feat: implements chainName

[0xItadaki]

Closes EFI-429, EFI-438

[linear]

EFI-429 chainName

• function chainName(bytes calldata _chainIdBytes) external view returns (string memory)
  • Retrieves the primary human-readable ENS name string associated with a given EIP-7930 chain identifier (bytes, with AddressLength = 0).
  • Assumes the input chainIdBytes is a correctly formatted EIP-7930 sequence.
  • Off-chain tooling used to set reverse records should ensure canonical name formatting (e.g., lowercase, UTS#46 normalization) of the ENS name string.
  • Implementation:
    1. Hash the input: bytes32 identifierHash = keccak256(chainIdBytes);
    2. Convert hash to hex string (conceptual step, e.g., using an internal _bytes32ToHexString helper). Let this be hexIdentifierHash.
    3. Construct key: string memory key = string.concat(CHAIN_IDENTIFIER_EIP7930_KEY, hexIdentifierHash);
    4. Retrieves data: bytes memory data = this.getRecord(REVERSE_LOOKUP_NODE, key);
    5. Handles not found: if (data.length == 0) { return ""; }
    6. Decodes and returns: return abi.decode(data, (string)); (This will revert if data is not a valid ABI-encoded string).

[linear]

EFI-438 chainName

[0xAustrian]

_chainName = _data.length == 0 ? '' : abi.decode(_data, (string));, wdyt?

[0xItadaki]

Is there a performance reason for doing that? I think two lines makes it easier to follow, but I don't have a strong preference

[0xAustrian]

I'm not sure if there is a gas improvement, just personal opinion, feel free to keep it as is.

[0xItadaki]

I'll keep it. I think it makes the different branches more obvious