Audit label-content-name-mismatch
Ensure that elements labelled through their content must have their visible text as part of their accessible name
Impact:
WCAG-Konformität:
- AWCAG 2.5.3
Issue type:
failureVisible label is part of accessible name
This rule checks that interactive elements labeled through content have their visible label as part of their accessible name.
Applicability
This rule applies to any element for which all the following is true:
- The element has a semantic role that is a widget that supports name from content; and
- The element has visible text content; and
- The element has an
aria-label
oraria-labelledby
attribute.
Expectation
For each target element, all text nodes in the visible text content match characters and are contained within the accessible name of this target element, except for characters in the text nodes used to express non-text content. Leading and trailing whitespace and difference in case sensitivity should be ignored.
Background
This rule applies to elements with a widget role that support name from content. This includes the following: button
, checkbox
, gridcell
, link
, menuitem
, menuitemcheckbox
, menuitemradio
, option
, radio
, searchbox
, switch
, tab
, treeitem
.
The understanding document of 2.5.3 Label in Name use the term "symbolic text characters" to refer to a type of non-text content that uses text characters as symbols, such as using "x" to mean "close". This rule considers them as "characters expressing non-text content". Unicode emojis are another example of characters expressing non-text content, although these are not "symbolic text characters".
Assumptions
This rule assumes that all resources needed for rendering the page are properly loaded. Checking if resources are missing is out of the scope of rules. Missing resources may be rendered as text (for example, missing img
are rendered as their alt
attribute).
Accessibility Support
Implementation of Presentational Roles Conflict Resolution varies from one browser or assistive technology to another. Depending on this, some elements can have one of the applicable semantic roles and fail this rule with some technology but users of other technologies would not experience any accessibility issue.
Bibliography
- Understanding Success Criterion 2.5.3: Label in Name
- G208: Including the text of the visible label as part of the accessible name
Test Cases
Passed
Passed Example 1
This link has visible text that matches the accessible name.
<a href="https://act-rules.github.io/" aria-label="ACT rules">ACT rules</a>
Passed Example 2
This link has visible text that, ignoring trailing whitespace, matches the accessible name.
<a href="https://act-rules.github.io/" aria-label=" ACT rules ">ACT rules</a>
Passed Example 3
This link has visible text that, ignoring case, matches the accessible name.
<a href="https://act-rules.github.io/" aria-label="act rules">ACT rules</a>
Passed Example 4
This button has visible text that is contained within the accessible name.
<button aria-label="Next Page in the list">Next Page</button>
Passed Example 5
This button has visible text that does not need to be contained within the accessible name, because the "x" text node is non-text content. Note: this would need to meet SC 1.1.1 Non text content.
<button aria-label="anything">X</button>
Passed Example 6
This button
element has the text "search" rendered as an magnifying glass icon by the font. Because the text is rendered as non-text content, the text does not need to be contained within the accessible name.
<link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet" />
<style>
button {
font-family: 'Material Icons';
}
</style>
<button aria-label="Find">search</button>
Failed
Failed Example 1
This link has visible text that is different from the accessible name.
<a href="https://act-rules.github.io/" aria-label="WCAG">ACT rules</a>
Failed Example 2
This button has visible text that is only partially contained within the accessible name.
<button aria-label="the full">The full label</button>
Failed Example 3
This link has visible text with mathematical symbols, that does not match the accessible name because the mathematical symbols were written out in the accessible name. This is explicitly mentioned in WCAG.
<a href="/" aria-label="Proof of two multiplied by two is four">Proof of 2×2=4</a>
Failed Example 4
This link has visible text does not match the accessible name because there is a hyphen in the accessible name.
<a href="#" aria-label="non-standard">nonstandard</a>
Failed Example 5
This link has visible text does not match the accessible name because there are extra spaces in the accessible name.
<a aria-label="1 2 3. 4 5 6. 7 8 9 0" href="tel:1234567890">123.456.7890</a>
Inapplicable
Inapplicable Example 1
This nav
is not a widget, so the visible text does not need to match the accessible name.
<nav aria-label="main nav">W3C navigation</nav>
Inapplicable Example 2
This email text field does not need to have its visible text match the accessible name. The content of a textfield shows its value instead of its label; it does not support name from content. The label is usually adjacent to the textfield instead.
<div>E-mail</div>
<input type="email" aria-label="E-mail" value="Contact" />
Inapplicable Example 3
This div
element does not have a widget role, so the visible text does not need to match the accessible name.
<div role="tooltip" aria-label="OK">Next</div>
Inapplicable Example 4
This link has no visible text content.
<a href="https://w3.org" aria-label="W3C homepage">
<img src="/test-assets/shared/w3c-logo.png" alt="w3c logo" />
</a>
Autoren: Anne Thyme Nørregaard, Bryn Anderson, Jey Nandakumar
Finanzierung: WAI-Tools