old_contents: 'use strict';
  
  var path = require('path');
  var helpers = require('yeoman-generator').test;
  
  describe('basic project generator', function () {
    beforeEach(function (done) {
      helpers.run(path.join( __dirname, '../app'))
        .inDir(path.join( __dirname, './tmp'))
        .on('end', done);
    });
  
    it('creates expected default files', function () {
      var expected = [
        '.gitignore',
        '.editorconfig',
        'readme.md',
        'license',
      ];
  
      helpers.assertFiles(expected);
    });
  });
  
new_contents: 'use strict';
  
  var path = require('path');
  var helpers = require('yeoman-generator').test;
  
  describe('basic project generator', function () {
    beforeEach(function (done) {
      helpers.run(path.join( __dirname, '../app'))
        .inDir(path.join( __dirname, './tmp'))
        .on('end', done);
    });
  
    it('creates expected default files', function () {
      var expected = [
        '.gitignore',
        '.editorconfig',
        'readme.md',
        'license',
      ];
  
      helpers.assertFile(expected);
    });
  });
  
subject: Switch to helpers.assertFile - assertFiles is deprecated