[FIX] resource: Find intervals in the resource timezone

With a user with timezone "Europe/Brussels", add a
slot on the gantt view where the preceding day is a working day.
The default starting time will be the previous day.
Reason: the default starting time is midnight, adjusted to
the closest attendance interval in the employee's calendar.
However, midnight in "Europe/Brussels" is actually 10pm UTC
the previous day.
The method adjusting the datetime to the closest attendance only
checks within the corresponding day.

Two ways to fix this:
1) the business code calling `_adjust_to_calendar` should
   timezone the datetimes itself. To avoid similar bugs in the future,
   the method should be modified to only accept timezoned datetimes.

2) Change `_adjust_to_calendar` to convert datetimes it was given
   to the resource's timezone and consider the dates in those converted
   datetimes.

Option 2 is chosen because it seems to take care of the problem at a lower
level which allows the business code to not think about those timezone details.
While this is technically an API change (in a stable release), the method was
introduced recently by b058ca1 as a fix for an already broken method.

closes odoo/odoo#53582

X-original-commit: c6cecac60360a1d8b0c62ee155a818a3a28505e1
Related: odoo/enterprise#11399
Signed-off-by: Yannick Tivisse (yti) <yti@odoo.com>

addons/resource/models/resource.py

@@ -3,7 +3,6 @@
 
 from collections import defaultdict
 import math
-import logging
 from datetime import datetime, time, timedelta
 from dateutil.relativedelta import relativedelta
 from dateutil.rrule import rrule, DAILY, WEEKLY
@@ -20,8 +19,6 @@ from odoo.tools.float_utils import float_round
 from odoo.tools import date_utils, float_utils
 from .resource_mixin import timezone_datetime
 
-_logger = logging.getLogger(__name__)
-
 # Default hour per day value. The one should
 # only be used when the one from the calendar
 # is not available.
@@ -475,15 +472,16 @@ class ResourceCalendar(models.Model):
         def interval_dt(interval):
             return interval[1 if match_end else 0]
 
+        if not dt.tzinfo or search_range and not (search_range[0].tzinfo and search_range[1].tzinfo):
+            raise ValueError('Provided datetimes needs to be timezoned')
+        dt = dt.astimezone(timezone(self.tz))
+
         if not search_range:
             range_start = dt + relativedelta(hour=0, minute=0, second=0)
             range_end = dt + relativedelta(days=1, hour=0, minute=0, second=0)
         else:
             range_start, range_end = search_range
 
-        if not (dt.tzinfo and range_start.tzinfo and range_end.tzinfo):
-            raise ValueError('Provided datetimes needs to be timezoned')
-
         if not range_start <= dt <= range_end:
             return None
         work_intervals = sorted(
@@ -778,7 +776,8 @@ class ResourceResource(models.Model):
         for resource in self:
             calendar_start = resource.calendar_id._get_closest_work_time(start, resource=resource)
             search_range = None
-            if calendar_start and start.date() == end.date():
+            tz = timezone(resource.tz)
+            if calendar_start and start.astimezone(tz).date() == end.astimezone(tz).date():
                 # Make sure to only search end after start
                 search_range = (
                     start,

addons/resource/tests/test_resource.py

@@ -438,6 +438,10 @@ class TestCalendar(TestResourceCommon):
         calendar_dt = self.calendar_john._get_closest_work_time(dt, resource=self.john.resource_id)
         self.assertEqual(calendar_dt, start, "It should have taken john's specific attendances")
 
+        dt = datetime_tz(2020, 4, 4, 1, 0, 0, tzinfo='UTC')  # The next day in UTC, but still the 3rd in john's timezone (America/Los_Angeles)
+        start = datetime_tz(2020, 4, 3, 16, 0, 0, tzinfo=self.john.tz)
+        calendar_dt = self.calendar_john._get_closest_work_time(dt, resource=self.john.resource_id)
+        self.assertEqual(calendar_dt, start, "It should have found the attendance on the 3rd April")
 
 class TestResMixin(TestResourceCommon):
 
@@ -487,6 +491,21 @@ class TestResMixin(TestResourceCommon):
             datetime_tz(2020, 4, 3, 13, 0, 0, tzinfo=self.john.tz),
         ))
 
+    def test_adjust_calendar_timezone_after(self):
+        # Calendar:
+        # Tuesdays 8-16
+        # Fridays 8-13 and 16-23
+        tz = 'Europe/Brussels'
+        self.john.tz = tz
+        result = self.john._adjust_to_calendar(
+            datetime(2020, 4, 2, 23, 0, 0),  # The previous day in UTC, but the 3rd in Europe/Brussels
+            datetime(2020, 4, 3, 20, 0, 0),
+        )
+        self.assertEqual(result[self.john], (
+            datetime(2020, 4, 3, 6, 0, 0),
+            datetime(2020, 4, 3, 21, 0, 0),
+        ), "It should have found a starting time the 3rd")
+
     def test_work_days_data(self):
         # Looking at Jean's calendar