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eip712HashTypedData

Signature

function eip712HashTypedData(
  string calldata jsonData
) external pure returns (bytes32);

Description

Returns the complete EIP-712 digest: keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash)).

jsonData must be a self-describing EIP-712 JSON payload containing domain, types, primaryType, and message fields. This cheatcode is fully self-contained and does not require any eip712Types configuration in your hardhat.config.ts.

Example

string memory json = '{'
    '"domain":{"name":"Ether Mail","version":"1","chainId":1,"verifyingContract":"0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC"},'
    '"types":{'
        '"EIP712Domain":[{"name":"name","type":"string"},{"name":"version","type":"string"},{"name":"chainId","type":"uint256"},{"name":"verifyingContract","type":"address"}],'
        '"Mail":[{"name":"from","type":"Person"},{"name":"to","type":"Person"},{"name":"contents","type":"string"}],'
        '"Person":[{"name":"wallet","type":"address"},{"name":"name","type":"string"}]'
    '},'
    '"primaryType":"Mail",'
    '"message":{"from":{"wallet":"0xA","name":"Alice"},"to":{"wallet":"0xB","name":"Bob"},"contents":"hello"}'
'}';

bytes32 digest = cheats.eip712HashTypedData(json);

SEE ALSO