bzr upgrade should accept a --stacked-on parameter

[Vincent Ladeuil]

I wanted to push some changes on lp:~bzr-core/bzr/devnotes and discovered it was still using the 1.9 format.

No problem thought I, let's just upgrade it !

Ha ha.

The upgrade failed successfully: a new '.bzr' was created in 2a format but still stacked on /~bzr/bzr/trunk our old beloved trunk

The solution was to create a branch.conf containing:

parent_location = lp-hosted:///~bzr-core/bzr/devnote
stacked_on_location = /~bzr-pqm/bzr/bzr.dev/

and upload it with lftp.

As jelmer said on IRC: "This is too hard for somebody not familiar with the internals though :-/"

Adding a --stacked-on parameter to upgrade should address this case.

Some sanity check should be performed to ensure the new stacked-on repo contains the necessary (hand-waving) revisions.

If the upgrade branch contains ghosts though, this may be tricky (or require more thought than I want to put in this report).

Also, upgrade without this parameter shouldn't succeed at all as the branch was left in a broken state.

[Vincent Ladeuil (vila)]

For the record:

lftp sftp://bazaar.launchpad.net/~bzr-core/bzr/devnotes/
cd ok, cwd=~bzr-core/bzr/devnotes
lftp bazaar.launchpad.net:~bzr-core/bzr/devnotes> ls
drwxr-xr-x 5 1001 1005 4096 Nov 29 15:34 .bzr
drwxr-xr-x 5 1001 1005 4096 Nov 29 15:34 backup.bzr.~1~
drwxr-xr-x 5 1001 1005 4096 Nov 29 15:18 backup.bzr.~2~

~1~ should still contain the branch and repo before upgrade
~2~ is a first attempt and contain a 2a branch and repo