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+---
+id: mogq50
+name: 'Status text update has `aria-live` property'
+rule_type: atomic
+description: |
+  This rule checks that any status message update has either "polite" or "assertive" `aria-live` property.
+accessibility_requirements:
+  wcag21:4.1.3: # Status Messages (AA)
+    forConformance: true
+    failed: not satisfied
+    passed: further testing needed
+    inapplicable: further testing needed
+  wcag-technique:ARIA19: # Using ARIA role=alert or Live Regions to Identify Errors
+    forConformance: false
+    failed: not satisfied
+    passed: further testing needed
+    inapplicable: further testing needed
+  wcag-technique:ARIA22: # Using role=status to present status messages
+    forConformance: false
+    failed: not satisfied
+    passed: further testing needed
+    inapplicable: further testing needed
+  wcag-technique:ARIA23: # Using role=log to identify sequential information updates
+    forConformance: false
+    failed: not satisfied
+    passed: further testing needed
+    inapplicable: further testing needed
+input_aspects:
+  - DOM Tree
+  - CSS Styling
+  - Accessibility Tree
+acknowledgments:
+  authors:
+    - aron janecki
+    - jean-yves moyen
+---
+
+## Applicability
+
+This rule applies to any [text node][] that is a [descendant][] of the [HTML element][] in the [flat tree][] if the [text node][] is [included in the accessibility tree][] and at least one of the following is true:
+
+- **change**: the [text node][]'s [ancestor][]'s `innerText` property is changing; or
+- **create**: the [text node][]'s [ancestor][] is either [appended](https://dom.spec.whatwg.org/#concept-node-append) or [inserted](https://dom.spec.whatwg.org/#concept-node-insert); or
+- **replaced**: the [text node][]'s [ancestor][] was [replaced](https://dom.spec.whatwg.org/#concept-node-replace).
+
+## Expectation
+
+For each test target at least one of the following is true:
+
+- the test target has an accessible object as an ancestor in the accessibility tree with an implicit or explicit `aria-live` value of "assertive" or "polite"; or
+- there is a text node with an equivalent message that has an accessible object as an ancestor in the accessibility tree with an implicit or explicit `aria-live` value of "assertive" or "polite".
+
+## Assumptions
+
+The text changes meet the definition of [status message][]. If this is not the case, success criterion [4.1.3 Status Messages][success criterion 4.1.3 status messages] may be satisfied even if this rule failed.
+
+This rule assumes that the [explicit role][] of the elements does not need to be appropriate to satisfy success criterion [4.1.3 Status Messages][success criterion 4.1.3 status messages]. For example, using `role="alert"` on elements with score updates may be of concern for success criterion [1.3.1 Info and Relationships][success criterion 1.3.1 info and relationships] because the `role="status"` appears to be more appropriate in such a context.
+
+This rule assumes that the changes happen within a 1 minute time span after the event firing and therefore the comparison between the page before and after the [event](https://dom.spec.whatwg.org/#concept-event) [firing](https://dom.spec.whatwg.org/#concept-event-fire) can be made at any time after that time span elapses. If there are changes after this time span, they may not be detected as [changes in content][event originated change in the content] and the rule may pass but [success criterion 4.1.3 Status Messages][] is not satisfied. The arbitrary 1 minute time span, selected so that testing this rule would not be impractical, is not included in WCAG.
+
+## Accessibility Support
+
+There exists a known combination of operating system and browsers that do not specify the implicit `aria-live` property.
+
+## Background
+
+- [ARIA19: Using ARIA role=alert or Live Regions to Identify Errors](https://www.w3.org/WAI/WCAG21/Techniques/aria/ARIA19.html)
+- [ARIA21: Using role=status to present status messages](https://www.w3.org/WAI/WCAG21/Techniques/aria/ARIA22.html)
+- [ARIA23: Using role=log to identify sequential information updates](https://www.w3.org/WAI/WCAG21/Techniques/aria/ARIA23.html)
+
+## Test Cases
+
+### Passed
+
+#### Passed Example 1
+
+The `p` element that appears after activating submit button with no value for the first name field has `role="alert"`. `role="alert"` has an implicit `aria-live` value of "assertive".
