() is encoded as a SC_SPEC_TYPE_TUPLE instead of SC_SPEC_TYPE_VOID

[wildework]

What version are you using?

soroban-sdk: 20.2.0

What did you do?

#![no_std]
use soroban_sdk::{contract, contractimpl, Env};

#[contract]
pub struct Contract;

#[contractimpl]
impl Contract {
    pub fn void_fn(env: Env, void_argument: ()) -> () {
        void_argument
    }
}

What did you expect to see?

I expected to see void_fn specification in the compiled .wasm to have the argument void_argument typed as SC_SPEC_TYPE_VOID and the return value typed as SC_SPEC_TYPE_VOID.

What did you see instead?

Both were typed as SC_SPEC_TYPE_TUPLE.