<!DOCTYPE html>
<html>
<head>
<title>CSS Shadow Parts - Double forward</title>
<meta href="mailto:[email protected]" rel="author" title="Fergal Daly">
<link href="http://www.google.com/" rel="author" title="Google">
<link href="https://drafts.csswg.org/css-shadow-parts/" rel="help">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="support/shadow-helper.js"></script>
</head>
<body>
<style>#c-e-outer::part(part-forwarded2) { color: green; }</style>
<script>installCustomElement("custom-element-inner", "custom-element-inner-template");</script>
<template id="custom-element-inner-template">
<style>span { color: red; }</style>
<span id="green_part" part="partp">This text</span>
</template>
<script>installCustomElement("custom-element-middle", "custom-element-middle-template");</script>
<template id="custom-element-middle-template"><custom-element-inner id="c-e-inner" exportparts="partp: part-forwarded1"></custom-element-inner></template>
<script>installCustomElement("custom-element-outer", "custom-element-outer-template");</script>
<template id="custom-element-outer-template"><custom-element-middle id="c-e-middle" exportparts="part-forwarded1: part-forwarded2"></custom-element-middle></template>
The following text should be green:
<custom-element-outer id="c-e-outer"></custom-element-outer>
<script>
"use strict";
const colorGreen = "rgb(0, 128, 0)";
test(function() {
const el = getElementByShadowIds(document, ["c-e-outer", "c-e-middle", "c-e-inner", "green_part"]);
assert_equals(window.getComputedStyle(el).color, colorGreen);
}, "Part in inner host is forwarded through the middle host for styling by document style sheet");
</script>
</body>
</html>
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