<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Selectors Test: :has(:nth-child()) 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(.item:nth-child(3)) { background-color: red; }
#target2:has(.item:nth-last-child(3)) { background-color: red; }
#target3:has(.item:nth-child(3) > .child) { background-color: red; }
#target4:has(.item:nth-last-child(3) > .child) { background-color: red; }
</style>
<div id="test-container">
<div id="target1">
<div class="item" id="item1">FAIL if you see this text</div>
<div class="item"></div>
<div class="item">This text should have a green background</div>
</div>
<div id="target2">
<div class="item">This text should have a green background</div>
<div class="item"></div>
<div class="item" id="item2">FAIL if you see this text</div>
</div>
<div id="target3">
<div class="item" id="item3">FAIL if you see this text</div>
<div class="item"></div>
<div class="item">
<span class="child">This text should have a green background<span>
</div>
</div>
<div id="target4">
<div class="item">
<span class="child">This text should have a green background<span>
</div>
<div class="item"></div>
<div class="item" id="item4">FAIL if you see this text</div>
</div>
</div>
<script>
test(() => {
assert_equals(getComputedStyle(target1).backgroundColor, "rgb(255, 0, 0)");
assert_equals(getComputedStyle(target2).backgroundColor, "rgb(255, 0, 0)");
assert_equals(getComputedStyle(target3).backgroundColor, "rgb(255, 0, 0)");
assert_equals(getComputedStyle(target4).backgroundColor, "rgb(255, 0, 0)");
}, "Initially red");
test(() => {
item1.remove();
assert_equals(getComputedStyle(target1).backgroundColor, "rgb(0, 128, 0)");
}, ":nth-child() no longer matching after removal");
test(() => {
item2.remove();
assert_equals(getComputedStyle(target2).backgroundColor, "rgb(0, 128, 0)");
}, ":nth-last-child() no longer matching after removal");
test(() => {
item3.remove();
assert_equals(getComputedStyle(target3).backgroundColor, "rgb(0, 128, 0)");
}, ":nth-child() in non-subject no longer matching after removal");
test(() => {
item4.remove();
assert_equals(getComputedStyle(target4).backgroundColor, "rgb(0, 128, 0)");
}, ":nth-last-child() in non-subject no longer matching after removal");
</script>