555143 - Sometime first slot in free-busy grid shows as busy if actually it is free, but previous one is busy.

Status: NEW

(Calendar :: Dialogs, defect)

Description

[Irina Arkhipets]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; ru; rv:1.9.1.3) Gecko/20090824 Firefox/3.5.3
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.18pre) Gecko/20080917 Sunbird/0.9

It seems like Mozilla Sunbird shows first time slot in "Invite Attendees" window incorrectly if previous hour is busy, but the first one is actually free.

I was able to reproduce it in several different timezones.

Reproducible: Always

Steps to Reproduce:
We are implementing our own version of Caldav Server, so I am finding difficulty in providing exact steps how to reproduce the failure. Here is just a brief description how I get such results and why I think the problem is in the Mozilla code:

"Day starts at" property of my Mozilla Sunbird is set 9:00 AM

"Day ends at" property of my Mozilla Sunbird is set 6:00 PM

I have subscribed to Caldav calendar which has three meetings – the first starts on 27-Mar-2010 at 4:00 AM and lasts 1 hour, the second starts on 27-Mar-2010 at 4:00 PM and lasts 1 hour, and the third starts on 27-Mar-2010 at 8:00 and lasts 1 hour. Both these meetings has one guest named MyGuest

If  I open any of these meetings and click the "Invite Attendees" button, my Caldav Server get similar free-busy requests from the client. They differ by DTSTAMP values only and look like the following:

…
BEGIN:VCALENDAR
PRODID:-//Mozilla.org/NONSGML Mozilla Calendar V1.1//EN
VERSION:2.0
METHOD:REQUEST
BEGIN:VFREEBUSY
DTSTAMP:20100326T054800Z
ORGANIZER:mailto:[e-mail]
DTSTART:20100326T180000Z
DTEND:20100411T180000Z
UID:9a21660e-a735-40ab-ae4e-02f79f76e35e
ATTENDEE;PARTSTAT=NEEDS-ACTION;ROLE=REQ-PARTICIPANT;CUTYPE=INDIVIDUAL:mailto:[e-mail]
END:VFREEBUSY
END:VCALENDAR
…

Particularly, requests for both these meetings contain exactly the same ATTENDEE, ORGANIZER, DTSTART and DTEND fields. 

Actual Results:  
Apparently, my server sends identical replies for such requests: there are three busy hours there: 4:00-5:00 AM, 8:00-9:00 AM and 4:00-5:00 PM.
But result free busy grids differ: one for the meeting started at 4:00 PM shows time from 9:00 AM to 10:00 AM as busy whereas grids for another meetings show the same hour as free.


Expected Results:  
9:00 AM - 10:00 AM slot in free-busy grid should be shown as free for any meeting.

Comment 1

[Philipp Kewisch [:Fallen] [:📆][:🧩]]

Does this still happen with the latest 1.0b2pre nightlies of Lightning?

Comment 2

[Irina Arkhipets]

Yes, this is also reproducible in the recent Sunbird nightly debelopmen build:

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.10pre) Gecko/20100328 Calendar/1.0b2pre