code: function batchMethod (obj, method) {
    const descriptor = Object.getOwnPropertyDescriptor(obj, method)
    if (descriptor) {
      const newDescriptor = Object.assign({}, descriptor, {
        set (value) {
          return descriptor.set.call(this, batchFn(value))
        }
      })
      Object.defineProperty(obj, method, newDescriptor)
    }
  }
docs: batches obj.onevent = fn like calls