Monkey-patch Promise constructor

Just as an exercise, I tried monkey-patching the Promise constructor, like so:

const pconstructor = global.Promise;
global.Promise = function (fn1) {
  this.foo = 'bar';
  pconstructor.call(this,fn1);
};

global.Promise.resolve = pconstructor.resolve;

however, I get an error when I call

Promise.resolve();

=>

TypeError: [object Object] is not a promise

Anyone know how to monkey-patch a constructor like this, properly?

via Alexander Mills