Rule 1.3.3

Summary

This test consists in checking whether each button associated with an image that handles information has a relevant alternative.

Business description

Criterion

1.3

Test

1.3.3

Description

Pour chaque bouton associé à une image (balise input avec l'attribut type="image") ayant un attribut alt, le contenu de cet attribut est-il pertinent (hors cas particuliers) ?

Level

A

Technical description

Scope

page

Decision level

Semi-decidable

Algorithm

Selection

Set1

All the <input> tags with a "type" attribute equals to "image" and an "alt" attribute (css selector : input[type=image][alt])

Process

Test1

For all elements of Set1, check whether the content of the "alt" attribute is not relevant (see Notes for details about relevancy test).

For each occurrence of true-result of Test1, raise a MessageA.

For each occurrence of false-result of Test1, raise a MessageB

MessageA
  • code : NotPertinentAlt
  • status: Failed
  • parameter : "alt" attribute, "src" attribute, tag name
  • present in source : yes
MessageB
  • code : CheckPertinenceOfAltAttributeOfInformativeImage
  • status: Pre-Qualified
  • parameter : "alt" attribute, "src" attribute, tag name
  • present in source : yes

Analysis

Failed

At least one <input> tag with a "type" attribute equals to "image" has an irrelevant "alt" attribute (Test1 returns true for at least one element)

Pre-qualified

The alternatives of all the <input> tags with a "type" attribute equals to "image" need to be manually checked (Test1 returns false for all the elements of Set1)

Not Applicable

The page has no <input> tag with a "type" attribute equals to "image" tag and an "alt" attribute (Set1 is empty)

Notes

The content of the "alt" attribute is seen as not relevant if :

  • empty
  • only composed of non-alphanumerical characters
  • identical to the "src" attribute
  • it has an extension of image type (loaded by the nomenclature named ImageFileExtensions composed of : jpg, gif, jpeg, png, bmp)