Launchpad plugin install is optional - but required for bzr-explorer to run

[Ken Halprin]

The launchpad integration plugin appears to be required for bzrw to run.

On a machine without Bazaar installed.
1) Run setup (via windows installer)
2) De-select the launchpad integration plugin
3) After setup completes, run bzrw. The process starts and immediately exits. The following is in .bzr.log:

Wed 2010-11-03 12:15:36 -0500
0.453 bazaar version: 2.2.1
0.453 bzr arguments: [u'explorer']
0.453 looking for plugins in C:/Users/khalprin/AppData/Roaming/bazaar/2.0/plugins
0.453 looking for plugins in C:/Program Files (x86)/Bazaar/plugins
2.200 encoding stdout as osutils.get_user_encoding() 'cp1252'
2.855 Traceback (most recent call last):
  File "bzrlib\commands.pyo", line 912, in exception_to_return_code
  File "bzrlib\commands.pyo", line 1112, in run_bzr
  File "bzrlib\commands.pyo", line 690, in run_argv_aliases
  File "bzrlib\commands.pyo", line 705, in run
  File "bzrlib\cleanup.pyo", line 135, in run_simple
  File "bzrlib\cleanup.pyo", line 165, in _do_with_cleanups
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\commands.py", line 161, in run
  File "bzrlib\lazy_import.pyo", line 106, in __getattribute__
  File "bzrlib\lazy_import.pyo", line 89, in _replace
  File "bzrlib\lazy_import.pyo", line 192, in _import
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\explorer.py", line 31, in <module>
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\hosted_url_resolver.py", line 20, in <module>
ImportError: No module named launchpad

2.855 return code 3

[Gary van der Merwe (garyvdm)]

I think the best way to fix this, is to make BE fail gracefully when the launchpad integration plugin is not installed.

[Alexander Belchenko (bialix)]

Workaround: install launchpad plugin.