<!DOCTYPE html>
<title>:is() inside shadow pseudos</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel="help" href="https://drafts.csswg.org/selectors-4/#matches">
<link rel="help" href="https://drafts.csswg.org/css-scoping/#host-selector">
<link rel="help" href="https://drafts.csswg.org/css-scoping/#slotted-pseudo">
<div class="parent1"><div id="host1" class=a><p class=e>::slotted</p></div></div>
<div class="parent2"><div id="host2" class=b><p class=d>::slotted</p></div></div>
<div class="parent3"><div id="host3" class=c><p class=f>::slotted</p></div></div>
</div>
<script>
let shadow1 = host1.attachShadow({ mode: 'open' });
let shadow2 = host2.attachShadow({ mode: 'open' });
let shadow3 = host3.attachShadow({ mode: 'open' });
const html = `
<style>
* { color: blue; }
:host(:is(.a, .b)) b { color: green; }
:host-context(:is(.parent1, .parent2)) i { color: green; }
::slotted(:is(.e, .f)) { color: green; }
/* The following should not match: */
:host(:is(.z)) b { color: red; }
:host(:is(.a + .b)) b { color: red; }
:host-context(:is(.z)) i { color: red; }
:host-context(:is(.parent1 .parent2)) i { color: red; }
::slotted(:is(.z)) { color: red; }
::slotted(:is(.a > .b)) { color: red; }
</style>
<b>:host</b>
<i>:host-context</i>
<slot></slot>
`;
shadow1.innerHTML = html;
shadow2.innerHTML = html;
shadow3.innerHTML = html;
const getComputedColor = e => getComputedStyle(e).color;
const green = 'rgb(0, 128, 0)';
const blue = 'rgb(0, 0, 255)';
test(function() {
assert_equals(getComputedColor(shadow1.querySelector('b')), green);
assert_equals(getComputedColor(shadow2.querySelector('b')), green);
assert_equals(getComputedColor(shadow3.querySelector('b')), blue);
}, ':is() inside :host()');
test(function() {
assert_equals(getComputedColor(shadow1.querySelector('i')), green);
assert_equals(getComputedColor(shadow2.querySelector('i')), green);
assert_equals(getComputedColor(shadow3.querySelector('i')), blue);
}, ':is() inside :host-context()');
test(function() {
assert_equals(getComputedColor(document.querySelector('.e')), green);
assert_equals(getComputedColor(document.querySelector('.d')), blue);
assert_equals(getComputedColor(document.querySelector('.f')), green);
}, ':is() inside ::slotted()');
</script>