layout/style/test/test_flexbox_focus_order.html
author Sandor Molnar <smolnar@mozilla.com>
Fri, 24 Sep 2021 00:43:42 +0300
changeset 593102 4eda9eb8926bdd50f4b80128ce3475eb7c6d9a4d
parent 469640 c9c0c6f2eed54a187e124942e53c3660b4cf17d8
permissions -rw-r--r--
Merge autoland to mozilla-central. a=merge

<!DOCTYPE html>
<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=812687
-->
<head>
  <title>Test for Bug 812687: focus order of reordered flex items</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <script src="/tests/SimpleTest/EventUtils.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
  <style>
    .container { display: flex; }

    #focus1 { background: yellow;    }
    #focus2 { background: lightgray; }
    #focus3 { background: orange;    }
    #focus4 { background: lightblue; }
    #focus5 { background: pink;      }
  </style>
</head>
<body>
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=812687">Mozilla Bug 812687</a>
<p id="display">
  <a href="#" id="beforeContainer">Link before container</a>
  <!-- This flex container's children are reordered visually with the "order"
       CSS property, but their focus order (when tabbing through them) should
       match their DOM order. So, #focus1 should receive focus before the other
       flex items, even though it isn't visually the first flex item.  And so
       on, up to #focus5, which is visually first (due to its negative "order"
       value) but should be focused last (due to being last in the DOM). -->
  <div class="container">
    <a href="#" id="focus1">1</a>
    <div><a href="#" id="focus2">2</a></div>
    <div style="order: 100"><a href="#" id="focus3">3</a></div>
    <div><a href="#" id="focus4">4</a></div>
    <a href="#" id="focus5" style="order: -1">5</a>
  </div>
</p>
<div id="content" style="display: none"></div>

<pre id="test">
<script class="testbody" type="text/javascript">

/** Test for Bug 812687 **/

const gExpectedFocusedIds = [
  "focus1",
  "focus2",
  "focus3",
  "focus4",
  "focus5"
];

function doTest() {
  // First, we focus something just before the flex container:
  document.getElementById('beforeContainer').focus();
  is(document.activeElement, document.getElementById('beforeContainer'),
     "explicitly-focused link should gain focus");

  // And then we advance focus across the focusable things in the flex container
  // and check that we traverse them in the expected order:
  for (let expectedId of gExpectedFocusedIds) {
    synthesizeKey("KEY_Tab");
    is(document.activeElement, document.getElementById(expectedId),
       "expecting element '#" + expectedId + "' to be focused");
  }

  SimpleTest.finish();
}

// Before we start, we have to bump Mac to make its 'tab'-key focus behavior
// predicatble:
function begin() {
  SpecialPowers.pushPrefEnv({ set: [[ "accessibility.tabfocus", 7 ]] }, doTest);
}

SimpleTest.waitForExplicitFinish();
addLoadEvent(begin);

</script>
</pre>
</body>
</html>