[FIX] calendar: set correct recurring start_date

A recurring event with a start date and a time duration had a wrong start and
stop date computed.

Introduced at 76b724294a.
Previously the r_date contained only the start_date but now it contains both
start and stop dates. This implies that the method 'get_recurrent_ids' could
use 'get_search_fields' with a stop_date (depending on the domain order) and
returns incorrect dates.

This commit ensure to launch the get_search_fields with the start date.

Closes #15922

addons/calendar/models/calendar.py

@@ -1054,7 +1054,7 @@ class Meeting(models.Model):
 
                 if [True for item in new_pile if not item]:
                     continue
-                result_data.append(meeting.get_search_fields(order_fields, r_date=r_date))
+                result_data.append(meeting.get_search_fields(order_fields, r_date=r_start_date))
 
         if order_fields:
             uniq = lambda it: collections.OrderedDict((id(x), x) for x in it).values()

addons/calendar/tests/test_calendar_recurrent_event_case2.py

@@ -2,6 +2,7 @@
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
 from odoo.tests import common
+from odoo.addons.calendar.models.calendar import calendar_id2real_id
 
 
 class TestRecurrentEvent(common.TransactionCase):
@@ -145,3 +146,26 @@ class TestRecurrentEvent(common.TransactionCase):
             ('start', '>=', '2017-06-30 08:00:00'), ('name', '=', 'Review code with programmer')
         ])
         self.assertEqual(meetings_count, 1, "Last recurrent weekly meetings are not found without stop filter !")
+
+    def test_recurrent_meeting5(self):
+        # I create a recurrent event and I check if the virtual_id are correct
+        self.CalendarEvent.create({
+            'count': 5,
+            'start': '2012-04-13 11:00:00',
+            'stop': '2012-04-13 12:00:00',
+            'duration': 1.0,
+            'name': 'Test Meeting',
+            'recurrency': True,
+            'rrule_type': 'daily'
+        })
+        # I search for the first recurrent meeting
+        meeting = self.CalendarEvent.with_context({'virtual_id': True}).search([
+            ('start', '=', '2012-04-13 11:00:00'), ('stop', '=', '2012-04-13 12:00:00')
+        ])
+        virutal_dates = calendar_id2real_id(meeting.id, with_date=True)
+
+        # virtual_dates are used by the calendar view and I check if the start date for the first virtual event is correct.
+        self.assertEqual(virutal_dates[1], '2012-04-13 11:00:00', "The virtual event doesn't have the correct start date !")
+
+        # virtual_dates are used by the calendar view and I check if the stop date for the first virtual event is correct.
+        self.assertEqual(virutal_dates[2], '2012-04-13 12:00:00', "The virtual event doesn't have the correct stop date !")