inquirer-npm-name unit test initial changes but doesn't works. Needs verify if is necessary use of "mocha" or "chai" npm packages

test.js

describe('npm validation logic (inquirer `when` function)', function () {
  beforeEach(function () {
      askName2 = proxyquire('../lib', {
        'npm-name': function(name){
          return Promise.resolve(name == 'yo');
        }
    });
    
  it('ask question if npm name is taken', function (done) {
     this.inquirer.prompt.returns(Promise.resolve({name:'yo'}));

      return askName2(this.conf, this.inquirer).then(function(props){
        this.when = this.inquirer.prompt.getCall(0).args[0][1].when;
        console.log(this.when);
        this.when.call({name: 'yo'}).then(function(shouldAsk){
          assert.ok(shouldAsk);
          /*Problems with timeout to sincronize 
          * with async Promise here using done();
          * 
          * Verify the possibility of use the "mocha"
          * and/or "chai" npm packages
          */
          done(); 
        });
  });
});