Asqatasun v4 - Summary

Asqatasun v4 - AccessiWeb 2.2 - Rule 6.3.2

Summary

This test consists in checking whether the text of an image link is enough explicit to understand the purpose and the target out of its context.

Business description

Criterion : 6.3

Test : 6.3.2

Test description :

Is each text for an image link (content of the alt attribute or content between <object> and </object>) explicit out of context (except in special cases)?

Level : Gold

Technical description

Scope : page

Decision level : semidecidable

Algorithm

Selection

Set1 :

All the <a> tags with a href attribute, with children (a[href]:has(\*) )

Set2 :

All the elements of Set1 without own text and with only one child of type img or object (img , object[type\^=image], object[data\^=data:image], object[data$=png], object[data$=jpeg], object[data$=jpg],object[data$=bmp], object[data$=gif]) (assuming the definition of an image link in AccessiWeb 2.2)

Set3 :

All the elements of Set2 with a child tag with a not empty alt attribute (assuming the definition of a link context in AccessiWeb 2.2)

Process

Test1

For each element of Set2, we check whether the link content (content of the alt attribute of the child tag) doesn't belong to the text link blacklist.

For each element returning false in Test1, raise a MessageA, raise a MessageB instead

Test2

For each element of Set2, we check whether the link content (content of the alt attribute of the child tag) doesn't only contain non alphanumeric characters

For each element returning false in Test2, raise a MessageA, raise a MessageB instead

MessageA : Unexplicit Link
MessageB : Check link without context pertinence

Analysis

NA :

Set1 is empty (the page has no image links)

Failed :

Test1 OR Test2 returns false for at least one element (At least one element of the Set2 has a child tag with an alt attribute content which is blacklisted or that only contains non alphanumerical characters)

NMI :

In all other cases

Notes

We assume here that the image links with only one child of type img or object