inline_test

module MathFunctions
  include InlineTest

  def factorial(n)
    (1..n).inject(1) { |acc, x| acc * x}
  end

  unit_test do
    assert factorial(6) == 720
    assert factorial(5) == 120
  end
end

module InlineTest
  def env_is_testy?
    true
  end
  if env_is_testy?
    def unit_test(name, &block)
      block[]
    end
  else
    def unit_test(*args, &block)
    end
  end
end