GuessTheNewNumberChallenge.test.js

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

contract('GuessTheNewNumberChallenge', ([account]) => {
  it('should be completed', async () => {
    let challenge = await GuessTheNewNumberChallenge.new({value: web3.toWei(1, 'ether')});

    assert(
      await challenge.isComplete() === true,
      'Challenge has not been completed!'
    );
  });
});