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Test Rule: Link has non-empty accessible name

Description

This rule checks that each link has a non-empty accessible name.

Applicability

This rule applies to any HTML element that is a semantic link included in the accessibility tree.

Expectation

Each target element has an accessible name that is not empty ("").

Assumptions

The rule assumes that all links are user interface components as defined by WCAG 2. When the link role is used on elements that do not behave as links, failing this rule might not mean that the success criteria are failed.

Accessibility Support

Background

Bibliography

Accessibility Requirements Mapping

Input Aspects

The following aspects are required in using this rule.

Test Cases

Passed

Passed Example 1

This a element has an accessible name from its content.

<a href="https://www.w3.org/WAI"> Web Accessibility Initiative (WAI) </a>

Passed Example 2

This div element has an explicit semantic role of link and an accessible name from its content.

<div role="link" onclick="openLink(event)" onkeyup="openLink(event)" tabindex="0">
	Web Accessibility Initiative (WAI)
</div>
<script>
	function openLink(event) {
		if (event.type === 'click' || ['Enter', ' '].includes(event.key)) {
			window.location.href = 'https://www.w3.org/WAI/'
		}
	}
</script>

Passed Example 3

This button element has an explicit semantic role of link and an accessible name from its content.

<button role="link" onclick="window.location.href='https://www.w3.org/WAI/'">Click me for WAI!</button>

Passed Example 4

This a element has an accessible name via aria-label

<a href="https://www.w3.org/WAI"
	><img src="/test-assets/shared/w3c-logo.png" aria-label="Web Accessibility Initiative"
/></a>

Passed Example 5

This a element has an accessible name via title.

<a href="https://www.w3.org/WAI" title="Web Accessibility Initiative"
	><img src="/test-assets/shared/w3c-logo.png" alt=""
/></a>

Passed Example 6

This a element has an accessible name from its content via the title on the img element.

<a href="https://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" title="Web Accessibility Initiative"/></a>

Passed Example 7

This a element has an accessible name from its content.

<a href="https://www.w3.org/WAI"
	><img src="/test-assets/shared/w3c-logo.png" alt="" />Web Accessibility Initiative (WAI)</a
>

Passed Example 8

This a element has an accessible name from its content via aria-labelledby on the img element.

<a href="https://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" aria-labelledby="id1"/></a>
<div id="id1">Web Accessibility Initiative (WAI)</div>

Passed Example 9

This a element placed off screen has an accessible name from its content.

<html>
	<style>
		.offScreenLink {
			position: absolute;
			left: -9999px;
			top: -9999px;
		}
	</style>
	<body>
		<a class="offScreenLink" href="https://www.w3.org/WAI">Web Accessibility Initiative (WAI)</a>
	</body>
</html>

Passed Example 10

This area element has a semantic role of link and an accessible name via alt.

<img src="/test-assets/c487ae/planets.jpg" width="145" height="126" alt="Planets" usemap="#planetmap" />

<map name="planetmap">
	<area shape="rect" coords="0,0,30,100" href="sun.htm" alt="Sun" />
</map>

Failed

Failed Example 1

This a element has an empty accessible name.

<a href="http://www.w3.org/WAI"></a>

Failed Example 2

This a element with an image has an empty accessible name. The image is decorative and is marked as such with an empty alt attribute value.

<a href="https://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" alt=""/></a>

Failed Example 3

This a element with an image has an empty accessible name. The image is decorative because it has a role attribute value of presentation.

<a href="http://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" role="presentation"/></a>

Failed Example 4

This a element with an image has an empty accessible name. The image is decorative because it has a role attribute value of none.

<a href="http://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" role="none"/></a>

Failed Example 5

This a element with an img with an empty title has an empty accessible name.

<a href="https://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" title=""/></a>

Failed Example 6

This a element with an img with an aria-labelledby has an empty accessible name.

<a href="https://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" aria-labelledby="id1"/></a>
<div id="id1"></div>

Failed Example 7

This a element with an img with an aria-labelledby referencing a non-existing id has an empty accessible name.

<a href="https://www.w3.org/WAI"><img src="/test-assets/shared/w3c-logo.png" aria-labelledby="id1"/></a>

Failed Example 8

This a element placed off screen has an empty accessible name.

<a href="https://www.w3.org/WAI" style="left: -9999px; position: absolute;">
	<img src="/test-assets/shared/w3c-logo.png" />
</a>

Failed Example 9

This area element has a semantic role of link and an empty accessible name.

<img src="/test-assets/c487ae/planets.jpg" width="145" height="126" alt="Planets" usemap="#planetmap" />

<map name="planetmap">
	<area shape="rect" coords="0,0,82,126" href="sun.htm" />
</map>

Failed Example 10

This a element has an explicit role of none. However, it is focusable (by default). Thus it has a semantic role of link due to Presentational Roles Conflict Resolution. It has an empty accessible name.

<a href="https://www.w3.org/WAI" role="none"> </a>

Inapplicable

Inapplicable Example 1

This a element does not have a semantic role of link because it has been changed to button.

<a href="https://www.w3.org/WAI" role="button">
	Web Accessibility Initiative (WAI)
</a>

Inapplicable Example 2

This a element is not included in the accessibility tree due to display: none.

<a href="https://www.w3.org/WAI" style="display: none;"><img src="/test-assets/shared/w3c-logo.png"/></a>

Inapplicable Example 3

This a element is not included in the accessibility tree due to visibility: hidden.

<a href="https://www.w3.org/WAI" style="visibility: hidden;">Some text</a>

Inapplicable Example 4

This a element is not included in the accessibility tree due to aria-hidden="true".

