test_build[zip]

Traceback (most recent call last):
  File "/home/phillipsmyth/projects/buildstream/tests/testutils/runcli.py", line 263, in invoke
    cli.main(args=args or (), prog_name=cli.name, **extra)
  File "/home/phillipsmyth/projects/buildstream/buildstream/_frontend/main.py", line 135, in override_main
    standalone_mode=standalone_mode, **extra)
  File "/home/phillipsmyth/.local/lib/python3.5/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/phillipsmyth/.local/lib/python3.5/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/phillipsmyth/.local/lib/python3.5/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/phillipsmyth/.local/lib/python3.5/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/phillipsmyth/.local/lib/python3.5/site-packages/click/decorators.py", line 27, in new_func
    return f(get_current_context().obj, *args, **kwargs)
  File "/home/phillipsmyth/projects/buildstream/buildstream/_frontend/main.py", line 456, in show
    app.initialize(elements, except_=except_, use_configured_remote_caches=downloadable)
  File "/home/phillipsmyth/projects/buildstream/buildstream/_frontend/main.py", line 876, in initialize
    track_elements=track_elements)
  File "/home/phillipsmyth/projects/buildstream/buildstream/_pipeline.py", line 154, in initialize
    self.initialize_workspaces()
  File "/home/phillipsmyth/projects/buildstream/buildstream/_pipeline.py", line 182, in initialize_workspaces
    for element_name, source, workspace in self.project._list_workspaces():
  File "/home/phillipsmyth/projects/buildstream/buildstream/_project.py", line 293, in _list_workspaces
    for source, _ in _yaml.node_items(self._workspaces[element]):
  File "/home/phillipsmyth/projects/buildstream/buildstream/_yaml.py", line 408, in node_items
    for key, value in node.items():
  File "/home/phillipsmyth/.local/lib/python3.5/site-packages/ruamel/yaml/comments.py", line 575, in __iter__
    for key in self._mapping._keys():
  File "/home/phillipsmyth/.local/lib/python3.5/site-packages/ruamel/yaml/comments.py", line 786, in _keys
    for x in ordereddict.__iter__(self):
RuntimeError: OrderedDict mutated during iteration