Demo code for web3.js error message

set_up_cpp_eth.js

var Web3 = require('web3');
var net = require('net');
//var web3 = new Web3('http://localhost:8545');
var web3 = new Web3(new Web3.providers.IpcProvider('/tmp/testeth/geth.ipc', net));

var params = {
    sealEngine: 'NoProof',
    options: {},
    params: {
        accountStartNonce: '0x',
        maximumExtraDataSize: '0x1000000',
        blockReward: '0x',
        allowFutureBlocks: '1',
		homsteadForkBlock: '0x',
		EIP150ForkBlock: '0x',
		EIP158ForkBlock: '0x'
    },
    genesis: {
      author: '0000000000000010000000000000000000000000',
      timestamp: '0x00',
      parentHash: '0x0000000000000000000000000000000000000000000000000000000000000000',
      extraData: '0x',
      gasLimit: '0x1000000000000'
    },
    accounts: {
      '0000000000000000000000000000000000000001': { 'wei': '1', 'precompiled': { 'name': 'ecrecover', 'linear': { 'base': 3000, 'word': 0 } } },
      '0000000000000000000000000000000000000002': { 'wei': '1', 'precompiled': { 'name': 'sha256', 'linear': { 'base': 60, 'word': 12 } } },
      '0000000000000000000000000000000000000003': { 'wei': '1', 'precompiled': { 'name': 'ripemd160', 'linear': { 'base': 600, 'word': 120 } } },
      '0000000000000000000000000000000000000004': { 'wei': '1', 'precompiled': { 'name': 'identity', 'linear': { 'base': 15, 'word': 3 } } },
    }
};

web3.extend(
    {
        property: 'test',
        methods: [
            {
                name: 'setChainParams',
                call: 'test_setChainParams',
                params: 1,
                outputFormatter: web3.extend.formatters.formatOutputBool
            },
            {
                name: 'mineBlocks',
                call: 'test_mineBlocks',
                params: 1,
                inputFormatter: web3.extend.utils.formatInputInt,
                outputFormatter: web3.extend.formatters.formatOutputBool
            }]
    }
);

Promise.all([
    web3.eth.personal.newAccount('password'),
    web3.eth.personal.newAccount('password')
]).then(setupAccounts);

var acct0, acct1;

function setupAccounts(x)
{
    web3.eth.getAccounts()
        .then(function(accountList){
            acct0 = accountList[0];
            acct1 = accountList[1];
        })
        .then(setupChain);
}

function setupChain()
{
    console.log("ACCT0 = ", acct0);
    console.log("ACCT1 = ", acct1);

    params.accounts[acct0] = { wei: '1606938044258990275541962092341162602522202993782792835301375'};

    web3.test.setChainParams(params)
        .then(function(x) {

            web3.eth.getBalance(acct0).then(console.log);
            web3.eth.getBalance(acct1).then(console.log);

            web3.eth.personal.unlockAccount(acct0, 'password', 100000)
                .then(function(x){
                    web3.eth.sendTransaction({from: acct0, to: acct1, value:1000}).then(console.log)
                        .then(console.log)
                        .catch(console.error)
                });

            web3.test.mineBlocks(10);
        })
}