shadow-dom/HTMLSlotElement-interface.html - external/w3c/web-platform-tests - Git at Google

 <!DOCTYPE html>
 <html>
 <head>
 <title>Shadow DOM: HTMLSlotElement interface</title>
 <meta name="author" title="Ryosuke Niwa" href="mailto:rniwa@webkit.org">
 <meta name="assert" content="HTMLSlotElement must exist on window with name attribute and getAssignedNode() method">
 <link rel="help" href="https://w3c.github.io/webcomponents/spec/shadow/#the-slot-element">
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 </head>
 <body>
 <div id="log"></div>
 <script>

 test(function () {
  assert_true('HTMLSlotElement' in window, 'HTMLSlotElement must be defined on window');
  assert_equals(HTMLSlotElement.prototype.__proto__, HTMLElement.prototype, 'HTMLSlotElement should inherit from HTMLElement');
  assert_true(document.createElement('slot') instanceof HTMLSlotElement, 'slot element should be an instance of HTMLSlotElement');
  assert_true(document.createElement('slot') instanceof HTMLElement, 'slot element should be an instance of HTMLElement');
 }, 'HTMLSlotElement must be defined on window');

 test(function () {
  assert_true('name' in HTMLSlotElement.prototype, '"name" attribute must be defined on HTMLSlotElement.prototype');

  var slotElement = document.createElement('slot');
  assert_equals(slotElement.name, '', '"name" attribute must return the empty string when "name" content attribute is not set');

  slotElement.setAttribute('name', 'foo');
  assert_equals(slotElement.name, 'foo', '"name" attribute must return the value of the "name" content attribute');

  slotElement.name = 'bar';
  assert_equals(slotElement.name, 'bar', '"name" attribute must return the assigned value');
  assert_equals(slotElement.getAttribute('name'), 'bar', '"name" attribute must update the "name" content attribute');
 }, '"name" attribute on HTMLSlotElement must reflect "name" attribute');

 function testSlotOutsideShadowTree(options)
 {
  test(function () {
  assert_true('assignedNodes' in HTMLSlotElement.prototype, '"assignedNodes" method must be defined on HTMLSlotElement.prototype');

  var slotElement = document.createElement('slot');
  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() must return an empty array when the slot element is not in any tree');

  document.body.appendChild(slotElement);
  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() must return an empty array when the slot element is in a document tree');

  }, 'assignedNodes(' + (options ? JSON.stringify(options) : '')
  + ') on a HTMLSlotElement must return an empty array when the slot element is not in a tree or in a document tree');
 }

 testSlotOutsideShadowTree(null);
 testSlotOutsideShadowTree({flattened: false});
 testSlotOutsideShadowTree({flattened: true});

 function testSingleLevelOfSlotting(options)
 {
  test(function () {
  assert_true('assignedNodes' in HTMLSlotElement.prototype, '"assignedNodes" method must be defined on HTMLSlotElement.prototype');

  var shadowHost = document.createElement('div');
  var child = document.createElement('p');

  var shadowRoot = shadowHost.attachShadow({mode: 'open'});
  var slotElement = document.createElement('slot');
  shadowRoot.appendChild(slotElement);

  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() must return an empty array when there are no nodes in the shadow tree');

  shadowHost.appendChild(child);
  assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes() on a default slot must return an element without slot element');

  child.setAttribute('slot', 'foo');
  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() on a default slot must not return an element with non-empty slot attribute');

  child.setAttribute('slot', '');
  assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes() on a default slot must return an element with empty slot attribute');

  slotElement.setAttribute('name', 'bar');
  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() on a named slot must not return an element with empty slot attribute');

  slotElement.setAttribute('name', '');
  assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes() on an empty name slot must return an element with empty slot attribute');

