Handle type clash

[h4x3rotab]

https://polkadot.js.org/docs/api/start/types.extend#type-clashes

As mentioned in the above link from polkadotjs-api, there could be type clashes, and a well known example is Balances::Balance = u128 and Assets::Balance = u64. In the current impl, subxt only handles Balance = u128, and will use this definition to decode Assets::Balance, causing a failure to decode the Assets events.

A simple approach like it in polkadotjs: in the type registry, let's add the pallet name for specific type look up. Usually the type definition don't require change, but for the type clashes, we can register a full type name {pallet}::{type} in the registry.

For example, we call:

event_type_registry.register_type_size::<u64>("Assets::Balance");

And in events.rs, whenever it looks up a type, try {pallet}::{type} before {type}.

[h4x3rotab]

Sample fix: https://github.com/Phala-Network/phala-blockchain/pull/190/files

[en]

I'm faced with the same problem.
There might be a solution after this PR is merged.
paritytech/substrate#8615

[ascjones]

Yes indeed, I'm back next week from holiday to work again on that and that should solve most custom type problems

[ascjones]

Closed by #294