[Chandler-dev] Re: about pure occurrences

[Grant Baillie]

On 30 Mar, 2007, at 09:16, Andi Vajda wrote:

>
> On Fri, 30 Mar 2007, Jeffrey Harris wrote:
>
>>> Digging a little further, I see that *all* occurrences created when
>>> importing an .ics file or restoring cosmo collections are impure,  
>>> they
>>> all have a non None value for 'modificationFor'. The only time I was
>>> able to create pure occurrences was by scrolling the calendar  
>>> back and
>>> forth by some weeks.
>>>
>>> Is it expected that all imported occurrences have a  
>>> 'modificationFor'
>>> value ?
>>
>> Yup, that's roughly the expected behavior.  The main time that
>> unmodified occurrences get created is in the calendar view.
>
> Why is that ? What is the modification that makes these impure ?
> If that could be changed, I'd expect some serious performance  
> improvements...

Import has no reason to create "pure" (a.k.a. trivial) occurrences. I  
haven't looked at what happens in the auto-triage world, but  
importing a single master event should create at most 3 modifications  
(for NOW/LATER/DONE, where applicable), and no "pure" occurrences.  
One way to see if this is the case is to import a calendar containing  
1 recurring event, and see how many times  
EventStamp._createOccurrence is called.

--Grant

PS: As an aside, when fixing Bug 8472 this week, things were out-of- 
whack in such a way that the return value of _createOccurrence() was  
not be stored in the master's inheritTo reflist. Needless to say,  
this caused (amongst other things) a "leak" in the calendar.