  }, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must return the list of assigned nodes when none of the assigned nodes themselves are slots');
 }

 testSingleLevelOfSlotting(null);
 testSingleLevelOfSlotting({flattened: false});
 testSingleLevelOfSlotting({flattened: true});

 function testMutatingSlottedContents(options)
 {
  test(function () {
  var shadowHost = document.createElement('div');
  var p = document.createElement('p');
  var b = document.createElement('b');
  shadowHost.appendChild(p);
  shadowHost.appendChild(b);

  var shadowRoot = shadowHost.attachShadow({mode: 'open'});
  var slotElement = document.createElement('slot');
  shadowRoot.appendChild(slotElement);

  assert_array_equals(slotElement.assignedNodes(options), [p, b], 'assignedNodes must return the distributed nodes');

  slotElement.name = 'foo';
  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes must be empty when there are no matching elements for the slot name');

  b.slot = 'foo';
  assert_array_equals(slotElement.assignedNodes(options), [b], 'assignedNodes must return the nodes with the matching slot name');

  p.slot = 'foo';
  assert_array_equals(slotElement.assignedNodes(options), [p, b], 'assignedNodes must return the nodes with the matching slot name in the tree order');

  slotElement.removeAttribute('name');
  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes must be empty for a default slot when all elements have "slot" attributes specified');

  }, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must update when slot and name attributes are modified');
 }

 testMutatingSlottedContents(null);
 testMutatingSlottedContents({flattened: false});
 testMutatingSlottedContents({flattened: true});

 function testMutatingSlotName(options)
 {
  test(function () {
  var shadowHost = document.createElement('div');
  var child = document.createElement('span');
  shadowHost.appendChild(child);

  var shadowRoot = shadowHost.attachShadow({mode: 'open'});
  var slotElement = document.createElement('slot');
  slotElement.name = 'foo';
  shadowRoot.appendChild(slotElement);

  assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes must be empty when there are no matching elements for the slot name');

  slotElement.removeAttribute('name');
  assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes must be empty when there are no matching elements for the slot name');

  }, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must update when a default slot is introduced dynamically by a slot rename');
 }

 testMutatingSlotName(null);
 testMutatingSlotName({flattened: false});
 testMutatingSlotName({flattened: true});

 function testInsertingAndRemovingSlots(options)
 {
  test(function () {
  var shadowHost = document.createElement('div');
  var p = document.createElement('p');
  var text = document.createTextNode('');
  var comment = document.createComment('');
  var processingInstruction = document.createProcessingInstruction('target', 'data');
  var b = document.createElement('b');
  shadowHost.appendChild(p);
  shadowHost.appendChild(text);
  shadowHost.appendChild(comment);
  shadowHost.appendChild(processingInstruction);
  shadowHost.appendChild(b);

  var shadowRoot = shadowHost.attachShadow({mode: 'open'});

  var firstSlotElement = document.createElement('slot');
  shadowRoot.appendChild(firstSlotElement);

  var secondSlotElement = document.createElement('slot');
  shadowRoot.appendChild(secondSlotElement);

  assert_array_equals(firstSlotElement.assignedNodes(options), [p, text, b],
  'assignedNodes on a default slot must return the elements without slot attributes and text nodes');
  assert_array_equals(secondSlotElement.assignedNodes(options), [],
  'assignedNodes on the second unnamed slot element must return an empty array');

  shadowRoot.removeChild(firstSlotElement);
  assert_array_equals(firstSlotElement.assignedNodes(options), [],
  'assignedNodes on a detached formerly-default slot must return an empty array');
  assert_array_equals(secondSlotElement.assignedNodes(options), [p, text, b],
  'assignedNodes on the second unnamed slot element after removing the first must return the elements without slot attributes and text nodes');

  shadowRoot.removeChild(secondSlotElement);
  shadowRoot.appendChild(secondSlotElement);
  assert_array_equals(firstSlotElement.assignedNodes(options), [],
  'Removing and re-inserting a default slot must not change the result of assignedNodes on a detached slot');
  assert_array_equals(secondSlotElement.assignedNodes(options), [p, text, b],
  'Removing and re-inserting a default slot must not change the result of assignedNodes');

  shadowRoot.insertBefore(firstSlotElement, secondSlotElement);
  assert_array_equals(firstSlotElement.assignedNodes(options), [p, text, b],
  'assignedNodes on a newly inserted unnamed slot element must return the elements without slot attributes and text nodes');
  assert_array_equals(secondSlotElement.assignedNodes(options), [],
  'assignedNodes on formerly-first but now second unnamed slot element must return an empty array');

