[Duplicity-talk] 0.5.12 TypeError (with unnecessary signature chain?)

[Dylan Alex Simon]

I'm getting this error when doing collection-status and other operations on a
backup that works with 0.5.06 and 0.4.11 (haven't tried other intermediate
versions):

Traceback (most recent call last):
  File "/usr/bin/duplicity", line 743, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 736, in with_tempdir
    fn()
  File "/usr/bin/duplicity", line 655, in main
    globals.archive_dir).set_values()
  File 
"/usr/local/duplicity-0.5.12/lib/python2.6/site-packages/duplicity/collections.py",
 line 557, in set_values
    self.warn(sig_chain_warning)
  File 
"/usr/local/duplicity-0.5.12/lib/python2.6/site-packages/duplicity/collections.py",
 line 626, in warn
    + "\n" + "\n".join(self.other_sig_names),
TypeError: bad operand type for unary +: 'str'

I didn't see any similar reports.  I can provide the full -v9 messages if
they'll be useful, but this seems to be related to the "unnecessary signature
chains" messages I've been getting since a long-ago upgrade.  There are two
backups, which older versions find (though really both should have
signatures):
> Warning, found unnecessary signature chain(s)
> Found 1 backup chains without signatures.
> Found a complete backup chain with matching signature chain:

:-Dylan