模拟实现 instanceof

function fakeInstanceof(left, right) {
  const rightProto = right.prototype
  // eslint-disable-next-line no-proto
  let leftProto = left.__proto__
  // eslint-disable-next-line no-constant-condition
  while (true) {
    if (leftProto === null) {
      return false
    }
    if (leftProto === rightProto) {
      return true
    }
    // eslint-disable-next-line no-proto
    leftProto = leftProto.__proto__
  }
}