OWL Web Ontology Language
Test Cases

W3C Recommendation 10 February 2004

New Version Available: OWL 2 (Document Status Update, 12 November 2009)

The OWL Working Group has produced a W3C Recommendation for a new version of OWL which adds features to this 2004 version, while remaining compatible. Please see OWL 2 Document Overview for an introduction to OWL 2 and a guide to the OWL 2 document set.

This version:: http://www.w3.org/TR/2004/REC-owl-test-20040210/
Latest version:: http://www.w3.org/TR/owl-test/
Previous version:: http://www.w3.org/TR/2003/PR-owl-test-20031215/
Editors:: Jeremy J. Carroll, HP <jjc@hpl.hp.com>; Jos De Roo, AGFA,<jos.deroo@agfa.com>

Please refer to the errata for this document, which may include some normative corrections.

This normative version is a compound document. Non-normative versions consisting of a single HTML file are available in three sizes: medium, large, and extra large. The tests of this document are also available in these non-normative formats: Zip archive of approved tests, the test Web site.

See also translations.

Abstract

This document contains and presents test cases for the Web Ontology Language (OWL) approved by the Web Ontology Working Group. Many of the test cases illustrate the correct usage of the Web Ontology Language (OWL), and the formal meaning of its constructs. Other test cases illustrate the resolution of issues considered by the Working Group. Conformance for OWL documents and OWL document checkers is specified.

Status of this document

This document has been reviewed by W3C Members and other interested parties, and it has been endorsed by the Director as a W3C Recommendation. W3C's role in making the Recommendation is to draw attention to the specification and to promote its widespread deployment. This enhances the functionality and interoperability of the Web.

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

1. Introduction

As part of the definition of the Web Ontology Language (OWL) the Web Ontology Working Group provides a set of test cases. This document presents those test cases. They are intended to provide examples for, and clarification of, the normative definition of OWL found in [OWL Semantics and Abstract Syntax] to which this document is subsidiary.

This document is one component of the description of OWL, the Web Ontology Language, being produced by the W3C Web Ontology Working Group. The Document Roadmap section of the [OWL Overview] describes each of the different parts and how they fit together.

This document describes the various types of test used and the format in which the tests are presented. Alternative formats of the test collection are provided. These are intended to be suitable for use by OWL developers in test harnesses, possibly as part of a test driven development process, such as Extreme Programming [XP]. The format of the Manifest files used as part of these alternative formats is described.

In the non-normative appendices, this document also describes the process for creation and approval of these tests.

1.1. Conformance and Scope

However, the test cases do not constitute a conformance test suite for OWL, since they are silent on several important issues. This document cannot be considered a complete specification of OWL.

The tests illustrate issue resolutions, and illustrate the use and meaning of the terms in the OWL namespace.

There are other miscellaneous tests: some arising in the literature, and in preexisting systems; others intending to show the difficulty of complete implementations of OWL Full.

2. Deliverables (Normative)

Note: Other files can be found under the top URL of the Web site which are not part of the deliverable.

2.1. Normative Status

Of the deliverables the only normative tests are those included in this document. All other deliverables are informative. Moreover, the recommendation document is informative except for the conformance statements, the test data (specified in RDF/XML [RDF Syntax]), and the supporting documentation.

2.2. Extra Credit Tests

The Web Ontology Working Group has seen adequate implementation experience of most of the tests in this document. Some, however, are particularly difficult to implement efficiently. These are labelled as extra credit tests. Such tests indicate the semantics of OWL, but may use features that are not sufficiently widely implemented to provide good interoperability.

A general case of extra credit tests is that all OWL Full nonentailments and consistency tests are extra credit tests. This is because typical OWL Full implementations prove entailments but cannot prove nonentailments.

Extra credit tests are labelled with "EC" within this document and with status EXTRACREDIT in the manifest files.

The name indicates that there is no expectation that any implementation will successfully run such tests and any that do gain extra credit.

3. Test Types (Normative)

Each test consists of one or more RDF/XML documents and a Manifest file. Tests of one document indicate some property of that document when viewed as an OWL knowledge base. Tests of two or more documents indicate a relationship between the two documents when viewed as OWL knowledge bases.

The Manifest file is named ManifestNNN.rdf (The NNN is replaced by the test number). It contains metadata (in RDF) indicating the test type, and describing the test.

