{
  "with a throwing getter": (() => {
    const v = {};
    Object.defineProperty(v, "x", {
      get: () => {
        throw new Error("nope");
      },
      enumerable: true,
    });
    return v;
  })(),
}

--

with a throwing getter:
{x:/unconvertible("nope")}
{
  x: /unconvertible("nope")
}
{
  x: {
    "/unconvertible": "nope"
  }
}