bzr credits doesn't work on wily

[Alan Pope 🍺🐧🐱 🦄]

Trying bzr-stats to get credits from a project, it dies.

alan@deep-thought:/tmp/bzr-stats$ bzr credits .
bzr: ERROR: bzrlib.errors.NoSuchRevision: CHKInventoryRepository('file:///tmp/bzr-stats/.bzr/repository/') has no revision null:

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 930, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 1121, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 673, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 697, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 136, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 166, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/stats/cmds.py", line 422, in run
    credits = find_credits(a_branch.repository, last_rev)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/stats/cmds.py", line 375, in find_credits
    revs = repository.get_revisions(ancestry)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 155, in read_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/vf_repository.py", line 1398, in get_revisions
    return self._get_revisions(revision_ids)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 155, in read_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/vf_repository.py", line 1406, in _get_revisions
    raise errors.NoSuchRevision(self, revid)
NoSuchRevision: CHKInventoryRepository('file:///tmp/bzr-stats/.bzr/repository/') has no revision null:

bzr 2.7.0dev1 on python 2.7.10 (Linux-3.19.0-22-generic-x86_64-with-
    Ubuntu-15.10-wily)
arguments: ['/usr/bin/bzr', 'credits', '.']
plugins: bash_completion[2.7.0dev1], builddeb[2.8.6], bzrtools[2.6.0],
    changelog_merge[2.7.0dev1], explorer[1.3.0], grep[2.7.0dev1],
    launchpad[2.7.0dev1], netrc_credential_store[2.7.0dev1],
    news_merge[2.7.0dev1], po_merge[2.7.0dev1], qbzr[0.23.1], stats[0.2.0dev],
    weave_fmt[2.7.0dev1]
encoding: 'utf-8', fsenc: 'UTF-8', lang: 'en_GB.UTF-8'

*** Bazaar has encountered an internal error. This probably indicates a
    bug in Bazaar. You can help us fix it by filing a bug report at
        https://bugs.launchpad.net/bzr/+filebug
    including this traceback and a description of the problem.
alan@deep-thought:/tmp/bzr-stats$

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: bzr-stats 0.1.0+bzr51-1
ProcVersionSignature: Ubuntu 3.19.0-22.22-generic 3.19.8-ckt1
Uname: Linux 3.19.0-22-generic x86_64
ApportVersion: 2.17.3-0ubuntu4
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Jul 6 15:58:20 2015
InstallationDate: Installed on 2014-06-16 (385 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
PackageArchitecture: all
SourcePackage: bzr-stats
UpgradeStatus: Upgraded to wily on 2015-05-09 (58 days ago)

[Hans Joachim Desserud (hjd)]

I get the same error message when attempting to run `bzr credits .` in bzr repo. I didn't have anything better at hand so I simply branched lp:ubuntu/bzr-stats when testing.

Looks like this might have been broken for while though. I also get the same error message with bzr-stats 0.1.0+bzr51-1 on Ubuntu 14.04. bzr-stats 0.1.0-4build1 on Ubuntu 12.04 outputs a list of contributors though.