Rule 1.1.3
Summary
This test consists in checking whether each <input>
tag with a type="image"
attribute, carrying information, owns a
textual alternative.
Business description
Criterion
Test
Description
Chaque bouton de type
image
(balise<input>
avec l’attributtype="image"
) a-t-il une alternative textuelle ?
Level
A
Technical description
Scope
Page
Decision level
Decidable with marker
Algorithm
Selection
Set1
All the <input>
tags with a type="image"
attribute, not within a link and not identified as captcha (see Notes about
captcha detection)
Set2
All the elements of Set1 identified as informative image by marker usage (see Notes for details about detection through marker)
Set3
All the elements of Set1 identified neither as informative image, nor as decorative image by marker usage (see Notes for details about detection through marker)
Process
Test1
For each element of Set2, check whether the tag owns a textual alternative (see Notes for details about textual alternative detection).
For each occurrence of false-result of Test1, raise a MessageA.
Test2
For each element of Set3, check whether the tag owns a textual alternative (see Notes for details about textual alternative detection).
For each occurrence of true-result of Test2, raise a MessageB.
For each occurrence of false-result of Test2, raise a MessageC.
Messages
MessageA
- code : AltMissing
- status: Failed
- parameter :
"alt"
attribute,"title"
attribute,"aria-label"
attribute,"computed accessible name"
,"src"
attribute - present in source : yes
MessageB
- code : CheckNatureOfElementWithTextualAlternative
- status: Pre-Qualified
- parameter :
"alt"
attribute,"title"
attribute,"aria-label"
attribute,"computed accessible name"
,"src"
attribute - present in source : yes
MessageC
- code : CheckNatureOfElementWithoutTextualAlternative
- status: Pre-Qualified
- parameter :
"alt"
attribute,"title"
attribute,"aria-label"
attribute,"computed accessible name"
,"src"
attribute - present in source : yes
Analysis
Not Applicable
The page has no <input>
tag with a type="image"
attribute (Set1 is empty)
Passed
All <input>
tags with a type="image"
attribute are identified as informative, and have a textual alternative
(Test1 returns true for all the elements of Set2, and Set3 is empty)
Failed
At least one <input>
tag with a type="image"
attribute, identified as informative, has no textual alternative
(Test1 returns false for at least one element)
Pre-qualified
In all other cases
Notes
Textual alternative detection
The textual alternative can be set by the presence of any the following elements :
- Text associated via the
aria-labelledby
WAI-ARIA attribute - Presence of an
aria-label
WAI-ARIA attribute - Presence of an
alt
attribute - Presence of a
title
attribute
That order has to be respected to compute the textual alternative.
For instance, if an aria-label
WAI-ARIA attribute and an alt
attribute are both present, the content of the
aria-label
WAI-ARIA attribute is considered as the textual alternative.
Markers
Informative images markers are set through the INFORMATIVE_IMAGE_MARKER parameter.
Decorative images markers are set through the DECORATIVE_IMAGE_MARKER parameter.
The value(s) passed as marker(s) will be checked against the following attributes:
class
id
role
Captcha detection
An element is identified as a CAPTCHA when the “captcha” occurrence is found :
- on one attribute of the element
- or within the text of the element
- or on one attribute of one parent of the element
- or within the text of one parent of the element
- or on one attribute of a sibling of the element
- or within the text of a sibling of the element