Invalid serialization of type aliased values unless argument name matches type alias name

[halfbakedsneed]

Strange one. Take this simple program, and accompanying invocation:

// 0.29.0

use anchor_lang::prelude::*;

pub type MyType = [u8; 3];

#[program]
pub mod test {
    use super::*;

    pub fn initialize(ctx: Context<Initialize>, kek: MyType) -> Result<()> {
        msg!("{:?}", kek);

        Ok(())
    }
}

#[derive(Accounts)]
pub struct Initialize {}

await program.methods.initialize([1, 2, 3]).rpc();

Expected Behaviour

I should see [1, 2, 3] in the program logs.

Current Behaviour

I see [0, 0, 0] in the program logs.

If I rename the argument kek to my_type, then everything works as expected! (hence why the example in the release notes works).

Possible Fix

I believe the culprit lies within the client code parsing the IDL into a layout here.

Unless I'm misunderstanding something, I believe this case should actually be written as follows, no?

case "alias": {
  return IdlCoder.fieldLayout(
-   { type: typeDef.type.value, name: typeDef.name },
+   { type: typeDef.type.value, name },
    types
  );
}

This patch resolves the quirk, but I'm not sure of what other effects it may have.

[acheroncrypto]

Yes, that's definitely a bug and your fix is correct — it should use name variable similar to the other defined types in typeDefLayout method.

I'm currently working on a rather large PR with regards to the IDL and it doesn't have this problem. However, if you'd like to make a PR with this fix, we can merge it.