viem analogue of ethers.utils.solidityKeccak256?

[kostysh]

How to implement the same behaviour as in the solidityKeccak256 utility of ethers.js?

I am trying to do it this way:

import { toHex, concat, keccak256 } from 'viem';

const opt = {
 id: '0x88cadab56ea4e0eb38531d2313ed7f390aa9faf0661dcf98daa980342f1dcc97',
 price: 1n,
 asset: '0x12DC8e8De1C576284ab25842C2750c749c326301',
};

keccak256(
  concat([opt.id, toHex(opt.price), opt.asset]),
);

but the ethers implementation results in different hash (((

utils.solidityKeccak256(
  ["bytes32", "uint256", "address"],
  [opt.id, opt.price, opt.asset]
)

So, how to implement solidity flavoured keccak256 in the right way in viem?

I have created an example on codesandbox: https://codesandbox.io/s/vibrant-benz-r5ncp2?file=/src/index.ts

[jxom]

You’ll need to use encodePacked instead of concat.

[tk-o]

Here's an example of code that worked for me:

const [types, data] = [
  ['address', 'uint256', 'uint8', 'uint256', 'uint256'],
  [
    senderAddress,
    stakedAmount,
    nodeType,
    blockNumber,
    nonce,
  ],
];

const dataHash = keccak256(encodePacked(types, data), 'bytes');

const signature = walletClient.signMessage({
  message: {
    raw: dataHash,
  },
});

The following smart contract verification logic works well with the client signature from above:

bytes32 messageHash = keccak256(
    abi.encodePacked(msg.sender, _stakedAmount, _nodeType, _block, currentNonce)
);

require(_verify(messageHash, _signature, adminSigner), "Invalid signature");

// verify function body

function _verify(
    bytes32 data,
    bytes memory signature,
    address account
) internal pure returns (bool) {
    return data.toEthSignedMessageHash().recover(signature) == account;
}