time-warping - retroactively marking DONE?

[Adam Spiers <orgmode@adamspiers.org>]

Hi all,

I'm looking for a way to retroactively mark a task as having been done
at a previous time/date.  I know that I can just change the keyword to
DONE and then edit the timestamp, but this is tedious when it's a
repeating event, e.g.:

*** NEXT [#A] meditate 15 minutes every day
       SCHEDULED: <2020-07-06 Mon 11:30-11:50 .+1d>
       :PROPERTIES:
       :LAST_REPEAT: [2020-07-05 Sun 11:13]
       :ID:       142a639c-e06d-4d4b-ad1c-edcd0d9ba6ce
       :Effort:   0:20
       :STYLE:    habit
       :END:

       - State "DONE"       from "NEXT"       [2020-07-05 Sun 10:15]
       - State "DONE"       from "NEXT"       [2020-07-04 Sat 10:30]
       - State "DONE"       from "NEXT"       [2020-07-03 Fri 10:05]
       - State "DONE"       from "NEXT"       [2020-07-02 Thu 11:15]

I forgot to mark it as done yesterday, which means that I would have
to manually edit /three/ timestamps to log the correct data: 1) the
SCHEDULED timestamp, 2) the :LAST_REPEAT: property, and 3) the state
change history.

If this is not currently possible, would it make sense to write a
wrapper around `org-todo', e.g. `org-todo-timewarp' or
`org-retroactive-todo', which interactively prompts for a timestamp
before invoking `org-todo'?

Another possibility would be to add yet another magic prefix argument
to `org-todo', but it seems that is already heavily overloaded, so it
would have to be 'C-u C-u C-u C-u' which isn't particularly
convenient.

I can even imagine users occasionally wanting to mark stuff done in
the future, e.g. if they have an activity planned for tomorrow while
they're offline.  So maybe using the word 'retroactive' in the wrapper
function name is a bit too limiting.

Cheers,
Adam