hardhat/src/internal/builtin-plugins/hhu/tasks/hash/keccak.ts

Hardhat is an extensible developer tool that helps smart contract developers increase productivity by reliably bringing together the tools they want.

import type { NewUtilsTaskActionFunction } from "../../types.js";

import { HardhatError } from "@nomicfoundation/hardhat-errors";
import { utf8StringToBytes } from "@nomicfoundation/hardhat-utils/bytes";
import { keccak256 } from "@nomicfoundation/hardhat-utils/crypto";
import {
  bytesToHexString,
  getUnprefixedHexString,
  hexStringToBytes,
  isHexString,
  isPrefixedHexString,
} from "@nomicfoundation/hardhat-utils/hex";

interface KeccakActionArguments {
  value: string;
}

const keccakAction: NewUtilsTaskActionFunction<KeccakActionArguments> = async ({
  value,
}) => {
  let bytes: Uint8Array;

  if (isPrefixedHexString(value)) {
    if (!isHexString(value)) {
      throw new HardhatError(
        HardhatError.ERRORS.CORE.GENERAL.INVALID_HEX_STRING,
        { value },
      );
    }

    if (getUnprefixedHexString(value).length % 2 !== 0) {
      throw new HardhatError(HardhatError.ERRORS.CORE.ARGUMENTS.INVALID_VALUE, {
        value,
        name: "value",
        reason: "it must have an even number of hex digits",
      });
    }

    bytes = hexStringToBytes(value);
  } else {
    bytes = utf8StringToBytes(value);
  }

  console.log(bytesToHexString(await keccak256(bytes)));
};

export default keccakAction;