  }, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must update when slot elements are inserted or removed');
 }

 testInsertingAndRemovingSlots(null);
 testInsertingAndRemovingSlots({flattened: false});
 testInsertingAndRemovingSlots({flattened: true});

 test(function () {
  var outerHost = document.createElement('div');
  var outerChild = document.createElement('span');
  outerHost.appendChild(outerChild);

  var outerShadow = outerHost.attachShadow({mode: 'closed'});
  var innerHost = document.createElement('div');
  var outerSlot = document.createElement('slot');
  var innerChild = document.createElement('b');
  outerShadow.appendChild(innerHost);
  innerHost.appendChild(outerSlot);
  innerHost.appendChild(innerChild);

  var innerShadow = innerHost.attachShadow({mode: 'closed'});
  var innerSlot = document.createElement('slot');
  innerShadow.appendChild(innerSlot);

  assert_array_equals(outerSlot.assignedNodes(), [outerChild], 'assignedNodes() on a default slot must return the assigned nodes');
  assert_array_equals(outerSlot.assignedNodes({flatten: false}), [outerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
  assert_array_equals(outerSlot.assignedNodes({flatten: true}), [outerChild], 'assignedNodes({flatten: true}) on a default slot must return the assigned nodes if they are not themselves slots');

  assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

  outerSlot.name = 'foo';
  assert_array_equals(outerSlot.assignedNodes(), [], 'assignedNodes() on a named slot must return an empty array if there are no matching elements');
  assert_array_equals(outerSlot.assignedNodes({flatten: false}), [], 'assignedNodes({flatten: false}) on a named slot must return an empty array if there are no matching elements');
  assert_array_equals(outerSlot.assignedNodes({flatten: true}), [], 'assignedNodes({flatten: true}) on a named slot must return an empty array if there are no matching elements');

  assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: true}), [innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

  outerChild.slot = 'foo';
  assert_array_equals(outerSlot.assignedNodes(), [outerChild], 'assignedNodes() on a named slot must return matching elements');
  assert_array_equals(outerSlot.assignedNodes({flatten: false}), [outerChild], 'assignedNodes({flatten: false}) on a named slot must return matching elements');
  assert_array_equals(outerSlot.assignedNodes({flatten: true}), [outerChild], 'assignedNodes({flatten: true}) on a named slot must return matching elements');

  assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

  var newInnerSlot = document.createElement('slot');
  innerShadow.insertBefore(newInnerSlot, innerSlot);
  assert_array_equals(newInnerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
  assert_array_equals(newInnerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
  assert_array_equals(newInnerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

  assert_array_equals(innerSlot.assignedNodes(), [], 'assignedNodes() on a nameless slot element which appears after a default slot must return an empty array');
  assert_array_equals(innerSlot.assignedNodes({flatten: false}), [], 'assignedNodes({flatten: false}) on a nameless slot element which appears after a default slot must return an empty array');
  assert_array_equals(innerSlot.assignedNodes({flatten: true}), [], 'assignedNodes({flatten: true}) on a nameless slot element which appears after a default slot must return an empty array');

  innerShadow.removeChild(newInnerSlot);
  assert_array_equals(newInnerSlot.assignedNodes(), [], 'assignedNodes() must return an empty array when the slot element is not in any tree');
  assert_array_equals(newInnerSlot.assignedNodes({flatten: false}), [], 'assignedNodes({flatten: false}) must return an empty array when the slot element is not in any tree');
  assert_array_equals(newInnerSlot.assignedNodes({flatten: true}), [], 'assignedNodes({flatten: true}) must return an empty array when the slot element is not in any tree');

  assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
  assert_array_equals(innerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

 }, 'assignedNodes({flatten: true}) must return the distributed nodes, and assignedNodes() and assignedNodes({flatten: false}) must returned the assigned nodes');

