html/syntax/parsing/custom-element-reparenting.html - external/github.com/web-platform-tests/wpt - Git at Google

 <!DOCTYPE html>
 <meta charset="utf-8">
 <title>Parser element insertion when a custom element reaction reparents nodes</title>
 <link rel="help" href="https://html.spec.whatwg.org/multipage/parsing.html#insert-an-element-at-the-adjusted-insertion-location">
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 <script src="resources/adoption-agency-reparenting.js"></script>
 <body>
 <script>
 // The custom element constructor, and attributeChangedCallback for the token's
 // attributes, both run before the element is inserted. These are the cases
 // where the resulting tree stays well-formed; the cycle-inducing variants live
 // in custom-element-reparenting-*-cycle.html.

 promise_test(async t => {
   const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement {})<\/script><body><x-a><p>y</p></x-a>`);
   assert_equals(tree(iframe.contentDocument.body), `<x-a>[<p>["y"]]`);
 }, "Baseline: a custom element that does not reparent anything");

 promise_test(async t => {
   const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement { static get observedAttributes() { return ['x'] } attributeChangedCallback() { if (window.el) return; window.el = this; document.head.appendChild(this) } })<\/script><body><x-a x=1><p>y</p></x-a>`);
   const w = iframe.contentWindow, d = iframe.contentDocument;
   assert_equals(w.el.parentNode, d.head, "the custom element stayed where the callback put it");
   assert_equals(tree(d.body), ``, "the custom element was not also inserted into body");
   assert_equals(tree(w.el), `<p>["y"]`, "following content went into the custom element");
 }, "attributeChangedCallback gives the element a parent before it is inserted");

 promise_test(async t => {
   const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement { static get observedAttributes() { return ['x'] } attributeChangedCallback() { if (window.el) return; window.el = this; window.b = document.body; window.b.remove() } })<\/script><body><x-a x=1><p>y</p></x-a>`);
   const w = iframe.contentWindow, d = iframe.contentDocument;
   assert_equals(d.body, null, "the html element no longer has a body child");
   assert_equals(w.b.parentNode, null, "body stayed detached");
   assert_equals(tree(w.b), `<x-a>[<p>["y"]]`, "the element was inserted into the detached body");
 }, "attributeChangedCallback detaches the intended parent before the element is inserted");

 // A shadow root that does not contain the intended parent must not prevent the
 // insertion; this is what an over-broad cycle guard would break.
 promise_test(async t => {
   const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement { constructor() { super(); window.el = this; window.root = this.attachShadow({mode: 'open'}); window.root.appendChild(document.createElement('span')) } })<\/script><body><x-a><p>y</p></x-a>`);
   const w = iframe.contentWindow, d = iframe.contentDocument;
   assert_equals(tree(d.body), `<x-a>[<p>["y"]]`, "the element was inserted normally");
   assert_equals(w.root.firstChild.localName, "span", "its shadow root is untouched");
 }, "Custom element constructor attaches an unrelated shadow root");
 </script>
	<!DOCTYPE html>
	<meta charset="utf-8">
	<title>Parser element insertion when a custom element reaction reparents nodes</title>
	<link rel="help" href="https://html.spec.whatwg.org/multipage/parsing.html#insert-an-element-at-the-adjusted-insertion-location">
	<script src="/resources/testharness.js"></script>
	<script src="/resources/testharnessreport.js"></script>
	<script src="resources/adoption-agency-reparenting.js"></script>
	<body>
	<script>
	// The custom element constructor, and attributeChangedCallback for the token's
	// attributes, both run before the element is inserted. These are the cases
	// where the resulting tree stays well-formed; the cycle-inducing variants live
	// in custom-element-reparenting-*-cycle.html.

	promise_test(async t => {
	const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement {})<\/script><body><x-a><p>y</p></x-a>`);
	assert_equals(tree(iframe.contentDocument.body), `<x-a>[<p>["y"]]`);
	}, "Baseline: a custom element that does not reparent anything");

	promise_test(async t => {
	const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement { static get observedAttributes() { return ['x'] } attributeChangedCallback() { if (window.el) return; window.el = this; document.head.appendChild(this) } })<\/script><body><x-a x=1><p>y</p></x-a>`);
	const w = iframe.contentWindow, d = iframe.contentDocument;
	assert_equals(w.el.parentNode, d.head, "the custom element stayed where the callback put it");
	assert_equals(tree(d.body), ``, "the custom element was not also inserted into body");
	assert_equals(tree(w.el), `<p>["y"]`, "following content went into the custom element");
	}, "attributeChangedCallback gives the element a parent before it is inserted");

	promise_test(async t => {
	const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement { static get observedAttributes() { return ['x'] } attributeChangedCallback() { if (window.el) return; window.el = this; window.b = document.body; window.b.remove() } })<\/script><body><x-a x=1><p>y</p></x-a>`);
	const w = iframe.contentWindow, d = iframe.contentDocument;
	assert_equals(d.body, null, "the html element no longer has a body child");
	assert_equals(w.b.parentNode, null, "body stayed detached");
	assert_equals(tree(w.b), `<x-a>[<p>["y"]]`, "the element was inserted into the detached body");
	}, "attributeChangedCallback detaches the intended parent before the element is inserted");

	// A shadow root that does not contain the intended parent must not prevent the
	// insertion; this is what an over-broad cycle guard would break.
	promise_test(async t => {
	const iframe = await parseInIframe(t, `<script>customElements.define('x-a', class extends HTMLElement { constructor() { super(); window.el = this; window.root = this.attachShadow({mode: 'open'}); window.root.appendChild(document.createElement('span')) } })<\/script><body><x-a><p>y</p></x-a>`);
	const w = iframe.contentWindow, d = iframe.contentDocument;
	assert_equals(tree(d.body), `<x-a>[<p>["y"]]`, "the element was inserted normally");
	assert_equals(w.root.firstChild.localName, "span", "its shadow root is untouched");
	}, "Custom element constructor attaches an unrelated shadow root");
	</script>