HTMLTableElement.prototype.rows does not reflect reality until length called

I wasn’t able to reproduce this immediately in a clean test case to share, but I stumbled upon an issue where table.deleteRow(0) does not change table.rows indices until table.rows.length is accessed.

Took me a while to understand that this was happening. A kind of a heisenbug.

[TimothyGu]

Yes it’s fixed! Did have to change the test to account for automatic tbody adding though:

const { JSDOM } = require(".");

const html = `
<table id="table">
  <tbody>
    <tr><td>Cell 1</td></tr>
    <tr><td>Cell 2</td></tr>
  </tbody>
</table>
<script>
  var table = document.getElementById('table');
  var tbody = table.children[0];

  console.log(table.rows[0].cells[0].textContent);

  var row1 = table.rows[0];
  tbody.removeChild(row1);
  tbody.appendChild(row1);

  console.log(table.rows[0].cells[0].textContent);

  table.rows.length;

  console.log(table.rows[0].cells[0].textContent);
</script>
`;

new JSDOM(html, { runScripts: 'dangerously' });

now outputs

Cell 1
Cell 2
Cell 2

as expected.

[domenic]

Should be fixed by https://github.com/tmpvar/jsdom/pull/1934, although we should add specific tests to confirm the caching isn’t messing us up somehow.