class ParallelTests::Gherkin::Runner

def tests_in_groups(tests, num_groups, options = {})
  @test_file_name = "scenario" if options[:group_by] == :scenarios
  method = "by_#{options[:group_by]}"
  if Grouper.respond_to?(method)
    Grouper.send(method, find_tests(tests, options), num_groups, options)
  else
    super
  end
end