class RuboCop::Cop::Style::MixinGrouping

def separate_mixins(node)
  _receiver, mixin, *args = *node
  args.reverse!
  first_mixin = String.new("#{mixin} #{args.first.source}")
  args[1..-1].inject(first_mixin) do |replacement, arg|
    replacement << "\n#{indent(node)}#{mixin} #{arg.source}"
  end
end