old_contents: const chai = require('chai');
  const assert = chai.assert;
  const ST = require('../lib/spacetime');
  const $ = require('jquery');
  
  describe('my test suite', function () {
      it('should work', function () {
          assert(true);
      });
  
      it('should add two plus two', function () {
          let four = 2 + 2;
          assert.equal(four,4);
      });
  
      it('should be deep equal', function (){
          let x = [1,2,3,];
          assert.deepEqual(x,[1,2,3]);
          //Deep equal checks order and content of arrays
      });
  });
  
new_contents: "use strict";
  const chai   = require('chai');
  const assert = chai.assert;
  const ST     = require('../lib/spacetime');
  const $      = require('jquery');
  
  describe('space-time functionality', function () {
      it('should have properties', function () {
          let canvas = {
                          width: 800,
                          height: 500
                      };
          let game   = {
                          asteroidQuantity: 5,
                          alienQuantity: 2
                      };
  
          let spaceTime = new ST(canvas, null, game);
  
          assert.equal(spaceTime.asteroids.length, 5);
          assert.equal(spaceTime.aliens.length, 2);
          assert.equal(spaceTime.lasers.length, 0);
          assert.equal(spaceTime.alienLasers.length, 0);
          assert.equal(spaceTime.shields.length, 0);
          assert.equal(spaceTime.mines.length, 0);
      });
  });
  
subject: Test spaceTime's initial properties