Error: eddsa.verifyMiMCSponge

[johnson86tw]

When I run this script:

console.log(eddsa.verifyMiMCSponge(msgHash, signature, pubKey));

First problem would happen in 'bigInt' with 'ReferenceError: bigInt is not defined'

code:

let Pright = babyJub.mulPointEscalar(A, hm.times(bigInt("8")));

After I change bigInt to BigInt, it would run error below:

/Users/howard/Desktop/circom-playground/node_modules/circomlib/src/eddsa.js:207
    let Pright = babyJub.mulPointEscalar(A, hm.times(BigInt("8")));
                                               ^

TypeError: hm.times is not a function
    at Object.verifyMiMCSponge (/Users/howard/Desktop/circom-playground/node_modules/circomlib/src/eddsa.js:207:48)
    at Object.<anonymous> (/Users/howard/Desktop/circom-playground/eddsa/js/index.js:28:19)

sorry, I can't really understand how these cryptography works under the hood.