storage-access-api/storageAccess.testdriver.sub.html

<!DOCTYPE html>
<head>
  <title>TestDriver - Set Storage Access Command Tests</title>
  <script src="/cookies/resources/cookie-helper.sub.js"></script>
  <script src="/resources/testharness.js"></script>
  <script src="/resources/testharnessreport.js"></script>
  <script src="/resources/testdriver.js"></script>
  <script src="/resources/testdriver-vendor.js"></script>
  <script src="helpers.js"></script>
</head>
<body>
  <script>
    "use strict";

    // Use a different domain so that the cookie is cross-site.
    const wwwAlt = "https://{{hosts[alt][www]}}:{{ports[https][0]}}";

    promise_test(async t => {
      await MaybeSetStorageAccess("*", "*", "blocked");
      t.add_cleanup(async () => {
        await test_driver.delete_all_cookies();
        await MaybeSetStorageAccess("*", "*", "allowed");
      });

      const responder_html = `${wwwAlt}/storage-access-api/resources/script-with-cookie-header.py?script=embedded_responder.js`;
      const frame = await CreateFrame(responder_html);

      assert_false(await CanFrameWriteCookies(frame), "Cross-site iframe should not be allowed to write cookies via document.cookie.");
    });
  </script>
</body>