基于 Mocha 运行测试用例，使用断言库 Chai

PS E:\wwwroot\refactoring> npm install chai

added 8 packages, and audited 86 packages in 11s

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import {Province} from '../4/modules/province.js';
import chai from 'chai';

function sampleProvinceData() {
    return {
        name: "Asia",
        producers: [{name: "Byzantium", cost: 10, production: 9}, {
            name: "Attalia",
            cost: 12,
            production: 10
        }, {name: "Sinope", cost: 10, production: 6},],
        demand: 30,
        price: 20
    };
}

var expect = chai.expect;
describe('province', function() {
    it('shortfall', function() {
        const asia = new Province(sampleProvinceData());
        expect(asia.shortfall).equal(5);
    });
    it('profit', function() {
        const asia = new Province(sampleProvinceData());
        expect(asia.profit).equal(230);
    });
});

PS E:\wwwroot\refactoring> npm test

> test
> mocha



  province
    √ shortfall
    √ profit


  2 passing (13ms)