Execute (func() -> undefined):
  let completed_item = {'info': 'func() -> undefined'}
  let result = cm_parser#erlang#parameters(completed_item)
  AssertEqual ['()'], result

Execute (func(foo) -> ran()):
  let completed_item = {'info': 'func(foo) -> ran()'}
  let result = cm_parser#erlang#parameters(completed_item)
  AssertEqual ['(foo)'], result

Execute (func(foo, bar) -> undefined | ran()):
  let completed_item = {'info': 'func(foo, bar) -> undefined | ran()'}
  let result = cm_parser#erlang#parameters(completed_item)
  AssertEqual ['(foo, bar)'], result