测试结束后摩卡挂了

我在nodejs中运行mocha,测试一个异步函数,我没有忘记调用done,但是测试通过后,mocha就挂在那里,什么都不等待。甚至是我为之设置的功能 after() 已经完成了,但是直到我按ctrl+c,摩卡才退出。

代码如下:

describe("tests the user_handler", () => {
  beforeEach(resetDB);
  after(resetDB);

  it("returns null when searching for a user with an id that does not exists", (done) => {
    userHandler.findUserById( {user_id: "U-1234567"} )
      .then((result) => {
        expect(result).to.be.null;
        done()
      })
  })
})

这里是输出:

tomk@tomk-Latitude-7480 ~/workspace/fundme/server (login_with_github) $ npm test

> fundme-server@1.0.0 test /home/tomk/workspace/fundme/server
> mocha tests/*.spec.js



  tests the user_handler
resetDB called
resetDB finished
    ✓ returns null when searching for a user with an id that does not exists
resetDB called
resetDB finished


  1 passing (64ms)

^CTerminated

如果它是相关的(尽管我不这么认为),被测试的函数使用的是 mysqlConnectionPool 从 mysql2 图书馆

这是 resetDB 我使用的函数 beforeEach 和 after 以下内容:

function resetDB() {
  console.log("resetDB called")
  command =
    "mysql" +
    " --defaults-extra-file=" + mysql_conf_file +
    " --host " + process.env['MYSQL_HOSTNAME'] +
    " -D fundme < " + testing_db_file_location;
  cp.execSync(command);
  console.log("resetDB finished")
}

对我可能忘记的事情有什么想法吗?