Identifiers with `$` are not recognized

[ardislu]

Describe the bug

Minimum code to reproduce the issue:

import { parseAbi } from 'abitype';

const abi = [
  'function _()',
  'function $()',
  'function $_()',
  'function $_a9()',
  'function a9$_()'
];

const result = parseAbi(abi);

Expected result: ABI is parsed successfully.

Actual result: UnknownSignatureError is thrown:

node_modules\abitype\src\human-readable\runtime\utils.ts:148
  throw new UnknownSignatureError({ signature })
        ^
UnknownSignatureError: Unknown signature.

---

I believe the issue is with the regex to match the function name (functionSignatureRegex in /src/human-readable/runtime/signatures.ts):

const functionSignatureRegex =
  /^function (?<name>[a-zA-Z0-9_]+)\((?<parameters>.*?)\)(?: (?<scope>external|public{1}))?(?: (?<stateMutability>pure|view|nonpayable|payable{1}))?(?: returns\s?\((?<returns>.*?)\))?$/

From the Solidity docs, the regex to match a valid identifier is: [a-zA-Z$_][a-zA-Z0-9$_]*. So it should be a quick fix:

-  /^function (?<name>[a-zA-Z0-9_]+)\((?<parameters>.*?)\)(?: (?<scope>external|public{1}))?(?: (?<stateMutability>pure|view|nonpayable|payable{1}))?(?: returns\s?\((?<returns>.*?)\))?$/
+  /^function (?<name>[a-zA-Z$_][a-zA-Z0-9$_]*)\((?<parameters>.*?)\)(?: (?<scope>external|public{1}))?(?: (?<stateMutability>pure|view|nonpayable|payable{1}))?(?: returns\s?\((?<returns>.*?)\))?$/

I only tested functions, but events, errors, structs, etc. all use the same identifier logic so those regexes should be updated too.

Also wanted to note this ABI works in ethers as expected:

const abi = [
  'function _()',
  'function $()',
  'function $_()',
  'function $_a9()',
  'function a9$_()'
];
const ethers = await import('https://cdn.jsdelivr.net/npm/ethers@6.6.2/+esm');
const interface = new ethers.Interface(abi);
interface.getFunction('$').selector;
// '0xf461e06a'

Lastly for reference, I was able to successfully deploy a smart contract on Sepolia using these identifiers and uploaded it to Etherscan: https://sepolia.etherscan.io/address/0x8ae917bd7ba1bc35ebf7ef1e6ff815565647ab9a#code

Link to Minimal Reproducible Example

No response

Steps To Reproduce

No response

Package Version

0.9.0

TypeScript Version

5.1.6

Anything else?

No response

Validations

• Checked there isn't already an issue that exists for the bug you encountered.
• Followed the Code of Conduct.
• Read the Contributing Guide.

[Raiden1411]

You are right. Feel free to create a PR to fix this. This does affect also error and event signatures. This should also affect the regex for named parameters

[github-actions]

This issue has been locked since it has been closed for more than 14 days.

If you found a concrete bug or regression related to it, please open a new bug report with a reproduction against the latest ABIType version. If you have any other comments you can create a new discussion.