css/selectors/invalidation/not-pseudo-containing-sibling-relationship-in-has.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Selectors Test: :has(:not()) invalidation for sibling change</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel="help" href="https://drafts.csswg.org/selectors/#relational">
<style>
  #test-container > div { background-color: green; }
  #target1:has(:not(.item, :nth-child(3))) { background-color: red; }
  #target2:has(:not(.item, :nth-last-child(3))) { background-color: red; }
</style>
<div id="test-container">
  <div id="target1">
    <div class="item"></div>
    <div id="item1">This text should have a green background</div>
  </div>
  <div id="target2">
    <div id="item2">This text should have a green background</div>
    <div class="item"></div>
  </div>
</div>
<script>
  test(() => {
    assert_equals(getComputedStyle(target1).backgroundColor, "rgb(255, 0, 0)");
    assert_equals(getComputedStyle(target2).backgroundColor, "rgb(255, 0, 0)");
  }, "Initially red");

  function insertDivItemBefore(item) {
    let div = document.createElement("div");
    div.classList.add("item");
    item.parentElement.insertBefore(div, item);
  }

  function insertDivItemAfter(item) {
    let div = document.createElement("div");
    div.classList.add("item");
    item.parentElement.append(div, item.nextSibling);
  }

  test(() => {
    insertDivItemBefore(item1);
    assert_equals(getComputedStyle(target1).backgroundColor, "rgb(0, 128, 0)");
  }, ":nth-child() enclosed by :not() matching after insertion");

  test(() => {
    insertDivItemAfter(item2);
    assert_equals(getComputedStyle(target2).backgroundColor, "rgb(0, 128, 0)");
  }, ":nth-last-child() enclosed by :not() matching after insertion");
</script>