logger('odoo.models.unlink', 'odoo.addons.mail.models.mail_mail')
-    def test_leave_defaults_with_timezones(self):
-        """ Make sure that leaves start with correct defaults for non-UTC timezones """
-        self.user_employee.tz = 'US/Pacific'
+    def _test_leave_with_tz(self, tz, local_date_from, local_date_to, number_of_days):
+        self.user_employee.tz = tz
+        tz = timezone(tz)
 
         # Mimic what is done by the calendar widget when clicking on a day. It
         # will take the local datetime from 7:00 to 19:00 and then convert it
         # to UTC before sending it. Values here are for PST (UTC -8) and
         # represent a leave on 2019/1/1 from 7:00 to 19:00 local time.
-        webclient_values = {
-            'date_from': datetime(2019, 1, 1, 15, 0, 0),
-            'date_to': datetime(2019, 1, 2, 3, 0), # note that this is the next day in UTC
+        values = {
+            'date_from': tz.localize(local_date_from).astimezone(UTC).replace(tzinfo=None),
+            'date_to': tz.localize(local_date_to).astimezone(UTC).replace(tzinfo=None),  # note that this can be the next day in UTC
         }
-        values = self.env['hr.leave'].sudo(self.user_employee_id)._default_get_request_parameters(webclient_values)
+        values.update(self.env['hr.leave'].with_user(self.user_employee_id)._default_get_request_parameters(values))
+
+        # Dates should be local to the user
+        self.assertEqual(values['request_date_from'], local_date_from.date())
+        self.assertEqual(values['request_date_to'], local_date_to.date())
+
+        values.update({
+            'name': 'Test',
+            'employee_id': self.employee_emp_id,
+            'holiday_status_id': self.holidays_type_1.id,
+        })
+        leave = self.env['hr.leave'].with_user(self.user_employee_id).new(values)
+        leave._onchange_request_parameters()
+        self.assertEqual(leave.number_of_days, number_of_days)
 
-        # Dates should be local to the user, they do not and cannot be
-        # converted using the user's timezone.
-        first_of_january = date(2019, 1, 1)
-        self.assertEqual(values['request_date_from'], first_of_january)
-        self.assertEqual(values['request_date_to'], first_of_january)
+    @mute_logger('odoo.models.unlink', 'odoo.addons.mail.models.mail_mail')
+    def test_leave_defaults_with_timezones(self):
+        """ Make sure that leaves start with correct defaults for non-UTC timezones """
+        timezones_to_test = ('UTC', 'Pacific/Midway', 'US/Pacific', 'Asia/Taipei', 'Pacific/Kiritimati')  # UTC, UTC -11, UTC -8, UTC +8, UTC +14
+
+        #     January 2020
+        # Su Mo Tu We Th Fr Sa
+        #           1  2  3  4
+        #  5  6  7  8  9 10 11
+        # 12 13 14 15 16 17 18
+        # 19 20 21 22 23 24 25
+        # 26 27 28 29 30 31
+        local_date_from = datetime(2019, 1, 1, 7, 0, 0)
+        local_date_to = datetime(2019, 1, 1, 19, 0, 0)
+        for tz in timezones_to_test:
+            self._test_leave_with_tz(tz, local_date_from, local_date_to, 1)
+
+        # We, Th, Fr, Mo, Tu, We => 6 days
+        local_date_from = datetime(2019, 1, 1, 7, 0, 0)
+        local_date_to = datetime(2019, 1, 8, 19, 0, 0)
+        for tz in timezones_to_test:
+            self._test_leave_with_tz(tz, local_date_from, local_date_to, 6)