Test Case sc4.1.1_l1_001: Well-formedness error: overlapping elements

Formal Metadata

Formal Metadata
TitleWell-formedness error: overlapping elements
DescriptionAn XHTML file that is not well-formed because the em and strong elements overlap while they should nest. This makes the structure ambiguous and might cause problems, for example for IBM Home Page Reader (see 'HTML 4.01 validity errors' at http://www.w3.org/2005/Talks/0908-wcag/validity-errors.html. (As a consequence of this ambiguity, some user agents may render the order of the words in the sentence in an order that does not make sense.)
CreatorBenToWeb (Christophe.Strobbe@…)
RightsCopyright BenToWeb 2005-2007
LanguageEnglish
Date2005-10-04
Statusvalidated

Technologies and Features

Technologies are markup languages or data formats. If the technology is a markup language, “features” refers to elements and attributes.

XHTML™ 1.0 The Extensible HyperText Markup Language (Second Edition)

XHTML™ 1.0 The Extensible HyperText Markup Language (Second Edition)

Feature: em (namespace: http://www.w3.org/1999/xhtml) .

Technical specification: Documents must be well-formed .

Feature: strong (namespace: http://www.w3.org/1999/xhtml) .

Technical specification: Documents must be well-formed .

Test Data

Purpose

This test case is intended to fail because the markup is ambiguous and may cause problems for assistive technologies.

Test Modes

Accessibility expert.

Test Files

Test file.

TCDL Data

sc4.1.1_l1_001 (XML).

Rules

“Rules” refer to success criteria in WCAG 2.0, checkpoints in WCAG 1.0 and similar requirements.

Primary Rules

The test case fails the following success criterion at line 9, column 15: http://www.w3.org/TR/2007/WD-WCAG20-20070517/Overview.html#ensure-compat-parses.

Functional Outcome

The syntax of the document is not correct; the content may be rendered in an incorrect order. IBM Home Page Reader 3.0 reads: If you have nothing then don't say it to say.

Technical Comment

The document is not well-formed: the strong element is not completely nested inside the em element. See 'Common HTML 4.01 validity errors and their effect on accessibility' at http://www.w3.org/2005/Talks/0908-wcag/validity-errors.html and 'Tag Soup: How UAs handle <x> <y> </x> </y>' at http://ln.hixie.ch/?start=1037910467&count=1.

This test case maps to failure F70: Failure of SC 4.1.1 due to incorrect use of start and end tags or attribute markup.

Secondary Rules

Secondary Rule (WCAG 2.0 - April 2006 Working Draft (Last Call))

The test case fails the following success criterion at line 9, column 15: http://www.w3.org/TR/2006/WD-WCAG20-20060427/guidelines.html#ensure-compat-parses.

Functional Outcome

The syntax of the document is not correct; the content may be rendered in an incorrect order. IBM Home Page Reader 3.0 reads: If you have nothing then don't say it to say.

Technical Comment

Online version: sc4.1.1_l1_001.

The document is not well-formed: the strong element is not completely nested inside the em element. See 'Common HTML 4.01 validity errors and their effect on accessibility' at http://www.w3.org/2005/Talks/0908-wcag/validity-errors.html and 'Tag Soup: How UAs handle <x> <y> </x> </y>' at http://ln.hixie.ch/?start=1037910467&count=1.

Secondary Rule (WCAG 2.0 - February 2005 Editor's Draft)

The test case fails the following success criterion at line 9, column 15: http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-20050211/#4.1_use-spec-avoid-spec-no-exception.

Functional Outcome

The syntax of the document is not correct; the content may be rendered in an incorrect order.

Technical Comment

The document is not well-formed: the strong element is not completely nested inside the em element. See 'Common HTML 4.01 validity errors and their effect on accessibility' at http://www.w3.org/2005/Talks/0908-wcag/validity-errors.html and 'Tag Soup: How UAs handle <x> <y> </x> </y>' at http://ln.hixie.ch/?start=1037910467&count=1.