The metadata also indicates the language levels appropriate for each test and each document in each test. For each RDF/XML document, one language level is indicated, being OWL Lite, OWL DL or OWL Full, as given by the syntactic rules in [OWL Semantics and Abstract Syntax]. For semantic tests, one or two language levels are indicated. If the language level OWL Full is indicated for a semantic test, then the test holds according to the RDF-Compatible Model-Theoretic Semantics in [OWL Semantics and Abstract Syntax]. If the language level OWL Lite or OWL DL is indicated for a semantic test, then the test holds according to the Direct Model-Theoretic Semantics in [OWL Semantics and Abstract Syntax]. If the language level OWL Lite is indicated for a semantic test, then the test only uses features within the OWL Lite sublanguage.

Some of the tests require that certain datatypes are, or are not, supported in the datatype map [OWL Semantics and Abstract Syntax]. These are indicated with the test. Other datatypes which are used in the test are also indicated: the test applies whether or not these are supported in the datatype map . The datatypes xsd:integer, xsd:string from [XML Schema Datatypes] are not indicated, even when used or required, since they must be supported.

3.1. Tests for Incorrect Use of OWL Namespace

These tests use one document. It is named badNNN.rdf. This document includes a use of the OWL namespace with a local name that is not defined by the OWL recommendation. An OWL Syntax checker SHOULD give a warning.

Note: These tests are intended to help migration from DAML+OIL [DAML+OIL], since the local names chosen are defined in the DAML+OIL namespace.

3.2. Entailment Tests

These tests use two documents. One is named premisesNNN.rdf, the other is named conclusionsNNN.rdf. The conclusions are entailed by the premises. Such entailment is defined by the OWL semantics [OWL Semantics and Abstract Syntax], (see also OWL Full entailment).

3.3. Non-Entailment Tests

These tests use two documents. One is named premisesNNN.rdf, the other is named nonconclusionsNNN.rdf. The nonconclusions are not entailed by the premises. Such entailment is defined by the OWL semantics [OWL Semantics and Abstract Syntax], (see also OWL Full entailment).

3.4. True Tests

These tests use one document. It is named conclusionsNNN.rdf. The conclusions follow from the OWL semantics [OWL Semantics and Abstract Syntax]. These tests are a special case of the entailment tests in which the premises are empty.

3.5. OWL for OWL Tests

These tests use one document. It is named conclusionsNNN.rdf. These are a special case of true tests. The conclusions follow from the OWL Full semantics [OWL Semantics and Abstract Syntax]. The tests are intended to illustrate how OWL Full can be used to describe its own properties and classes.

3.6. Consistency Tests

3.7. Inconsistency Tests

3.8. Import Entailment Tests

These tests use more than two documents. One is named premisesNNN.rdf, another is named conclusionsNNN.rdf, the rest have names like supportNNN-A.rdf. The support documents are in the imports closure of the premises document. The conclusions are entailed by the imports closure of the premises. Such entailment is defined by the OWL semantics [OWL Semantics and Abstract Syntax], (see also OWL Full entailment).

3.9. Import Level Tests

These tests use two documents. One is named importsNNN.rdf, the other is named mainNNN.rdf. These tests indicate the interaction between owl:imports and the sublanguage levels of the main document.

4. Conformance (Normative)

4.1. Document Conformance

4.1.1. Syntactic Conformance

4.1.2. Semantic Conformance

4.2. Document Checker Conformance

4.2.1. Syntax Checker

An OWL syntax checker takes a document as input, and returns one word being one of Lite, DL, Full, Other.

In addition, an OWL Syntax Checker SHOULD report a warning if the RDF graph [RDF Concepts] corresponding to the document uses any URI references starting with the prefix http://www.w3.org/2002/07/owl# except those found in the [RDF Schema for OWL].

An OWL syntax checker SHOULD report network errors occurring during the computation of the imports closure.

4.2.2. Consistency Checker

An OWL consistency checker takes a document as input, and returns one word being Consistent, Inconsistent, or Unknown.

An OWL consistency checker SHOULD report network errors occurring during the computation of the imports closure.

An OWL consistency checker MUST be sound: it MUST return Consistent only when the input document is consistent and Inconsistent only when the input document is not consistent, with respect to the datatype map of the checker.

An OWL consistency checker is complete and terminating, if, given sufficient (but finite) resources (CPU cycles and memory) and the absence of network errors, it will always return either Consistent or Inconsistent. It has been shown that for OWL Lite and DL it is possible to construct a complete and terminating consistency checker (the languages are decidable), and that for OWL full it is not possible to construct a complete and terminating consistency checker (the language is undecidable, [Practical Reasoning]).

