deno/cli/tests/testdata/workers/parent_read_check_worker.js

const worker = new Worker(
  new URL("./read_check_granular_worker.js", import.meta.url).href,
  { type: "module", deno: { permissions: "none" } },
);

onmessage = ({ data }) => {
  worker.postMessage(data);
};

worker.onmessage = ({ data }) => {
  postMessage(data);
};