Re: Switching to bzr: what remains to be done?

[Stefan Monnier <monnier@iro.umontreal.ca>]

> Actually the repository that is incremental is:
> http://bzr.notengoamigos.org/emacs/trunk/

Sorry, that was a typo, yes.

>> - includes renames.  Apparently none of the conversion tools provide
>> that since the info is only available in the Arch repository right
>> now, but that has commits that bundle up several CVS commit into one.

> I do have an import of the Arch repository, but I wouldn't recommend it
> as it throws away most of the CVS revision history.  I have no idea how
> you would go about trying to merge the Arch information into one of the
> other repositories.

I don't either.  Andreas somehow manages to extract the merge info from
the Arch archive and mix it up with the CVS data to generate&update its
Git repository.  Not sure if something similar can be done for the renames.

>> - is complete.  The http://bzr.notengoamigos.org/emacs-merges/trunk/
>> seems to have some missing elements (IIRC a few CVS tags were
>> missing).
> I think that this could easily be fixed.  Could you give an example from
> emacs-merges?

I meant the http://bzr.notengoamigos.org/emacs/trunk/ branch, sorry.
As far as I can tell the emacs-merges branch is complete.

>> Another issue that AFAIK nobody has worked on, is how are we going to
>> handle the Gnus<->Emacs synchronization in the future.  I expect this to
>> be doable somehow, maybe by still going through Arch, but of course it
>> would probably be preferable to do it directly within Bzr, and in any
>> case it will require for someone to figure it out.
> I don't know how this works so it is hard to comment :).

I think it works pretty much as follows (except in Arch).  To set things
up, the following was done once:

  - cd .../emacs
  - bzr pull
  - bzr merge bzr://.../gnus
  - tons of random bogus conflicts, resolve them somehow

at this point, the VCS (i.e. hopefully Bzr can do it, Arch clearly does)
has figure out that Gnus's "lisp/gnus.el" corresponds to Emacs's
"lisp/gnus/gnus.el" and things like that, so you can then subsequently
treat the two repositories as two branches of the same code, just where
one holds a lot more files than the other.  So you can do

  - bzr merge bzr://.../gnus

and changes will properly get merged into the right files.
Now of course, I don't know how the two-way sync can work, I'm not even
sure how Miles does it for Arch.

> Unfortunately updating from CVS and getting the merge info seem to be
> mutually exclusive.

Clearly Andreas manages to do it, so there should be a way to do that
for Bzr as well.


        Stefan