chromium/third_party/blink/web_tests/external/wpt/xhr/thrown-error-in-events.html

<!DOCTYPE html>
<title>Errors thrown in XMLHttpRequest events get to window.onerror</title>
<link rel="author" title="Domenic Denicola" href="mailto:[email protected]">

<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<script>
"use strict";

setup({ allow_uncaught_exception: true });

promise_test(() => {
  const error = new Error("oh no!");
  let resolve;

  window.addEventListener("error", event => {
    assert_equals(event.error, error);
    resolve();
  });

  const xhr = new window.XMLHttpRequest();

  xhr.addEventListener("load", () => {
    throw error;
  });

  xhr.open("GET", location.href);
  xhr.send();

  return new Promise(r => {
    resolve = r;
  });

}, "errors thrown in XMLHttpRequest's load event (using addEventListener) goes to window.onerror");

promise_test(() => {
  const error = new Error("oh no 2!");
  let resolve;

  window.addEventListener("error", event => {
    assert_equals(event.error, error);
    resolve();
  });

  const xhr = new window.XMLHttpRequest();

  xhr.onload = () => {
    throw error;
  };

  xhr.open("GET", location.href);
  xhr.send();

  return new Promise(r => {
    resolve = r;
  });

}, "errors thrown in XMLHttpRequest's load event (using onload) goes to window.onerror");
</script>