web3.js 1.0.0-beta.41 batch.execute() : Error: Given input "function (err, res) {....}" is not a number.

[kim-keepcoding]

const contract = new web3.eth.Contract(abi, address);

const batch = new web3.BatchRequest();
function callback(err,res){
    console.log(err,res)
}
batch.add(contract.methods.balance(address).call.request({from: '0x0000000000000000000000000000000000000000'}, callback));
batch.execute();

work fine with
web3.eth.getBalance.request( "0x0000000000000000000000000000000000000000", "latest", callback )

Expected behavior

execute batch and log callback properly

Actual behavior

throw Error

Steps to reproduce the behavior

1. [First step]
2. [Second step]
3. [and so on...]

Error Logs

Error: Given input "function callback(err,res){
    console.log(err,res)
}" is not a number.
    at Object.numberToHex (node_modules/web3-utils/dist/web3-utils.cjs.js:114:11)
    at inputBlockNumberFormatter (node_modules/web3-core-helpers/dist/web3-core-helpers.cjs.js:37:16)
    at Object.inputDefaultBlockNumberFormatter (node_modules/web3-core-helpers/dist/web3-core-helpers.cjs.js:25:10)
    at CallContractMethod.beforeExecution (node_modules/web3-core-method/dist/web3-core-method.cjs.js:1217:44)

Versions

[NPM@6.4.1, Node@v8.12.0, Web3.js@1.0.0-beta.41, OS:macOs@10.14.2]

[nivida]

Thanks for creating this issue!

I will check this and probably directly fix it tomorrow.