Proposed ARIA attribute is defined in WAI-ARIA

Description

This rule checks that each aria- attribute specified is defined in ARIA 1.2.

Applicability

This rule applies to any attribute that starts with aria-.

Expectation

Each target attribute is defined in WAI-ARIA Specifications.

Assumptions

There are no assumptions.

Accessibility Support

There are no accessibility support issues known.

Background

The presence of unknown ARIA attributes is often the result of a typo or other developer error. These attributes are ignored by browsers and other assistive technologies. This often means that a state or property which should exist is missing. This can cause issues under success criterion 1.3.1 Info and Relationships or 4.1.2 Name, Rule Value.

Bibliography

Accessibility Requirements Mapping

1.3.1 Info and Relationships (Level A)
- Learn more about 1.3.1 Info and Relationships
- Required for conformance to WCAG 2.0 and later on level A and higher.
- Outcome mapping:
  - Any failed outcomes: success criterion is not satisfied
  - All passed outcomes: success criterion
  - An inapplicable outcome: success criterion
4.1.2 Name, Role, Value (Level A)
- Learn more about 4.1.2 Name, Role, Value
- Required for conformance to WCAG 2.0 and later on level A and higher.
- Outcome mapping:
  - Any failed outcomes: success criterion is not satisfied
  - All passed outcomes: success criterion
  - An inapplicable outcome: success criterion

Input Aspects

The following aspects are required in using this rule.

DOM Tree

Test Cases

Passed

Passed Example 1

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This article element has an aria-atomic attribute which is defined in WAI-ARIA Specifications.

<article aria-atomic="true">This is a description of something cool...</article>

Passed Example 2

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This div element with a role of dialog has an aria-modal attribute which is defined in WAI-ARIA Specifications.

<div role="dialog" aria-modal="true">Contains modal content...</div>

Passed Example 3

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This div element with a role of textbox has multiple aria- attributes which are defined in WAI-ARIA Specifications.

<div
	role="textbox"
	contenteditable="true"
	aria-multiline="true"
	aria-label="Enter your hobbies"
	aria-required="true"
></div>

Passed Example 4

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This input element with a role of spinbutton has multiple aria- attributes specified which are all defined in WAI-ARIA Specifications.

<label for="spinbutton">Enter a number between 0 and 100:</label>
<input
	id="spinbutton"
	role="spinbutton"
	aria-valuemax="100"
	aria-valuemin="0"
	aria-valuenow="25"
	type="number"
	value="25"
/>

Failed

Failed Example 1

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This div element with a role of checkbox has an aria-not-checked attribute which is not defined in WAI-ARIA Specifications.

<div role="checkbox" aria-not-checked="true">All conditions are met</div>

Failed Example 2

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This div element with a role of searchbox has an aria-labelled attribute (instead of aria-labelledby) which is not defined in WAI-ARIA Specifications.

<span id="label">Birthday:</span>
<div contenteditable role="searchbox" aria-labelled="label" aria-placeholder="MM-DD-YYYY">
	01-01-2019
</div>

Inapplicable

Inapplicable Example 1

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This canvas element does not have an aria- attribute specified.

<canvas> </canvas>

Glossary

Outcome

An outcome is a conclusion that comes from evaluating an ACT Rule on a test subject or one of its constituent test target. An outcome can be one of the three following types:

Inapplicable: No part of the test subject matches the applicability
Passed: A test target meets all expectations
Failed: A test target does not meet all expectations

Note: A rule has one passed or failed outcome for every test target. When there are no test targets the rule has one inapplicable outcome. This means that each test subject will have one or more outcomes.

Note: Implementations using the EARL10-Schema can express the outcome with the outcome property. In addition to passed, failed and inapplicable, EARL 1.0 also defined an incomplete outcome. While this cannot be the outcome of an ACT Rule when applied in its entirety, it often happens that rules are only partially evaluated. For example, when applicability was automated, but the expectations have to be evaluated manually. Such “interim” results can be expressed with the incomplete outcome.

WAI-ARIA specifications

The WAI ARIA Specifications group both the WAI ARIA W3C Recommendation and ARIA modules, namely:

Note: depending on the type of content being evaluated, part of the specifications might be irrelevant and should be ignored.

Rule Versions

This is the first version of this ACT rule.

Implementations

This section is not part of the official rule. It is populated dynamically and not accounted for in the change history or the last modified date.

Implementation	Type	Consistency
Alfa 0.56.0	Automated tool	Partial
Axe DevTools Pro 4.37.1	Semi-automated tool	Consistent
Axe-core 4.6.0	Automated tool	Consistent
Equal Access Accessibility Checker 3.1.42-rc.0	Automated tool	Consistent
QualWeb 3.0.0	Automated tool	Consistent
SortSite 6.45	Automated tool	Partial
ember-template-lint 4.16.1	Linter	Partial