const chai = require('chai');
const sinon = require('sinon');
let mod = require('../mathProject');
let math = require('./math.js');

// a)
// testing with 2 positive numbers
describe ('example1', function() {
    it('doDivision check if return correct result given 2 positive numbers, to 2 digits after the comma', function () {
        var a = math.doDivision(1,3);
        // we console log the outcome
        console.log(a)
        c = Math.ceil(a * 100)/100;
        // we console log the number rounded down to 2 digits after comma
        console.log(c)
        chai.expect(c).to.equal(0.34);
        chai.expect(c).to.be.a('number')
    });
});

// test with NaN
// if we don't add numbers to the function, excpecting NaN
// NaN will be accepted as a number
describe ('example2', function() {
    it('doDivision with nothing', function () {
        var a = math.doDivision();
        console.log(a);
        chai.expect(a).to.be.a('Number');
        chai.expect(a).to.be.NaN;
    });
});

// test with zero
// here we will assume an number divided by zero is Infinite
// Infinity will be accepted as a number
describe ('example3', function() {
    it('doDivision with zero', function () {
        var a = math.doDivision(999, 0);
        console.log(a);
        chai.expect(a).to.be.a('Number');
        chai.expect(a).to.equal(Infinity);
    });
});


// b)
// A single test asserting that the function returns the correct string ("a divided by b is result")
// given two positive numbers. Use a Stub/Fake (using the Sinon module) to replace the call to
// the doDivision function.

describe ('example4', function () {
    beforeEach(() => {
        var fakeCheck = sinon.fake.returns(true);
        sinon.replace(mod, 'doDivision', fakeCheck);
    });

    it('should always pass for stingifyDivision', function (done) {
        var answer = mod.stringifyDivision( 5, 6 );
            chai.expect(answer).to.equal('5 divided by 6 is true');
            done();
        });
});