ReferenceError: address is not defined

Question

Truffle v5.0.5 (core: 5.0.5)
Solidity v0.5.0 (solc-js)
Node v10.15.1

ReferenceError: address is not defined.

const ApprovalContracts = artifacts.require('../../contracts/ApprovalContracts.sol'); // Pulls in my smart contract // the accounts are the 10 dummie ones
// the require pulls in the smart contract // the artifacts pulls in our code

contract ('ApprovalContracts', function (accounts) { // These are the accounts stored locally in the server the address
    //tests in javascript part of the contract //setup a contract and getting back the approver //takes a deposit im going to look and see what the balance is
    it('initiates contract', async function() { 
        const contract = await ApprovalContracts.deployed();
        const approver = await contract.approver.call(); 
        assert.equal(approver, 0xc7780C9521C2C2abED69f0D65BEbF9794C55ae94, "approvers don't match");
    });

    it('takes a deposit', async function() {
        const balance = await web3.eth.getBalance(address.contract);  -----> ReferenceError: address is not defined
        const expected = web3.utils.toBN(1e+18);
        assert.equal(balance.toString(), expected.toString(), "amount did not match");
    });
});

Any advice I would be much appreciated.

const balance = await web3.eth.getBalance(address.contract);

Answer 1

You have two problems:

• web3.eth.getBalance() returns an promiEvent object, to obtain the expected value you need to await for it
• Javascript doesn't support large numbers, so values are wrapped in BN objects, and assert doesn't know how to compare those objects against numbers

One solution is converting BN objects to strings to compare them.

const balance = await web3.eth.getBalance(contract.address);
const expected = web3.utils.toBN(1e+18);
assert.equal(balance.toString(), expected.toString(), "amount did not match");

Answer 2

FWIW, I had the exact same issue and got my test to pass like this:

// Truffle v5.1.23 (core: 5.1.23)
// Solidity - ^0.4.18 (solc-js)
// Node v12.14.1
// Web3.js v1.2.1


contract('ApprovalContract', function(accounts) {

  ...

  it('takes a deposit', async function () {
    const contract = await ApprovalContract.deployed();
    const balance = 1e+18;
    const expected = web3.utils.toBN(1e+18);
    await contract.deposit(accounts[1], {
      value: balance, from: accounts[0]
    });
    assert.equal(balance.toString(), expected.toString(), "amount did not match");
  });

});

I'm a total blockchain noob and am JUST starting to ramp up on it, so I can't say my test represents a real-world blockchain use case. But things pass.

Also, this code is from a lynda.com Ethereum course: it's good but it's also almost two years old at the time of this comment and has only been updated once since then. So as that tutorial says to do an npm install -g truffle, I'm assuming that the tutorial was using a truffle version older than the version we downloaded while going through things, and that caused enough conflict for the tests to initially fail.

Answer 3

const balance = await web3.eth.getBalance(address.contract);

change this to

const balance = await web3.eth.getBalance(contract.address);