wallet.js

var wallet = artifacts.require("./MyWallet.sol");

var receivedProposal = function (walletInstance, from, to) {
  return new Promise((resolve, reject) => {
    var event = walletInstance.proposalReceived({from: from, to: to}, {fromBlock: 0, toBlock: "latest"});

    event.watch(function(error, response) {
      event.stopWatching();
      
      if (error) {
        return reject(error);
      }
      else {
        proposal_id = response.args._counter.toNumber();
        return resolve(proposal_id);
      }
    });
  })
}

contract("MyWallet", function(accounts) {
    // Wallet has 10 ethers
    it('should be possible to put money inside', async function() {
      let walletInstance = await wallet.deployed();
      await walletInstance.sendTransaction({
        value: web3.toWei(10, 'ether'), address: walletInstance.address, from: accounts[0]
      });

      assert.equal(web3.eth.getBalance(walletInstance.address).toNumber(), web3.toWei(10, 'ether'), 'The Balance is the same');
    });

    // spendMoneyOn
    it('should be possible to get money back as the owner', async function() {
      const amountToSend = web3.toWei(5, 'ether');
      let walletInstance = await wallet.deployed();
      let balanceBeforeSend = await web3.eth.getBalance(walletInstance.address).toNumber();

      await walletInstance.spendMoneyOn(accounts[0], amountToSend, "Because I'm the owner", {from: accounts[0]});

      const balanceAfterSend = await web3.eth.getBalance(walletInstance.address).toNumber();
      assert.equal(balanceBeforeSend - amountToSend, balanceAfterSend, 'Balance is now 5 ether less than before');
    });

    // spendMoneyOn + confirmProposal
    it('should be possible to propose and confirm spending money', async function() {
      let walletInstance = await wallet.deployed();
      await walletInstance.spendMoneyOn(accounts[1], web3.toWei(5,'ether'), "Because I need money", {from: accounts[1]});

      assert.equal(web3.eth.getBalance(walletInstance.address).toNumber(), web3.toWei(5, 'ether'), 'Balance is 5 ether less than before');

      let proposal_id = await receivedProposal(walletInstance, accounts[0], accounts[1]);

      await walletInstance.confirmProposal(proposal_id, {from: accounts[0]})

      assert.equal(web3.eth.getBalance(walletInstance.address).toNumber(), web3.toWei(0, 'ether'), 'Balance is 5 ether less than before');
    });
});