class RuboCop::Cop::ConditionCorrector

def correct_negative_condition(node)
  condition = negated_condition(node)
  lambda do |corrector|
    corrector.replace(node.loc.keyword, node.inverse_keyword)
    corrector.replace(condition.source_range,
                      condition.children.first.source)
  end
end

def negated_condition(node)
  condition = node.condition
  condition = condition.children.first while condition.begin_type?
  condition
end