 </script>
 </body>
 </html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>Shadow DOM: HTMLSlotElement interface</title>
	<meta name="author" title="Ryosuke Niwa" href="mailto:rniwa@webkit.org">
	<meta name="assert" content="HTMLSlotElement must exist on window with name attribute and getAssignedNode() method">
	<link rel="help" href="https://w3c.github.io/webcomponents/spec/shadow/#the-slot-element">
	<script src="/resources/testharness.js"></script>
	<script src="/resources/testharnessreport.js"></script>
	</head>
	<body>
	<div id="log"></div>
	<script>

	test(function () {
	assert_true('HTMLSlotElement' in window, 'HTMLSlotElement must be defined on window');
	assert_equals(HTMLSlotElement.prototype.__proto__, HTMLElement.prototype, 'HTMLSlotElement should inherit from HTMLElement');
	assert_true(document.createElement('slot') instanceof HTMLSlotElement, 'slot element should be an instance of HTMLSlotElement');
	assert_true(document.createElement('slot') instanceof HTMLElement, 'slot element should be an instance of HTMLElement');
	}, 'HTMLSlotElement must be defined on window');

	test(function () {
	assert_true('name' in HTMLSlotElement.prototype, '"name" attribute must be defined on HTMLSlotElement.prototype');

	var slotElement = document.createElement('slot');
	assert_equals(slotElement.name, '', '"name" attribute must return the empty string when "name" content attribute is not set');

	slotElement.setAttribute('name', 'foo');
	assert_equals(slotElement.name, 'foo', '"name" attribute must return the value of the "name" content attribute');

	slotElement.name = 'bar';
	assert_equals(slotElement.name, 'bar', '"name" attribute must return the assigned value');
	assert_equals(slotElement.getAttribute('name'), 'bar', '"name" attribute must update the "name" content attribute');
	}, '"name" attribute on HTMLSlotElement must reflect "name" attribute');

	function testSlotOutsideShadowTree(options)
	{
	test(function () {
	assert_true('assignedNodes' in HTMLSlotElement.prototype, '"assignedNodes" method must be defined on HTMLSlotElement.prototype');

	var slotElement = document.createElement('slot');
	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() must return an empty array when the slot element is not in any tree');

	document.body.appendChild(slotElement);
	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() must return an empty array when the slot element is in a document tree');

	}, 'assignedNodes(' + (options ? JSON.stringify(options) : '')
	+ ') on a HTMLSlotElement must return an empty array when the slot element is not in a tree or in a document tree');
	}

	testSlotOutsideShadowTree(null);
	testSlotOutsideShadowTree({flattened: false});
	testSlotOutsideShadowTree({flattened: true});

	function testSingleLevelOfSlotting(options)
	{
	test(function () {
	assert_true('assignedNodes' in HTMLSlotElement.prototype, '"assignedNodes" method must be defined on HTMLSlotElement.prototype');

	var shadowHost = document.createElement('div');
	var child = document.createElement('p');

	var shadowRoot = shadowHost.attachShadow({mode: 'open'});
	var slotElement = document.createElement('slot');
	shadowRoot.appendChild(slotElement);

	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() must return an empty array when there are no nodes in the shadow tree');

	shadowHost.appendChild(child);
	assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes() on a default slot must return an element without slot element');

	child.setAttribute('slot', 'foo');
	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() on a default slot must not return an element with non-empty slot attribute');

	child.setAttribute('slot', '');
	assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes() on a default slot must return an element with empty slot attribute');

	slotElement.setAttribute('name', 'bar');
	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes() on a named slot must not return an element with empty slot attribute');

	slotElement.setAttribute('name', '');
	assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes() on an empty name slot must return an element with empty slot attribute');

	}, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must return the list of assigned nodes when none of the assigned nodes themselves are slots');
	}

	testSingleLevelOfSlotting(null);
	testSingleLevelOfSlotting({flattened: false});
	testSingleLevelOfSlotting({flattened: true});

	function testMutatingSlottedContents(options)
	{
	test(function () {
	var shadowHost = document.createElement('div');
	var p = document.createElement('p');
	var b = document.createElement('b');
	shadowHost.appendChild(p);
	shadowHost.appendChild(b);

	var shadowRoot = shadowHost.attachShadow({mode: 'open'});
	var slotElement = document.createElement('slot');
	shadowRoot.appendChild(slotElement);

	assert_array_equals(slotElement.assignedNodes(options), [p, b], 'assignedNodes must return the distributed nodes');

	slotElement.name = 'foo';
	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes must be empty when there are no matching elements for the slot name');

	b.slot = 'foo';
	assert_array_equals(slotElement.assignedNodes(options), [b], 'assignedNodes must return the nodes with the matching slot name');

	p.slot = 'foo';
	assert_array_equals(slotElement.assignedNodes(options), [p, b], 'assignedNodes must return the nodes with the matching slot name in the tree order');

	slotElement.removeAttribute('name');
	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes must be empty for a default slot when all elements have "slot" attributes specified');

