is there a rule, that would check for unnecessary functions in final classes? For example `isInputVa...

# detekt

[Peter]

is there a rule, that would check for unnecessary functions in final classes? For example isInputValid() :

data class EmailSignUpState(
    val emailValid: Boolean = false,
    val passwordValid: Boolean = false,
) {
    fun isInputValid(): Boolean {
        return emailValid && passwordValid
    }
}

[Brais Gabin]

There is a rule that forbids functions on data classrs

[marschwar]

Why do you consider this function unnecessary?

[Peter]

hm, I think there are some use cases for functions, sometimes

[Peter]

because all fields are final?

val isInputValid = emailValid && passwordValid

[Peter]

I felt like that makes sense 🤔

[marschwar]

That is true but to me this feels very nitpicky to prohibit this. How big is the performance impact really?

[Peter]

probably no performance gain. Maybe more like a code style choice. More compact and less brackets, dunno 🙂

[Brais Gabin]

But even if they are not final you can do the same using val ... get(). Any function without parameters can be replaced with a property

[Brais Gabin]

But, anyways I feel that something like that would be a very controversial role so a third party rule seems the place for it.

[Peter]

I guess it could still be a rule that is disabled by default, if my use case seems valid to you

[Brais Gabin]

To me it is not valid. I mean, I don't see any problem with that function. Probably I would write it as an extension function or extension property.