+
+```html
+<body>
+	<label>First name:<input /></label>
+	<input type="button" onclick="checkErrors()" value="Submit" />
+
+	<script>
+		const fNameInput = document.querySelector('label input')
+
+		const checkErrors = () => {
+			if (fNameInput.value === '') {
+				let para = document.createElement('p')
+				para.innerText = 'Error: First name field must not be blank'
+				para.setAttribute('role', 'alert')
+				document.body.prepend(para)
+			}
+		}
+	</script>
+</body>
+```
+
+#### Passed Example 2
+
+This `p` element with `role="status"` has an implicit `aria-live` value of "polite".
+
+```html
+<label>Search for a phrase<input /></label>
+
+<p role="status">Found phrases: 0</p>
+
+<input type="button" onclick="searchPhrase()" value="Search" />
+
+<blockquote cite="https://www.w3.org/WAI/WCAG21/Understanding/status-messages.html">
+	<p id="rich-text">
+		"When appropriate roles or properties are assigned to status messages, the new content is spoken by screen readers
+		in such a way as to assist blind and low vision users. Most sighted users can observe text peripherally added to the
+		viewport. Such content provides additional information without affecting the user's current point of regard. The
+		ability of an assistive technology to announce such new important text content allows more users to benefit from an
+		awareness of the information in an equivalent manner."
+	</p>
+</blockquote>
+
+<script>
+	const searchInput = document.querySelector('label input')
+
+	const statusBar = document.querySelector('p[role="status"]')
+
+	const richText = document.getElementById('rich-text')
+
+	const searchPhrase = () => {
+		if (searchInput.value === '') {
+			statusBar.innerText = 'Found phrases: 0'
+		} else {
+			let regex = new RegExp(searchInput.value, 'g')
+			const match = Array.from(richText.innerText.matchAll(regex))
+
+			match ? (statusBar.innerText = 'Found phrases: ' + match.length) : (statusBar.innerText = 'Found phrases: 0')
+		}
+	}
+</script>
+```
+
+#### Passed Example 3
+
+The `p` element with `role="timer"` that appears after activating the "Download" `button` has an explicit `aria-live` value of "polite". `aria-live="polite"` overwrites the implicit value of "off" for elements with `role="timer"`.
+
+```html
+<body>
+	<input type="button" onclick="launchTimer();" value="Download" />
+
+	<script>
+		const launchTimer = () => {
+			let counter = 10
+
+			if (!document.querySelector('p[role="timer"]')) {
+				let para = document.createElement('p')
+				para.setAttribute('aria-live', 'assertive')
+				para.setAttribute('role', 'timer')
+				document.body.append(para)
+
+				const timer = document.querySelector('p[role="timer"]')
+
+				window.setInterval(() => {
+					if (counter === 10) {
+						timer.innerText = 'Document will download in 10 seconds'
+						counter--
+					} else {
+						counter === -1 ? clearInterval() : (timer.innerText = counter--)
+					}
+				}, 1000)
+			}
+		}
+	</script>
+</body>
+```
+
+#### Passed Example 4
+
+This `div` element with `role="log"` has an implicit `aria-live` value of "polite".
+
+```html
+<body onload="sendNotifications()">
+	<div role="log" aria-labelledby="mainHeading">
+		<h1 id="mainHeading">Notifications panel</h1>
+	</div>
+
+	<script>
+		const log = document.querySelector('div[role="log"]')
+
+		const sendNotifications = () => {
+			let counter = 0
+
+			window.setTimeout(() => {
+				let listObject = {
+					timer: counter,
+					get list() {
+						return document.createElement('ul')
+					},
+					message: ['Notification:', 'Message', 'number '],
+					get listItem() {
+						let item = document.createElement('li')
+						item.innerText = this.message.join(' ')
+						return item
+					},
+				}
+
+				log.append(listObject.list)
+
+				const listNode = document.querySelector('ul')
+
+				listObject.message.push(counter + 1)
+
+				listNode.append(listObject.listItem)
+				++counter
+
+				const intervalID = window.setInterval(() => {
+					console.log(true)
+					if (counter < 10) {
+						let lastItem = listObject.message.length - 1
+						listObject.message[lastItem] = ++counter
+						listNode.insertBefore(listObject.listItem, document.querySelector('ul > li'))
+					} else {
+						clearInterval(intervalID)
+					}
+				}, 3000)
+			}, 5000)
+		}
+	</script>
+</body>
+```
+
+#### Passed Example 5
+
+This `div` element with `role="marquee"` has an implicit `aria-live` value of "off". Pressing the Activate Updates control gives the element the explicit value of "polite".
