在Mocha和Chai中测试Promise

npm install mocha chai --save-dev

const chai = require('chai');
const assert = chai.assert;
const expect = chai.expect;

describe('Promise', function() {
  it('should resolve with the correct value', function() {
    return new Promise(function(resolve, reject) {
      resolve('success');
    })
    .then(function(result) {
      assert.equal(result, 'success');
    });
  });

  it('should reject with the correct error', function() {
    return new Promise(function(resolve, reject) {
      reject(new Error('failure'));
    })
    .catch(function(error) {
      expect(error.message).to.equal('failure');
    });
  });
});

mocha test.js