	}, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must update when slot and name attributes are modified');
	}

	testMutatingSlottedContents(null);
	testMutatingSlottedContents({flattened: false});
	testMutatingSlottedContents({flattened: true});

	function testMutatingSlotName(options)
	{
	test(function () {
	var shadowHost = document.createElement('div');
	var child = document.createElement('span');
	shadowHost.appendChild(child);

	var shadowRoot = shadowHost.attachShadow({mode: 'open'});
	var slotElement = document.createElement('slot');
	slotElement.name = 'foo';
	shadowRoot.appendChild(slotElement);

	assert_array_equals(slotElement.assignedNodes(options), [], 'assignedNodes must be empty when there are no matching elements for the slot name');

	slotElement.removeAttribute('name');
	assert_array_equals(slotElement.assignedNodes(options), [child], 'assignedNodes must be empty when there are no matching elements for the slot name');

	}, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must update when a default slot is introduced dynamically by a slot rename');
	}

	testMutatingSlotName(null);
	testMutatingSlotName({flattened: false});
	testMutatingSlotName({flattened: true});

	function testInsertingAndRemovingSlots(options)
	{
	test(function () {
	var shadowHost = document.createElement('div');
	var p = document.createElement('p');
	var text = document.createTextNode('');
	var comment = document.createComment('');
	var processingInstruction = document.createProcessingInstruction('target', 'data');
	var b = document.createElement('b');
	shadowHost.appendChild(p);
	shadowHost.appendChild(text);
	shadowHost.appendChild(comment);
	shadowHost.appendChild(processingInstruction);
	shadowHost.appendChild(b);

	var shadowRoot = shadowHost.attachShadow({mode: 'open'});

	var firstSlotElement = document.createElement('slot');
	shadowRoot.appendChild(firstSlotElement);

	var secondSlotElement = document.createElement('slot');
	shadowRoot.appendChild(secondSlotElement);

	assert_array_equals(firstSlotElement.assignedNodes(options), [p, text, b],
	'assignedNodes on a default slot must return the elements without slot attributes and text nodes');
	assert_array_equals(secondSlotElement.assignedNodes(options), [],
	'assignedNodes on the second unnamed slot element must return an empty array');

	shadowRoot.removeChild(firstSlotElement);
	assert_array_equals(firstSlotElement.assignedNodes(options), [],
	'assignedNodes on a detached formerly-default slot must return an empty array');
	assert_array_equals(secondSlotElement.assignedNodes(options), [p, text, b],
	'assignedNodes on the second unnamed slot element after removing the first must return the elements without slot attributes and text nodes');

	shadowRoot.removeChild(secondSlotElement);
	shadowRoot.appendChild(secondSlotElement);
	assert_array_equals(firstSlotElement.assignedNodes(options), [],
	'Removing and re-inserting a default slot must not change the result of assignedNodes on a detached slot');
	assert_array_equals(secondSlotElement.assignedNodes(options), [p, text, b],
	'Removing and re-inserting a default slot must not change the result of assignedNodes');

	shadowRoot.insertBefore(firstSlotElement, secondSlotElement);
	assert_array_equals(firstSlotElement.assignedNodes(options), [p, text, b],
	'assignedNodes on a newly inserted unnamed slot element must return the elements without slot attributes and text nodes');
	assert_array_equals(secondSlotElement.assignedNodes(options), [],
	'assignedNodes on formerly-first but now second unnamed slot element must return an empty array');

