JSFiddle - React, Tailwind, and code Playground

by Gajus Kuizinas

JavaScript

// The hash (#) and dot (.) symbols are a convention to mark if a method
// is called on an individual object or on the prototype. ".create" is
// called on the Cart prototype. #add are called on the derived objects.
 
describe('Cart', function () {
    var cart;
    beforeEach(function () {
        cart = Cart.create();
    });
    describe('.create', function () {
        it('must create a cart that contains 0 products', function () {
            var cart = Cart.create();
            expect(cart.numProducts()).toEqual(0);
        });
    });
    describe('#add', function () {
        it('must add a product to the cart', function () {
            var product = {};
            cart.add(product);
            expect(cart.doesContain(product)).toBeTruthy();
        });
    });
    describe('#doesContain', function () {
        it('must return false for a product that is not contained', function () {
            var product = {};
            cart.add({});
            expect(cart.doesContain(product)).toBeFalsy();
        });
    });
    describe('#grossPriceSum', function () {
        it('must return 0 for an empty cart', function () {
            expect(cart.grossPriceSum()).toBe(0);
        });
        it('must return price for a single product in the cart', function () {
            var product;
            product = {
                grossPrice: function () { return 0; }
            };
            spyOn(product, 'grossPrice').and.returnValue(10);
            cart.add(product);
            expect(cart.grossPriceSum()).toBe(10);
        });
        it('must return price for two products in the cart', function () {
            cart.add({grossPrice: function () { return 10; }});
            cart.add({grossPrice: function () { return 20; }});
            expect(cart.grossPriceSum()).toBe(30);
        });
    });
});