They could be tested if languages supported doctests like Elixir: https://elixir-lang.org/getting-started/mix-otp/docs-tests-and-with.html#doctests https://elix

They could be tested if languages supported doctests like Elixir: https://elixir-lang.org/getting-started/mix-otp/docs-tests-and-with.html#doctests https://elixir-lang.org/getting-started/mix-otp/docs-tests-a... however, increasingly my view is: the less you test methods and components in isolation, the better. Unit tests are highly overrated and used too much to the detriment of all other testing.