chromium/third_party/blink/web_tests/regress/regress-1239910-device.html

<title>Regression tests for crbug.com/1239910 - requestDevice part</title>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>

<script>
  promise_test(async (test) => {
    // {navigator.gpu} is required for this test, but it only exists when
    // WebGPU is enabled. Early out if it isn't present. Also early out if no
    // adapter could be created.
    const adapter = await navigator.gpu?.requestAdapter();
    if (!adapter) {
       test.done();
       return;
    }

    var first_time = true;
    Object.prototype.__defineGetter__("then", function() {
      if (!first_time) {
        return;
      }
      first_time = false;

      // Request a lot of devices to force an reallocation of the map that
      // translate request IDs to the request's data.
      for (var i = 0; i < 10; i++) {
        adapter.requestDevice();
      }
    });

    // Request a single device. When it gets resolved the browser will try to
    // access Promise.then that will call the function above, invalidating the
    // iterator into the request map. The regression was that the iterator was
    // used after .then is accessed.
    adapter.requestDevice();

    test.done();
  }, 'Regression test for crbug.com/1239910 - requestDevice part');
</script>