Blitz - WPT: host-part-003.html

wpt / css / css-shadow / part / host-part-003.html

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<!DOCTYPE html>
<title>CSS Shadow Parts - :host::part() not matching in inner scope</title>
<link rel="help" href="https://drafts.csswg.org/css-shadow/#part">
<link rel="help" href="https://drafts.csswg.org/css-shadow/#host-selector">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id="outer">
  <template shadowrootmode="open">
    <style>
      :host::part(x) {
        color: red;
      }
    </style>
    <div id="inner">
      <template shadowrootmode="open">
        <style>
          p { color: green; }
        </style>
        <p part="x">This should not be red</p>
      </template>
    </div>
  </template>
</div>
<script>
  test(() => {
    const part = outer.shadowRoot.querySelector("#inner").shadowRoot.querySelector("p");
    assert_equals(getComputedStyle(part).color, "rgb(0, 128, 0)");
  }, ":host::part() should only match when the part is in the same tree as the rule");
</script>