Missing test coverage for builtin Eq/Hash/Show impl of tuples

[hackwaly]

No description provided.

[definfo]

It seems that Eq tests already exist in tuple/tuple_test.mbt, while Compare/Hash tests are still missing.

[FlammeShadow]

According to the current implementation, it seems that the hash value of (1, 2, 3) and (1, (2, 3)) are the same, and so on. Is this a potential problem? Or it doesn't make sense?
I refered to the boost::hash_value and got different result on std::tuple (1, (2, 3)) and (1, 2, 3). I didn't test Swift because its tuple types don't conform to Hashable protocol.

[definfo]

According to the current implementation, it seems that the hash value of (1, 2, 3) and (1, (2, 3)) is the same, and so on. Is this a potential problem? Or it doesn't make sense? I refered to the boost::hash_value and got different result on std::tuple (1, (2, 3)) and (1, 2, 3). I didn't test Swift because its tuple types don't conform to Hashable protocol.

I tested the hash implementation for tuple in Rust and got some weird results.

use std::hash::{DefaultHasher, Hash, Hasher};

fn calculate_hash<T: Hash>(t: &T) -> u64 {
    let mut s = DefaultHasher::new();
    t.hash(&mut s);
    s.finish()
}

fn main() {
    let tuple1 = (1, 2, 3);
    let tuple2 = (1, (2, 3));
    let tuple3 = (1 as u32, 2, 3);
    let tuple4 = (1 as i64, 2, 3);
    println!(
        "{} {} {} {}",
        calculate_hash(&tuple1), // 646939227381880718 
        calculate_hash(&tuple2), // 646939227381880718
        calculate_hash(&tuple3), // 646939227381880718
        calculate_hash(&tuple4), // 4417724211370468105
    ); 
    assert_eq!(calculate_hash(&tuple1), calculate_hash(&tuple2));
    assert_eq!(calculate_hash(&tuple1), calculate_hash(&tuple3));
    assert_ne!(calculate_hash(&tuple1), calculate_hash(&tuple4));
}

Moonbit's current implementation is consistent with Rust, except that multiple builtin types have not implemented Hash trait yet (eg. Int64, Array[Int] #938 ).

test "hash" {
    let tuple1 = (1, 2, 3)
    let tuple2 = (1, (2, 3))
    let tuple3 = (1U, 2, 3)
    // let tuple4 = (1L, 2, 3)
    inspect!(tuple1.hash() == tuple1.hash(), content="true")
    inspect!(tuple1.hash() == tuple2.hash(), content="true")
    inspect!(tuple1.hash() == tuple3.hash(), content="true")
    // inspect!(tuple1.hash() == tuple4.hash(), content="false") // Type Int64 does not implement trait Hash
}

[FlammeShadow]

It seems that Eq tests alreay exist

Show tests seem to exist too. So I just added Compare/Hash tests.