An OWL consistency checker SHOULD NOT return Unknown. Unknown, while sometimes needed, is not a desired response.

5. Testing an OWL Implementation (Informative)

5.1. OWL Syntax Checkers

5.2. OWL Consistency Checker

An OWL consistency checker can be tested using appropriate consistency and inconsistency tests. Appropriate tests are those of an appropriate level and for which the checker has appropriate datatype support. The level of the test indicates the semantic theory being used, which may differ from the level of the file. For example, test Thing-004 contains an OWL DL file which is consistent as an OWL DL consistency test, but inconsistent as an OWL Full consistency test.

The above constraints also apply to extra credit tests. Consistency checkers that return the correct answer (i.e. not Unknown) gain the extra credit.

6. Manifest Files (Informative)

The Manifest file follows the RDF schema developed for the RDF Test Cases [RDF Tests].

Specifically each test has its own Manifest file, and is identified from the URI reference formed from the Manifest file's URL with a fragment test.

Where otest is bound to http://www.w3.org/2002/03owlt/testOntology# and rtest is bound to http://www.w3.org/2000/10/rdf-tests/rdfcore/testSchema#.

The name of the original author of the test is shown using a dc:creator property, see [Dublin Core].

A description of the test is given (using XHTML markup [XHTML]) as the value of the rtest:description property.

An issue, if any, from the OWL Issues list [OWL Issues], is the value of a rtest:issue property.

An appropriate language feature, from the OWL namespace, if any, is the value of the otest:feature property.

The input documents with the test data are found as the value of the rtest:inputDocument property or as the value of both the rtest:premiseDocument and the rtest:conclusionDocument. The support files for import entailment tests, import level tests and test imports-002 are found as the values of otest:importedPremiseDocument.

The conformance levels associated with both files and tests are given with the otest:level property. The value for each document is one of otest:Full, otest:DL, otest:Lite or otest:Other. Each test is explicitly associated with one or two levels. If it is associated with otest:Lite then it is implicitly suitable for otest:DL.

The datatypes used in the test are given with the otest:usedDatatype property or with one of its subproperties: otest:supportedDatatype or otest:notSupportedDatatype. These indicate that the test is only valid when the datatype is supported or not supported respectively by the datatype map being used.

The rtest:status of the test reflects the process of appendix A. It is given as one of the following levels:

7. The OWL Tests (Normative)

7.3. Additional Description Logic Tests

These tests are ones that are either known from the literature (for instance, from [Heinsohn et al.]), or from test suites contributed by Network Inference, or developed by the Working Group.

7.4. Miscellaneous Tests

These tests are ones that do not fit any other category. Some are taken from the [OWL Guide]; others reflect various aspects of OWL, that were not formal issues addressed by the Working Group.

7.5. Extra Credit

There is no expectation that any implementation will successfully run the tests in this section; any that do gain extra credit.

The intent is to illustrate the semantics of OWL, particularly OWL Full, as specified by [OWL Semantics and Abstract Syntax], with the specific goal of showing that it is possible to say things that it is not reasonable to expect an implementation to completely understand.

A. Test Creation, Approval and Modification (Historical, Informative)

This appendix describes the process that was used during the development of this test suite.

A.1. Creation

Tests are created by members of the Working Group. An (optional) test editor is provided to facilitate this. Tests are then placed in the appropriate directory in the test Web site. This is done using CVS access to the W3C CVS server [W3C CVS].

When created, tests are given a status of "PROPOSED". The author of the test creates a Manifest file in the directory of the new test, identifying:

A.2. Approval

At the chair's discretion, individual tests or groups of tests are put to the Working Group in the weekly telecon or at a face-to-face meeting.

Tests are approved by Working Group decision, with status 'APPROVED' or 'EXTRACREDIT'.

The Working Group may take account of favorable review of the tests and/or implementation reports, as well as other factors.

If the Working Group approves a test, then it is included in the test case document.

The Working Group may reject a test, in which case its status is changed to "REJECTED". This does not indicate that the converse of the test has been accepted. There may be stylistic or other grounds for rejecting technically correct tests.

The Working Group has complete discretion to approve or reject tests independent of their conformance with this process or their conformance with the OWL Working Drafts.

