EARL - relationships to TAG

[Kevin Looney <Kevin.T.Looney@Sun.COM>]

Hi everyone,

    I had a homework item to look into the descriptions of a W3C 
proposal called EARL

(Requirements: 
http://www.w3.org/WAI/ER/EARL10/WD-EARL10-Requirements-20050415)

My general impressions are below.

Regards,
Kevin L

=======================================================================================

EARL seems to be a *very* simple test description language - motivated 
by a need to describe resource evaluations in the domain of Software 
Accessibility.  The Schema description (http://www.w3.org/TR/EARL10/)  
and Guide description 
(http://www.w3.org/WAI/ER/EARL10/WD-EARL10-Guide-20090702) seems to 
define the purpose differently:

"The Evaluation and Report Language (EARL) defines a vocabulary for 
expressing test results. It enables any person, software application, or 
organization to assert test results for any test subject tested against 
any set of criteria. The test subject might be a Web site, an authoring 
tool, a user agent, or some other entity. The set of criteria may be 
accessibility guidelines, formal grammars, or other types of quality 
assurance requirements.    ....  EARL is not a comprehensive vocabulary 
for describing test procedures, test criteria, or test requirements but, 
rather, for describing the outcomes from such testing."

EARL tries to document:

1.) An Asserter
2.) What is being asserted


Classes can hang from this:
a.) Test Case
b.) Test Criteria
c.) Exclusion

As well as properties:
d.) suite
e.) id
f.) excludes
g.) level
h.) result property

See Model Primer, http://infomesh.net/2001/05/earl/model/primer/ for 
examples.

General
==========
Where TAG is intent on describing a general way to 'mark-up' a 
specification into statements of "asserted behavior", EARL is more 
focused on generalizing how to describe Test Results.  EARL's goals in 
doing this is to provide a common language for Test Results from various 
sources to be described uniformly.

There is some overlap in what is being described by our two systems - eg 
Some behavior being asserted (in a simple way), TAG is much more focused 
on describing 'the context' of asserted behavior (pre-conditions, 
pre-requisites, assertion location), organization  (assertion location, 
spec document), and conformance description.  EARL seems to be more 
concerned about capturing requirements from any generic source of 
requirements (Document, Person (word of mouth), as well as who is doing 
the testing.

Both groups seem to be encoding their descriptions in some form of XML 
Schema.