an ICE happening when we call a closure result from if/else

[alehander92]

Aim

To fix this and make it run without an error: an example by @jfecher in #1959 (comment)

fn main() {
    let x: u32 = 32;

    let f = if x > 2 {
        || x
    } else {
        || x + 2342
    };

    dep::std::println(f());
}

Expected Behavior

pass without errors

Bug

this lead to an ICE related to tuples and SSA:
If nodes have a fn type when a closure is returned, while monomorphization rewrites mean, the actual type should be a Tuple: happening when we call a closure preserved in a variable, resulting from such an if.

To Reproduce

No response

Installation Method

Compiled from source

Nargo Version

No response

Additional Context

No response

Would you like to submit a PR for this Issue?

Yes

Support Needs

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