[rfc] [patch] speeding up bzr log with a tree delta iterator

[Denys Duchier]

Aaron Bentley <aaron.bentley at utoronto.ca> writes:

> Denys Duchier wrote:
>> I don't think that's meaningful.  You need a revision history to do a delta,
>> otherwise you can't know which is the "previous" revision (you can use left-most
>> parent, but that's arbitrary).
>
> It's not arbitrary.  It represents the changes that this revision made
> to the tree in which it was committed.

I know this. I meant that bzr log would behave in a way that's quite different
from what it usually means.  Normally it is about the history of your branch.
In this case it is about 1 delta in another branch.  You can't even do a delta
iteration in that other branch because... well you don't have that other branch
(there's no branch identity anyway).  So yes, it does feel a little arbitrary to
me.

However, if you insist to have it, I'd much prefer to special case that case in
my iterator rather than to pass a padded list of revisions because, in order to
create the latter, the caller needs to perform more work.

Cheers,

--Denys