+
+```html
+<html>
+	<style>
+		.notInPage {
+			position: absolute;
+			left: -9999px;
+			top: -9999px;
+		}
+	</style>
+	<body>
+		<h1 id="mainHeading">Stock tickers website</h1>
+
+		<p>Press Activate Updates to receive live updates of stock values</p>
+		<button onclick="turnOnUpdates()">Activate updates</button>
+		<button onclick="turnOffUpdates()">Turn off updates</button>
+
+		<div role="marquee" aria-labelledby="mainHeading">
+			<table>
+				<thead>
+					<tr>
+						<th scope="col">Company symbol</th>
+						<th scope="col">Last price</th>
+					</tr>
+				</thead>
+				<tbody>
+					<tr>
+						<th scope="row">Comp1</th>
+						<td>0.675</td>
+					</tr>
+					<tr>
+						<th scope="row">Comp2</th>
+						<td>0.543</td>
+					</tr>
+				</tbody>
+			</table>
+		</div>
+
+		<script>
+			const marquee = document.querySelector('div[role="marquee"]')
+			const stockValues = document.querySelectorAll('tr > td')
+
+			const setUpdates = () => {
+				stockValues.forEach((data, index) => {
+					data.innerText = Math.random().toFixed(3)
+					let para = document.createElement('p')
+					para.setAttribute('id', index)
+					para.innerText = 'Company ' + (index + 1) + ' ' + data.innerText
+					para.classList.add('notInPage')
+					marquee.appendChild(para)
+					window.setTimeout(() => {
+						document.getElementById(index).remove()
+					}, 8000)
+				})
+			}
+
+			let intervalID
+
+			const turnOnUpdates = () => {
+				if (!marquee.getAttribute('aria-live')) {
+					intervalID = window.setInterval(setUpdates, 10000)
+					stockValues.forEach(data => {
+						data.setAttribute('aria-live', 'off')
+					})
+					marquee.setAttribute('aria-live', 'polite')
+					intervalID
+				}
+			}
+
+			const turnOffUpdates = () => {
+				if (marquee.getAttribute('aria-live')) {
+					window.clearInterval(intervalID)
+					stockValues.forEach(data => {
+						data.removeAttribute('aria-live', 'off')
+					})
+					marquee.removeAttribute('aria-live')
+				}
+			}
+		</script>
+	</body>
+</html>
+```
+
+#### Passed Example 6
+
+This `div` element has explicit `aria-live` value of "assertive".
+
+```html
+<button onclick="download()">Download file 1</button>
+<div aria-live="assertive"></div>
+
+<script>
+	const div = document.querySelector('div[aria-live="assertive"]')
+
+	const update = () => {
+		let para = document.createElement('p')
+		para.innerText = 'Downloading'
+		div.appendChild(para)
+		let counter = 0
+		const intervalID = window.setInterval(() => {
+			console.log(true)
+			if (counter < 3) {
+				window.setTimeout(() => {
+					div.firstElementChild.innerText += '.'
+					counter++
+				})
+			} else {
+				div.firstElementChild.innerText = 'Download completed'
+				clearInterval(intervalID)
+			}
+		}, 1000)
+	}
+
+	const download = () => {
+		if (div.children.length > 0) {
+			for (element of div.children) {
+				element.remove()
+			}
+			update()
+		} else {
+			update()
+		}
+	}
+</script>
+```
+
+### Failed
+
+#### Failed Example 1
+
+The `p` element that appears after activating submit button with no value for the first name field does not have implicit or explicit `aria-live` value of "polite" or "assertive". `role="alert"` is not a valid ARIA attribute.
+
+```html
+<label>First name:<input /></label>
+<input type="button" onclick="checkErrors()" value="Submit" />
+
+<script>
+	const fNameInput = document.querySelector('label input')
+
+	const checkErrors = () => {
+		if (fNameInput.value === '') {
+			let para = document.createElement('p')
+			para.innerText = 'Error: First name field must not be blank'
+			para.setAttribute('role', 'alerts')
+			document.body.prepend(para)
+		}
+	}
+</script>
+```
+
+#### Failed Example 2
+
+This `p` element, that changes its value in response to a search query, does not have an implicit or explicit `aria-live` value of "polite" or "assertive".
+
+```html
+<label>Search for a phrase<input /></label>
+<input type="button" onclick="searchPhrase()" value="Search" />
+
+<p>Found phrases: 0</p>
+
+<blockquote cite="https://www.w3.org/WAI/WCAG21/Understanding/status-messages.html">
+	<p id="rich-text">
+		"When appropriate roles or properties are assigned to status messages, the new content is spoken by screen readers
+		in such a way as to assist blind and low vision users. Most sighted users can observe text peripherally added to the
+		viewport. Such content provides additional information without affecting the user's current point of regard. The
+		ability of an assistive technology to announce such new important text content allows more users to benefit from an
+		awareness of the information in an equivalent manner."
