denoland-deno/cli/tests/testdata/workers/permissions_blob_local.ts

// This file doesn't really exist, but it doesn't matter, a "PermissionsDenied" error should be thrown.
const code = `import "file:///${
  Deno.build.os == "windows" ? "C:/" : ""
}local_file.ts";`;
const blob = new Blob([code]);
new Worker(URL.createObjectURL(blob), { type: "module" });