loom needs to hook into 'bzr nick' to make that rename the thread -or- refuse to change.

[Sebastian Kuzminsky]

0 seb@water /home/seb/emc2/module-interface> bzr show-loom
  module-interface
=>upstream
0 seb@water /home/seb/emc2/module-interface> bzr up-thread
All changes applied successfully.
Moved to thread 'module-interface'.
0 seb@water /home/seb/emc2/module-interface> bzr nick
module-interface
0 seb@water /home/seb/emc2/module-interface> bzr nick minor-fixes
bzr: ERROR: exceptions.KeyError: u'minor-fixes'

Traceback (most recent call last):
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 846, in run_bzr_catch_errors
    return run_bzr(argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 797, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 499, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.5/site-packages/bzrlib/builtins.py", line 2536, in run
    branch.nick = nickname
  File "/usr/lib/python2.5/site-packages/bzrlib/branch.py", line 139, in _set_nick
    self.get_config().set_user_option('nickname', nick, warn_masked=True)
  File "/usr/lib/python2.5/site-packages/bzrlib/config.py", line 675, in set_user_option
    self._get_branch_data_config().set_option(value, name)
  File "/usr/lib/python2.5/site-packages/bzrlib/config.py", line 921, in set_option
    self.branch.unlock()
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/loom/branch.py", line 687, in unlock
    if dict(state.get_threads_dict())[self.nick][0] != lastrev:
KeyError: u'minor-fixes'

bzr 1.5 on python 2.5.2 (linux2)
arguments: ['/usr/bin/bzr', 'nick', 'minor-fixes']
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'en_US.UTF-8'
plugins:
  bzrtools /usr/lib/python2.5/site-packages/bzrlib/plugins/bzrtools [1.5.0]
  dbus /usr/lib/python2.5/site-packages/bzrlib/plugins/dbus [unknown]
  gtk /usr/lib/python2.5/site-packages/bzrlib/plugins/gtk [0.94.0]
  launchpad /usr/lib/python2.5/site-packages/bzrlib/plugins/launchpad [unknown]
  loom /usr/lib/python2.5/site-packages/bzrlib/plugins/loom [1.4.0dev0]
  qbzr /usr/lib/python2.5/site-packages/bzrlib/plugins/qbzr [0.9.2]
  rebase /usr/lib/python2.5/site-packages/bzrlib/plugins/rebase [0.3.0]
  svn /usr/lib/python2.5/site-packages/bzrlib/plugins/svn [0.4.10]
*** Bazaar has encountered an internal error.
    Please report a bug at https://bugs.launchpad.net/bzr/+filebug
    including this traceback, and a description of what you
    were doing when the error occurred.

[Sebastian Kuzminsky (seb-highlab)]

After the above command resulted in an internal error, the nick was changed, and the branch was left locked with no thread selected:

4 seb@water /home/seb/emc2/module-interface> bzr nick
minor-fixes
0 seb@water /home/seb/emc2/module-interface> bzr show-loom
  module-interface
  upstream
0 seb@water /home/seb/emc2/module-interface> bzr up-thread
Unable to obtain lock file:///home/seb/emc2/module-interface/.bzr/repository/lock
held by <email address hidden> on host water [process #17677]
locked 5 minutes, 9 seconds ago
Will continue to try until 14:50:13

^Cbzr: interrupted

I broke the lock, but the branch seems sort of horked now:

3 seb@water /home/seb/emc2/module-interface> bzr break-lock
Break lock file:///home/seb/emc2/module-interface/.bzr/branch/lock
held by <email address hidden> on host water [process #17677]
locked 5 minutes, 19 seconds ago? [y/n]: y
Break lock file:///home/seb/emc2/module-interface/.bzr/repository/lock
held by <email address hidden> on host water [process #17677]
locked 5 minutes, 21 seconds ago? [y/n]: y
0 seb@water /home/seb/emc2/module-interface> bzr nick
minor-fixes
0 seb@water /home/seb/emc2/module-interface> bzr show-loom
  module-interface
  upstream
0 seb@water /home/seb/emc2/module-interface> bzr down-thread
bzr: ERROR: exceptions.KeyError: u'minor-fixes'

Traceback (most recent call last):
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 846, in run_bzr_catch_errors
    return run_bzr(argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 797, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 499, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/loom/commands.py", line 274, in run
    return tree.down_thread(thread)
  File "/usr/lib/python2.5/site-packages/bzrlib/decorators.py", line 167, in write_locked
    self.unlock()
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/loom/tree.py", line 231, in unlock
    self.tree.unlock()
  File "/usr/lib/python2.5/site-packages/bzrlib/workingtree_4.py", line 1146, in unlock
    self.branch.unlock()
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/loom/branch.py", line 687, in unlock
    if dict(state.get_threads_dict())[self.nick][0] != lastrev:
KeyError: u'minor-fixes'

bzr 1.5 on python 2.5.2 (linux2)
arguments: ['/usr/bin/bzr', 'down-thread']
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'en_US.UTF-8'
plugins:
  bzrtools /usr/lib/python2.5/site-packages/bzrlib/plugins/bzrtools [1.5.0]
  dbus /usr/lib/python2.5/site-packages/bzrlib/plugins/dbus [unknown]
  gtk /usr/lib/python2.5/site-packages/bzrlib/plugins/gtk [0.94.0]
  launchpad /usr/lib/python2.5/site-packages/bzrlib/plugins/launchpad [unknown]
  loom /usr/lib/python2.5/site-packages/bzrlib/plugins/loom [1.4.0dev0]
  qbzr /usr/lib/python2.5/site-packages/bzrlib/plugins/qbzr [0.9.2]
  rebase /usr/lib/python2.5/site-packages/bzrlib/plugins/rebase [0.3.0]
  svn /usr/lib/python2.5/site-packages/bzrlib/plugins/svn [0.4.10]
*** Bazaar has encountered an ...

[Robert Collins (lifeless)]

The nick command is not integrated into loom yet; just set the nick back
to the previous thread and then resume using loom.

note that changing threads in a loom will change your nick for you.

-Rob