How many Ubuntu branches share history with upstream?

[James Westby]

On Wed, 10 Feb 2010 15:16:18 +0100, Jelmer Vernooij <jelmer at canonical.com> wrote:
> So checking whether a revision is part of another branches' ancestry is
> not really possible then, if I understand the current database scheme
> correctly. You should be able to detect the common ancestry in most of
> the cases by just checking that the first revision of the upstream
> branch and first revision of the packaging branch have the same revid.
> 
> This won't allow you to detect the situation where the packaging branch
> was created first and the upstream merged into it later, but as far as I
> can tell that's quite rare.

Quite rare due to file id differences.

I'd like to start encouraging developers to merge upstream in as a
second root, but I don't want to do that until we can handle the file-id
differences smoothly.

So yes, I'd agree that would be a reasonable approximation currently,
but it's not sure to hold over time.

Thanks,

James