text: //load chai assertion library
  const chai = require("chai");
  const expect = chai.expect;
  const asserttype = require("chai-asserttype");
  chai.use(asserttype);
  
  //load calculator code
  var Calculator = require("../Calculator");
  var calc = new Calculator();
  
  describe("Calculator Tests (Chai)", function () {
    it("Adds 1 and 2", function () {
      expect(calc.add(1, 2)).to.be.equal(3);
    });
  
    it("Add Allows one parameter", function () {
      expect(calc.add(1)).to.be.equal(1);
    });
  
    it("Add Allows no parameters", function () {
      expect(calc.add()).to.be.equal(0);
    });
  
    it("Add turns strings to zeros", function () {
      expect(calc.add("frog", "toad")).to.be.number();
    });
  });
  