+	</p>
+</blockquote>
+
+<script>
+	const searchInput = document.querySelector('label input')
+
+	const statusBar = document.querySelector('p')
+
+	const richText = document.getElementById('rich-text')
+
+	const searchPhrase = () => {
+		if (searchInput.value === '') {
+			statusBar.innerText = 'Found phrases: 0'
+		} else {
+			let regex = new RegExp(searchInput.value, 'g')
+			const match = Array.from(richText.innerText.matchAll(regex))
+
+			match ? (statusBar.innerText = 'Found phrases: ' + match.length) : (statusBar.innerText = 'Found phrases: 0')
+		}
+	}
+</script>
+```
+
+#### Failed Example 3
+
+The `p` element with `role="timer"` that appears after activating the "Download" `button` has an implicit `aria-live` value of "off". The `aria-live="politeness"` is not a valid ARIA attribute which means that `aria-live` value of the test target defaults to "off".
+
+```html
+<input type="button" onclick="launchTimer();" value="Download" />
+
+<script>
+	const launchTimer = () => {
+		let counter = 10
+
+		if (!document.querySelector('p[role="timer"]')) {
+			let para = document.createElement('p')
+			para.setAttribute('aria-live', 'politeness')
+			para.setAttribute('role', 'timer')
+			document.body.append(para)
+
+			const timer = document.querySelector('p[role="timer"]')
+
+			window.setInterval(() => {
+				if (counter === 10) {
+					timer.innerText = 'Document will download in 10 seconds'
+					counter--
+				} else {
+					counter === -1 ? clearInterval() : (timer.innerText = counter--)
+				}
+			}, 1000)
+		}
+	}
+</script>
+```
+
+#### Failed Example 4
+
+This `div` element does not have an implicit or explicit `aria-live` value of "polite" or "assertive".
+
+```html
+<button onclick="download()">Download file 1</button>
+<div aria-live="assertive"></div>
+
+<script>
+	const div = document.querySelector('div[aria-live="assertive"]')
+
+	const update = () => {
+		let para = document.createElement('p')
+		para.innerText = 'Downloading'
+		div.appendChild(para)
+		let counter = 0
+		const intervalID = window.setInterval(() => {
+			console.log(true)
+			if (counter < 3) {
+				window.setTimeout(() => {
+					div.firstElementChild.innerText += '.'
+					counter++
+				})
+			} else {
+				div.firstElementChild.innerText = 'Download completed'
+				clearInterval(intervalID)
+			}
+		}, 1000)
+	}
+
+	const download = () => {
+		if (div.children.length > 0) {
+			for (element of div.children) {
+				element.remove()
+			}
+			update()
+		} else {
+			update()
+		}
+	}
+</script>
+```
+
+### Inapplicable
+
+#### Inapplicable Example 1
+
+This `p` element is not an [event originated change in the content][].
+
+```html
+<p>This is static text</p>
+```
+
+#### Inapplicable Example 2
+
+This `p` element is not included in the accessibility tree through the `display: none` property.
+
+```html
+<p style="display:none;" role="status">10 results out of 20</p>
+```
+
+[ancestor]: https://dom.spec.whatwg.org/#concept-tree-ancestor 'Definition of ancestor'
+[descendant]: https://dom.spec.whatwg.org/#concept-tree-descendant
+[event originated change in the content]: https://act-rules.github.io/glossary/#changes-in-content 'Definition of changes in content'
+[explicit role]: https://act-rules.github.io/glossary/#explicit-role 'Definition of explicit semantic role'
+[flat tree]: https://drafts.csswg.org/css-scoping/#flat-tree 'Definition of flat tree'
+[html element]: https://html.spec.whatwg.org/multipage/dom.html#htmlelement
+[included in the accessibility tree]: #included-in-the-accessibility-tree 'Definition of included in the accessibility tree'
+[status message]: https://www.w3.org/TR/WCAG21/#dfn-status-messages
+[success criterion 1.3.1 info and relationships]: https://www.w3.org/TR/WCAG21/#info-and-relationships
+[success criterion 4.1.3 status messages]: https://www.w3.org/TR/WCAG21/#status-messages
+[text node]: https://dom.spec.whatwg.org/#text