No property change from ‘org-clock-sum’

[Ben Finney <ben+emacs@benfinney.id.au>]

Howdy all,

When I use ‘org-clock-sum’ in Org-mode version 7.4, nothing appears to
happen: the items in the subtree are not updated and no ‘CLOCKSUM’
property appears.


I'm trying to generate an invoice report using ‘org-invoice.el’.

The items on which I want to report have clock entries, generated
correctly with ‘org-clock-in’ and ‘org-clock-out’. An example:

=====
* foo
** bar
*** [2011-03-24 Thu]
    CLOCK: [2011-03-24 Thu 14:15]--[2011-03-24 Thu 18:03] =>  3:48
    CLOCK: [2011-03-24 Thu 09:10]--[2011-03-24 Thu 12:27] =>  3:17
*** [2011-03-23 Wed]
    CLOCK: [2011-03-23 Wed 14:10]--[2011-03-23 Wed 18:16] =>  4:06
    CLOCK: [2011-03-23 Wed 09:30]--[2011-03-23 Wed 13:10] =>  3:40
*** [2011-03-22 Tue]
    CLOCK: [2011-03-22 Tue 14:00]--[2011-03-22 Tue 17:30] =>  3:30
    CLOCK: [2011-03-22 Tue 08:58]--[2011-03-22 Tue 13:31] =>  4:33
=====

According to the doc string for ‘org-invoice-report’, the ‘CLOCKSUM’
property on each item in the subtree will be used for the report.

So apparently I need to ‘org-clock-sum’ on the tree before updating the
report, in order to automatically generate the ‘CLOCKSUM’ property. But
that function doesn't change anything.

Why wouldn't the ‘org-clock-sum’ function do what its doc string says?
How should I be updating the ‘CLOCKSUM’ property?

-- 
 \         “Pinky, are you pondering what I'm pondering?” “I think so, |
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Ben Finney