<a aria-hidden="true" href="https://www.w3.org/WAI">
	Web Accessibility Initiative (WAI)
</a>

Inapplicable Example 5

This area element does not have the role of link because it does not have an href attribute.

<area shape="rect" coords="0,0,82,126" />

Inapplicable Example 6

This a element does not have the role of link because it does not have an href attribute.

<a />

Glossary

Accessible Name

The accessible name is the programmatically determined name of a user interface element that is included in the accessibility tree.

The accessible name is calculated using the accessible name and description computation.

For native markup languages, such as HTML and SVG, additional information on how to calculate the accessible name can be found in HTML Accessibility API Mappings 1.0, Accessible Name and Description Computation (working draft) and SVG Accessibility API Mappings, Name and Description (working draft).

For more details, see examples of accessible name.

Note: As per the accessible name and description computation, each element always has an accessible name. When no accessible name is provided, the element will nonetheless be assigned an empty ("") one.

Note: As per the accessible name and description computation, accessible names are flat string trimmed of leading and trailing whitespace. Notably, it is not possible for a non-empty accessible name to be composed only of whitespace since these must be trimmed.

Attribute value

The attribute value of a content attribute set on an HTML element is the value that the attribute gets after being parsed and computed according to specifications. It may differ from the value that is actually written in the HTML code due to trimming whitespace or non-digits characters, default values, or case-insensitivity.

Some notable case of attribute value, among others:

This list is not exhaustive, and only serves as an illustration for some of the most common cases.

The attribute value of an IDL attribute is the value returned on getting it. Note that when an IDL attribute reflects a content attribute, they have the same attribute value.

Explicit Semantic Role

The explicit semantic role of an element is determined by its role attribute (if any).

The role attribute takes a list of tokens. The explicit semantic role is the first valid role in this list. The valid roles are all non-abstract roles from WAI-ARIA Specifications. If the element has no role attribute, or if it has one with no valid role, then this element has no explicit semantic role.

Other roles may be added as they become available. Not all roles will be supported in all assistive technologies. Testers are encouraged to adjust which roles are allowed according to the accessibility support base line. For the purposes of executing test cases in all rules, it should be assumed that all roles are supported by assistive technologies so that none of the roles fail due to lack of accessibility support.

Focusable

Elements that can become the target of keyboard input as described in the HTML specification of focusable and can be focused.

Implicit Semantic Role

The implicit semantic role of an element is a pre-defined value given by the host language which depends on the element and its ancestors.

Implicit roles for HTML and SVG, are documented in the HTML accessibility API mappings (working draft) and the SVG accessibility API mappings (working draft).

Included in the accessibility tree

Elements included in the accessibility tree of platform specific accessibility APIs are exposed to assistive technologies. This allows users of assistive technology to access the elements in a way that meets the requirements of the individual user.

The general rules for when elements are included in the accessibility tree are defined in the core accessibility API mappings. For native markup languages, such as HTML and SVG, additional rules for when elements are included in the accessibility tree can be found in the HTML accessibility API mappings (working draft) and the SVG accessibility API mappings (working draft).

For more details, see examples of included in the accessibility tree.

Programmatically hidden elements are removed from the accessibility tree. However, some browsers will leave focusable elements with an aria-hidden attribute set to true in the accessibility tree. Because they are hidden, these elements are considered not included in the accessibility tree. This may cause confusion for users of assistive technologies because they may still be able to interact with these focusable elements using sequential keyboard navigation, even though the element should not be included in the accessibility tree.

Marked as decorative

An element is marked as decorative if one or more of the following conditions is true:

Elements are marked as decorative as a way to convey the intention of the author that they are pure decoration. It is different from the element actually being pure decoration as authors may make mistakes. It is different from the element being effectively ignored by assistive technologies as rules such as presentational roles conflict resolution may overwrite this intention.

Elements can also be ignored by assistive technologies if they are programmatically hidden. This is different from marking the element as decorative and does not convey the same intention. Notably, being programmatically hidden may change as users interact with the page (showing and hiding elements) while being marked as decorative should stay the same through all states of the page.

Namespaced Element

An element with a specific namespaceURI value from HTML namespaces. For example an “SVG element” is any element with the “SVG namespace”, which is http://www.w3.org/2000/svg.

Namespaced elements are not limited to elements described in a specification. They also include custom elements. Elements such as a and title have a different namespace depending on where they are used. For example a title in an HTML page usually has the HTML namespace. When used in an svg element, a title element has the SVG namespace instead.

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:

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.

Programmatically Hidden

An HTML element is programmatically hidden if either it has a computed CSS property visibility whose value is not visible; or at least one of the following is true for any of its inclusive ancestors in the flat tree:

Note: Contrarily to the other conditions, the visibility CSS property may be reverted by descendants.

Semantic Role

The semantic role of an element is determined by the first of these cases that applies:

  1. Conflict If the element is marked as decorative, but the element is included in the accessibility tree; or would be included in the accessibility tree when it is not programmatically hidden, then its semantic role is its implicit role.
  2. Explicit If the element has an explicit role, then its semantic role is its explicit role.
  3. Implicit The semantic role of the element is its implicit role.

This definition can be used in expressions such as “semantic button” meaning any element with a semantic role of button.

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.

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 Consistency Complete Report
Alfa Consistent No View Report
Axe-core Consistent Yes View Report
QualWeb Consistent Yes View Report
SortSite Consistent No View Report

Changelog

This is the first version of this ACT rule.

Back to Top

This is an unpublished draft preview that might include content that is not yet approved. The published website is at w3.org/WAI/.