从npm本地依赖导入es6模块而不转换babel

Question

我有一个用esul文件编写的主项目：

var source = require('vinyl-source-stream');
var gulp = require('gulp');
var watchify = require('watchify');
var browserify = require('browserify');
var streamify = require('gulp-streamify');

var sources = ['./src/main.js'];
var destination = '../../public/compiled';

var standalone = 'Round';

gulp.task('dev', function() {
  return browserify('./src/main.js', {
    standalone: standalone
  }).transform('babelify',
               { presets: ["es2015"],
                 plugins: ['add-module-exports'] })
    .bundle()
    .pipe(source('round.js'))
    .pipe(gulp.dest(destination));
});

我在package.json

中有这个本地依赖

{
  "dependencies": {
    "game": "file:///home/ubuntu/ui/game",
  },
}

game模块用es6编写。我希望我的主项目在es6中安装和导入该模块并进行转换。但我得到了error：

'import' and 'export' may appear only with 'sourceType: module' #103