When trying to interact with a newer format, tell the user about upgrading instead of erroring

[Martin Albisetti]

There are many cases where you can try to interact with a newer, supported format. In those cases, we error out with something like:

bzr: ERROR: KnitPackRepository('file:///home/projects/.bzr/repository/')
is not compatible with
KnitPackRepository('file:///home/development/trunk/.bzr/repository/')
different rich-root support

Not very helpful.
Instead of that error, we should tell the user something like:
"The branch you're trying to access is using a newer bzr format. To work with it, you should upgrade your repository by using 'bzr upgrade'."

[Jared Hance (mathepic)]

How would it know that its a newer format?

It wouldn't have information on that format. It could either be a normal format or just a corrupted repository.

[Robert Collins (lifeless)]

On Fri, 2009-10-09 at 23:58 +0000, Jared Hance wrote:
> How would it know that its a newer format?
>
> It wouldn't have information on that format. It could either be a normal
> format or just a corrupted repository.

The example Martin gave indicates thats bzr knows both formats. We have
a different error on unknown formats - we show the format string, which
includes a human readable hint.

-Rob

[David Wagner (daw-bugzilla)]

Did this ever get addressed? I just ran into this situation today, and found it quite confusing to get this error message out of the blue. I agree with the original poster that his suggested error message would have been a lot more helpful. The existing error message is inscrutable (it might as well have said "error: the wizzgriff arglebarfed the gizmadget, sucks to be you") and also failed to provide me with any information about what I should do to correct the situation.

[Martin Pool (mbp)]

This is not fixed yet.