openzeppelin-contracts/test/payment/PullPayment.test.js

const { balance, ether } = require('openzeppelin-test-helpers');

const PullPaymentMock = artifacts.require('PullPaymentMock');

contract('PullPayment', function ([_, payer, payee1, payee2]) {
  const amount = ether('17');

  beforeEach(async function () {
    this.contract = await PullPaymentMock.new({ value: amount });
  });

  it('can record an async payment correctly', async function () {
    await this.contract.callTransfer(payee1, 100, { from: payer });
    (await this.contract.payments(payee1)).should.be.bignumber.equal('100');
  });

  it('can add multiple balances on one account', async function () {
    await this.contract.callTransfer(payee1, 200, { from: payer });
    await this.contract.callTransfer(payee1, 300, { from: payer });
    (await this.contract.payments(payee1)).should.be.bignumber.equal('500');
  });

  it('can add balances on multiple accounts', async function () {
    await this.contract.callTransfer(payee1, 200, { from: payer });
    await this.contract.callTransfer(payee2, 300, { from: payer });

    (await this.contract.payments(payee1)).should.be.bignumber.equal('200');

    (await this.contract.payments(payee2)).should.be.bignumber.equal('300');
  });

  it('can withdraw payment', async function () {
    const balanceTracker = await balance.tracker(payee1);

    await this.contract.callTransfer(payee1, amount, { from: payer });
    (await this.contract.payments(payee1)).should.be.bignumber.equal(amount);

    await this.contract.withdrawPayments(payee1);

    (await balanceTracker.delta()).should.be.bignumber.equal(amount);
    (await this.contract.payments(payee1)).should.be.bignumber.equal('0');
  });
});