src/third_party/web_platform_tests/fetch/nosniff/worker.html

<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<div id=log></div>
<script>
  var workers = [],
      fails = ["", "?type=", "?type=x", "?type=x/x"],
      passes = ["?type=text/javascript", "?type=text/ecmascript", "?type=text/ecmascript;yay"]

  fails.forEach(function(urlpart) {
    async_test(function(t) {
      var w = new Worker("resources/worker.py" + urlpart)
      w.onmessage = t.unreached_func("Unexpected message event")
      w.onerror = t.step_func_done(function(){})
      workers.push(w) // avoid GC
    }, "URL query: " + urlpart)
  })

  passes.forEach(function(urlpart) {
    async_test(function(t) {
      var w = new Worker("resources/worker.py" + urlpart)
      w.onmessage = t.step_func_done(function(e){
        assert_equals(e.data, "hi")
      })
      w.onerror = t.unreached_func("Unexpected error event")
      workers.push(w) // avoid GC
    }, "URL query: " + urlpart)
  })
</script>