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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /dom/nodes/DocumentFragment-getElementById.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<meta charset="utf-8">
<title>DocumentFragment.prototype.getElementById</title>
<link rel="author" title="Domenic Denicola" href="mailto:d@domenic.me">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<template>
<div id="bar">
<span id="foo" data-yes></span>
</div>
<div id="foo">
<span id="foo"></span>
<ul id="bar">
<li id="foo"></li>
</ul>
</div>
</template>
<script>
"use strict";
test(() => {
assert_equals(typeof DocumentFragment.prototype.getElementById, "function", "It must exist on the prototype");
assert_equals(typeof document.createDocumentFragment().getElementById, "function", "It must exist on an instance");
}, "The method must exist");
test(() => {
assert_equals(document.createDocumentFragment().getElementById("foo"), null);
assert_equals(document.createDocumentFragment().getElementById(""), null);
}, "It must return null when there are no matches");
test(() => {
const frag = document.createDocumentFragment();
frag.appendChild(document.createElement("div"));
frag.appendChild(document.createElement("span"));
frag.childNodes[0].id = "foo";
frag.childNodes[1].id = "foo";
assert_equals(frag.getElementById("foo"), frag.childNodes[0]);
}, "It must return the first element when there are matches");
test(() => {
const frag = document.createDocumentFragment();
frag.appendChild(document.createElement("div"));
frag.childNodes[0].setAttribute("id", "");
assert_equals(
frag.getElementById(""),
null,
"Even if there is an element with an empty-string ID attribute, it must not be returned"
);
}, "Empty string ID values");
test(() => {
const frag = document.querySelector("template").content;
assert_true(frag.getElementById("foo").hasAttribute("data-yes"));
}, "It must return the first element when there are matches, using a template");
</script>