<!doctype html>
<title>CSS Shadow Parts - Exporting multiple shadow parts</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel="author" href="mailto:emilio@crisal.io" title="Emilio Cobos Álvarez">
<link rel="author" href="https://mozilla.org" title="Mozilla">
<link rel="help" href="https://drafts.csswg.org/css-shadow-parts/">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1618509">
<style>
::part(inner-part) {
  color: red;
  background: blue;
  width: 100px;
  height: 100px;
}
::part(inner-part-alias) {
  color: green;
}
.change-1::part(inner-part) {
  background: green;
}

.change-2::part(inner-part-alias) {
  color: blue;
}
</style>
<div id="outer"></div>
<script>
test(function() {
  let outer = document.getElementById("outer");
  outer.attachShadow({ mode: "open" }).innerHTML = `
    <div exportparts="inner-part, inner-part: inner-part-alias"></div>
  `;

  let inner = outer.shadowRoot.querySelector("div");
  inner.attachShadow({ mode: "open" }).innerHTML = `
    <div part="inner-part"></div>
  `;

  let innerPart = inner.shadowRoot.querySelector("div");
  assert_equals(
    getComputedStyle(innerPart).color,
    "rgb(0, 128, 0)",
    "color should be green from ::part(inner-part-alias) rule"
  );
  assert_equals(
    getComputedStyle(innerPart).backgroundColor,
    "rgb(0, 0, 255)",
    "background should be blue from ::part(inner-part) rule"
  );

  outer.classList.add("change-1");
  assert_equals(
    getComputedStyle(innerPart).color,
    "rgb(0, 128, 0)",
    "color should be green from ::part(inner-part-alias) rule"
  );
  assert_equals(
    getComputedStyle(innerPart).backgroundColor,
    "rgb(0, 128, 0)",
    "background should be green from .change-1::part(inner-part) rule"
  );

  outer.classList.add("change-2");
  assert_equals(
    getComputedStyle(innerPart).color,
    "rgb(0, 0, 255)",
    "color should be blue from .change-2::part(inner-part-alias) rule"
  );
  assert_equals(
    getComputedStyle(innerPart).backgroundColor,
    "rgb(0, 128, 0)",
    "background should be green from .change-1::part(inner-part) rule"
  );
}, "Forwarding part under multiple names should work");
</script>
