[byby]

>You've written 3 functions instead off one.

3 functions is better. Think about it. Do people write all their stuff in one big function? No. Better to compose higher level functions with smaller ones rather then write one big monolith like you did. The more modular something is the better.

Also IO_function is there for illustration purposes. Technically it's just wrapping print with a name so you can understand the intent. In reality you just use the regular print here without a wrapper, so in actuality only two functions are defined.

>The job of ChatGPT was to make cool_function unit testable. You haven't done it.

It did. By giving it a return value. Just like you did by giving it a new input value.

>You still have cool_function using side effect generating code hitting the actual IO system.

Yeah but one component of cool_function is pure and you can unit test that. Cool function itself can never be tested because it generates no output, you test the unit components of cool function. That's the point of unit tests.

>Genuinely the worst unit test I have ever seen written, on a poor form per line basis, absolute bananas. If you don't understand why [i for i in range(4)] is bad in a unit test and [0,1,2,3] is correct then I need you to walk away from the computer.

Let's just talk about it like adults. Just tell me what exactly about it makes you think it's bad?

Most likely it's some pedantic stylistic philosophy you have? I'm thinking you only want to test literals? Perhaps you prefer [0,1,2,3]? Am I right on the money?

Logic potentially has errors so you don't put logic in your test code. Makes sense, but who cares. For trivial shit it's fine. While in this case the logic in the test is identical to the function, typically 'logic_function' represents something significantly more complex and the list comprehension so I could care less if I'm not following the strictest form of testing. The comprehension is just something akin to an alias shortcut I prefer to use over writing out a massive literal. For the toy example the test is pointless because the logic is identical but typically it's fine to use range as an alias to represent a sequence of numbers.

Someone who strictly follows these stylistic rules without seeing intent or having the ability to bend the rules is just an inflexible pedantic programmer. It's not good to boast about it either by telling other people to walk away from a computer. That's just rude.