Node.js 为什么 instanceof 对 babelnode 下的 Error 子类的实例不起作用

在OS X上运行babel-node个版本6.1.18/Node版本5.1.0时，我发现instanceof操作符无法处理Error个子类的实例.这是为什么？同样的代码在浏览器中运行良好，请以my fiddle为例.

以下代码在浏览器中输出true，而在babel node 下则为false:

class Sub extends Error {
}

let s = new Sub()
console.log(`The variable 's' is an instance of Sub: ${s instanceof Sub}`)

我只能想象这是由于babel node 中的一个bug造成的，因为instanceof适用于Error以外的其他基类.

babelrc先生

{
  "presets": ["es2015"]
}

编译输出

这是babel 6.1.18编译的JavaScript:

'use strict';

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }

var Sub = (function (_Error) {
  _inherits(Sub, _Error);

  function Sub() {
    _classCallCheck(this, Sub);

    return _possibleConstructorReturn(this, Object.getPrototypeOf(Sub).apply(this, arguments));
  }

  return Sub;
})(Error);

var s = new Sub();
console.log('The variable \'s\' is an instance of Sub: ' + (s instanceof Sub));