Comment 1 for bug 307277

I agree, it would be nice to give a clearer error in this case.

A possible alternative would be to write a short README file to the 'upload' directory (and to the 'obsolete' directory too), with contents along the lines of "This is part of a Bazaar repository. Do not remove this directory." That would be enough to fool simple automated tools, as well as discouraging simple humans from making the same mistake by hand :)