	}, 'assignedNodes(' + (options ? JSON.stringify(options) : '') + ') must update when slot elements are inserted or removed');
	}

	testInsertingAndRemovingSlots(null);
	testInsertingAndRemovingSlots({flattened: false});
	testInsertingAndRemovingSlots({flattened: true});

	test(function () {
	var outerHost = document.createElement('div');
	var outerChild = document.createElement('span');
	outerHost.appendChild(outerChild);

	var outerShadow = outerHost.attachShadow({mode: 'closed'});
	var innerHost = document.createElement('div');
	var outerSlot = document.createElement('slot');
	var innerChild = document.createElement('b');
	outerShadow.appendChild(innerHost);
	innerHost.appendChild(outerSlot);
	innerHost.appendChild(innerChild);

	var innerShadow = innerHost.attachShadow({mode: 'closed'});
	var innerSlot = document.createElement('slot');
	innerShadow.appendChild(innerSlot);

	assert_array_equals(outerSlot.assignedNodes(), [outerChild], 'assignedNodes() on a default slot must return the assigned nodes');
	assert_array_equals(outerSlot.assignedNodes({flatten: false}), [outerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
	assert_array_equals(outerSlot.assignedNodes({flatten: true}), [outerChild], 'assignedNodes({flatten: true}) on a default slot must return the assigned nodes if they are not themselves slots');

	assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

	outerSlot.name = 'foo';
	assert_array_equals(outerSlot.assignedNodes(), [], 'assignedNodes() on a named slot must return an empty array if there are no matching elements');
	assert_array_equals(outerSlot.assignedNodes({flatten: false}), [], 'assignedNodes({flatten: false}) on a named slot must return an empty array if there are no matching elements');
	assert_array_equals(outerSlot.assignedNodes({flatten: true}), [], 'assignedNodes({flatten: true}) on a named slot must return an empty array if there are no matching elements');

	assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: true}), [innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

	outerChild.slot = 'foo';
	assert_array_equals(outerSlot.assignedNodes(), [outerChild], 'assignedNodes() on a named slot must return matching elements');
	assert_array_equals(outerSlot.assignedNodes({flatten: false}), [outerChild], 'assignedNodes({flatten: false}) on a named slot must return matching elements');
	assert_array_equals(outerSlot.assignedNodes({flatten: true}), [outerChild], 'assignedNodes({flatten: true}) on a named slot must return matching elements');

	assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

	var newInnerSlot = document.createElement('slot');
	innerShadow.insertBefore(newInnerSlot, innerSlot);
	assert_array_equals(newInnerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
	assert_array_equals(newInnerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
	assert_array_equals(newInnerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

	assert_array_equals(innerSlot.assignedNodes(), [], 'assignedNodes() on a nameless slot element which appears after a default slot must return an empty array');
	assert_array_equals(innerSlot.assignedNodes({flatten: false}), [], 'assignedNodes({flatten: false}) on a nameless slot element which appears after a default slot must return an empty array');
	assert_array_equals(innerSlot.assignedNodes({flatten: true}), [], 'assignedNodes({flatten: true}) on a nameless slot element which appears after a default slot must return an empty array');

	innerShadow.removeChild(newInnerSlot);
	assert_array_equals(newInnerSlot.assignedNodes(), [], 'assignedNodes() must return an empty array when the slot element is not in any tree');
	assert_array_equals(newInnerSlot.assignedNodes({flatten: false}), [], 'assignedNodes({flatten: false}) must return an empty array when the slot element is not in any tree');
	assert_array_equals(newInnerSlot.assignedNodes({flatten: true}), [], 'assignedNodes({flatten: true}) must return an empty array when the slot element is not in any tree');

	assert_array_equals(innerSlot.assignedNodes(), [outerSlot, innerChild], 'assignedNodes() on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: false}), [outerSlot, innerChild], 'assignedNodes({flatten: false}) on a default slot must return the assigned nodes');
	assert_array_equals(innerSlot.assignedNodes({flatten: true}), [outerChild, innerChild], 'assignedNodes({flatten: true}) on a default slot must return the distributed nodes');

	}, 'assignedNodes({flatten: true}) must return the distributed nodes, and assignedNodes() and assignedNodes({flatten: false}) must returned the assigned nodes');

	</script>
	</body>
	</html>