signTypedData presents uint as hexadecimal in MetaMask UI

Hi @ricmoo thank you for the EIP712 integration,

I’m currently looking to move my projects to Signer.signTypedData, everything I need works as expected, except I’m facing a presentational issue when signing data containing uint type with MetaMask.

• uint,…,uint256 are presented to MetaMask’s users in hexadecimal format.
• uint are displayed human readable when calling Web3Provider.send('eth_signTypedData_v4', args).

The issue seems to be only presentational as the resulting signature is the same in both cases.

Here is a demo of the issue: https://codesandbox.io/s/gracious-raman-id9cg?file=/src/index.js

[PierreJeanjacquot]

Looks great, thank you @ricmoo! 🎉

[ricmoo]

The JSON-RPC definition of signTypedData is a bit loose in explaining what the payload should look like for values. Currently, I convert everything to a value compatible with results (e.g. quantity for numbers, which is a hex string without any leading zeros). I can make the payload generator return decimal numbers easy enough, but that should be something I would expect the client (i.e. MetaMask) to handle for display logic.

I’ll ping them for their opinions and maybe they have better docs as to input value formats. 😃