npm测试-必须使用导入加载ES模块-但我以为我是(节点12)

我的文件都是 .mjs

我有 fizz_buzz.mjs 和 test/fizz_buzz.spec.mjs

import { fizzBuzz } from '../fizz_buzz'

npm test

> mocha test/**/*.spec.mjs                                                                                                                              

/home/durrantm/Dropbox/90_2019/work/code/js/mocha_chai_bdd_tdd_exercises/node_modules/yargs/yargs.js:1163                                               
      else throw err                                                                                                                                    
           ^                                                                                                                                            

Error [ERR_REQUIRE_ESM]: Must use import to load ES Module: /home/durrantm/Dropbox/90_2019/work/code/js/mocha_chai_bdd_tdd_exercises/test/fizz_buzz.spec
.mjs                                                                                                                                                    
    at Object.Module._extensions..mjs (internal/modules/cjs/loader.js:1025:9)                                                                          
    at Module.load (internal/modules/cjs/loader.js:811:32)
    at Function.Module._load (internal/modules/cjs/loader.js:723:14)
    at Module.require (internal/modules/cjs/loader.js:848:19)

嘶嘶作响.mjs 目前只有:

$ cat fizz_buzz.mjs 
export function fizzBuzz() {
  return true
}

仅供参考 package .json

"scripts": {
  "test": "mocha test/**/*.spec.mjs"
},

万一这就是问题所在?

$ mocha test/**/*.spec.mjs --experimental-modules 但同样的错误