[FIX] calendar: event recurrence start date is not correctly computed

Steps to follow:

  - Set your timezone to New York
    In linux for example with: `timedatectl set-timezone America/New_York`
  - Verify that the user timezone is also set to NY
  - Create a reccurent event the 6 july 2022 (a wednesday)
  - In options, check the recurrent box
  - Set repeat to once every week
  - Thursday is the only day checked
  -> It should be Wednesday

Cause of the issue:

  When `_compute_recurrence` is called, `event.recurrence_id` has not
  yet been set
  -> `event.recurrence_id.event_tz` is False
  => Copy the defaults before computing the start date and check the
  timezone of the event itself

opw-2886253

closes odoo/odoo#96049

X-original-commit: 7186dbad38ef1f05919c398f3c0c5f5d8f8b2219
Signed-off-by: Arnaud Joset <arj@odoo.com>
Signed-off-by: Hubert Van De Walle <huvw@odoo.com>

addons/calendar/models/calendar_event.py

@@ -352,13 +352,14 @@ class Meeting(models.Model):
         defaults = self.env['calendar.recurrence'].default_get(recurrence_fields)
         for event in self:
             if event.recurrency:
+                event.update(defaults)  # default recurrence values are needed to correctly compute the recurrence params
                 event_values = event._get_recurrence_params()
                 rrule_values = {
                     field: event.recurrence_id[field]
                     for field in recurrence_fields
                     if event.recurrence_id[field]
                 }
-                event.update({**false_values, **defaults, **event_values, **rrule_values})
+                event.update({**false_values, **event_values, **rrule_values})
             else:
                 event.update(false_values)
 
@@ -1082,8 +1083,8 @@ class Meeting(models.Model):
         """
         if not self.start:
             return fields.Date.today()
-        if self.recurrence_id.event_tz:
-            tz = pytz.timezone(self.recurrence_id.event_tz)
+        if self.recurrency and self.event_tz:
+            tz = pytz.timezone(self.event_tz)
             # Ensure that all day events date are not calculated around midnight. TZ shift would potentially return bad date
             start = self.start if not self.allday else self.start.replace(hour=12)
             return pytz.utc.localize(start).astimezone(tz).date()

addons/calendar/tests/test_calendar.py

@@ -5,6 +5,7 @@ import datetime
 from datetime import datetime, timedelta, time
 
 from odoo import fields, Command
+from odoo.tests import Form
 from odoo.addons.base.tests.common import SavepointCaseWithUserDemo
 import pytz
 import re
@@ -186,6 +187,14 @@ class TestCalendar(SavepointCaseWithUserDemo):
                 self.assertEqual(d.hour, 15)
             self.assertEqual(d.minute, 30)
 
+    def test_recurring_ny(self):
+        self.env.user.tz = 'US/Eastern'
+        f = Form(self.CalendarEvent.with_context(tz='US/Eastern'))
+        f.name = 'test'
+        f.start = '2022-07-07 01:00:00'  # This is in UTC. In NY, it corresponds to the 6th of july at 9pm.
+        f.recurrency = True
+        self.assertEqual(f.weekday, 'WED')
+
     def test_event_activity_timezone(self):
         activty_type = self.env['mail.activity.type'].create({
             'name': 'Meeting',