<!DOCTYPE html>
<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="/resources/testdriver-actions.js"></script>
<script src="resources/shadow-dom.js"></script>
<script src="resources/focus-utils.js"></script>
<div id='log'></div>
<p>
  document tree: [i0 -> [x-foo]]<br>
  x-foo's shadow tree: [j1 -> j2 -> [s1]]<br>
  <b>slot #s1: [k1 -> [x-bar] -> k0 -> [s2] -> [s3]]</b><br>
  x-bar's shadow tree: [m1 -> m2]<br>
  slot #s2: [i1 -> i2]<br>
  <b>slot #s3: [l1]<b><br><br>
  <b>v1 ideal nav forward:  [i0 -> j1 -> j2 -> k1 -> x-bar -> m1 -> m2 -> k0 -> i1 -> i2 -> l1]</b><br>
</p>

<input id='i0' tabindex=0 value='i0'>
<div id='x-foo'>
  <input id='i2' slot='s2' tabindex=2 value='i2'>
  <input id='i1' slot='s2' tabindex=1 value='i1'>
  <template data-mode='open'>
    <input id='j1' tabindex=1 value='j1'>
    <slot id='s1' name='s1'> <!-- This slot does not have any assigned elements -->
      <input id='k0' tabindex=0 value='k0'>
      <input id='k1' tabindex=1 value='k1'>
      <slot id='s2' name='s2'>
        <input id='should-be-ignored'>
      </slot>
      <slot id='s3' name='s3'> <!-- This slot does not have any assigned elements -->
        <input id='l1' value='l1'>
      </slot>
      <div id='x-bar' tabindex=2>
        <template data-mode='open'>
          <input id='m2' value='m2' tabindex=2>
          <input id='m1' value='m1' tabindex=1>
        </template>
      </div>
    </slot>
    <input id='j2' tabindex=2 value='j2'>
  </template>
</div>

<script>
'use strict';

promise_test(async () => {
  let xfoo = document.getElementById('x-foo');
  convertTemplatesToShadowRootsWithin(xfoo);

  let elements = [
      'i0',
      'x-foo/j1',
      'x-foo/j2',
      'x-foo/k1',
      'x-foo/x-bar',
      'x-foo/x-bar/m1',
      'x-foo/x-bar/m2',
      'x-foo/k0',
      'i1',
      'i2',
      'x-foo/l1'
    ];

    await assert_focus_navigation_forward(elements);
    elements.reverse();
    await assert_focus_navigation_backward(elements);
}, 'Focus should jump to fallback elements when a slot does not have any assigned nodes.');
</script>