In the light of new information, and at the chairs' discretion, the Working Group may review any previous decision regarding any test cases. The status of "OBSOLETED" may be used where a test has ceased to be appropriate.

A.3. Modification

The editors may make editorial changes to approved and proposed tests. This includes:

B. Stylistic Preferences (Informative)

There is a preference for the following stylistic rules. None of these rules is obligatory, but test authors should be minded that it will be easier to gain Working Group consensus if they follow these rules.

B.1. Use of RDF/XML

B.2. Use of xml:base

Test and manifest files should have an xml:base attribute [XMLBASE] on the document element. This should show the preferred URL of the document, from which it is actually retrievable.

B.3. Use of .rdf Suffix

Test and manifest files should use the ".rdf" suffix. URIs should not. The URL used for xml:base declarations does not have a suffix.

B.4. Use of example Domains

All URLs in the test and manifest files should be retrievable Web resources except for those that use domain names with "example" as the penultimate component (e.g. "http://www.example.org/ontology#prop").

B.5. Copyright

The following copyright statement should be included as an XML comment in every test file:

B.6. Description

The description should be included as an XML comment in each test file, and be included as RDF content in the Manifest file.

B.7. Directory Structure

Tests that relate principally to some owl property or class, should be put in a directory named using the local name of that property of class.

Otherwise, tests that relate to an issue should be put in a directory named like I3.4 where the issue number is taken from the OWL issue list [OWL Issues].

B.8. Test Numbering

Each file in a test should have the number of the test at the end of its name, before the suffix.

Note: the approved tests in a directory will not necessarily be contiguously numbered.

B.9. Triple Format of Test Data

Both the approved and proposed tests are shown both in RDF/XML, which is their normative form, and in a triples format. This lists the triples as subject, predicate and object, similar to the N-triples format described in [RDF Tests]. The following additional conventions are used:

In the N3 syntax [N3] used for namespace declarations, the first four appear as follows:

D. Acknowledgments (Informative)

The following people have contributed tests to this document: Sean Bechhofer, Ian Horrocks, Peter F. Patel-Schneider, Jeff Heflin, Dan Connolly, the Guide editors, Jonathan Borden, Charles White, Martin Dürst, Masayasu Ishikawa, Jim Hendler, Herman ter Horst, Dave Reynolds, and the editors.

Sandro Hawke created the tests results page, that has been a great help during the Candidate Recommendation phase.

We thank those who gave test reports and other feedback during the Candidate Recommendation: Ken Baclawski, Sean Bechhofer, Ian Dickinson, Michael Grove, Sandro Hawke, Ian Horrocks, Minsu Jang, Gary Ng, Mehrdad Omidvari, Bijan Parsia, Peter F. Patel-Schneider, Dave Reynolds, Rob Shearer, Evren Sirin, Charles White and Youyong Zou. We also thank the many others who helped develop the systems which produced these reports.

This document is the result of extensive discussions within the Web Ontology Working Group as a whole. The partipants in this Working Group included: Yasser alSafadi, Jean-François Baget, James Barnette, Sean Bechhofer, Jonathan Borden, Stephen Buswell, Jeremy Carroll, Dan Connolly, Peter Crowther, Jonathan Dale, Jos De Roo, David De Roure, Mike Dean, Larry Eshelman, Jérôme Euzenat, Tim Finin, Nicholas Gibbins, Sandro Hawke, Patrick Hayes, Jeff Heflin, Ziv Hellman, James Hendler, Bernard Horan, Masahiro Hori, Ian Horrocks, Jane Hunter, Rüdiger Klein, Natasha Kravtsova, Ora Lassila, Deborah McGuinness, Enrico Motta, Leo Obrst, Mehrdad Omidvari, Martin Pike, Marwan Sabbouh, Guus Schreiber, Noboru Shimizu, Michael K. Smith, John Stanton, Lynn Andrea Stein, Herman ter Horst, David Trastour, Frank van Harmelen, Bernard Vatant, Raphael Volz, Evan Wallace, Christopher Welty, Charles White, Frederik Brysse, Francesco Iannuzzelli, Massimo Marchiori, Michael Sintek and John Yanosy.

E. Changes Since Proposed Recommendation

The term datatype map is used instead of the term datatype theory, for consistency with the OWL and RDF Semantics. This occurred a number of times, including in the descriptions of tests miscellaneous-204, miscellaneous-205 and I5.8-012. The last of these consequentially required other minor rephrasing.

Added a paragraph near end of section 4.2.2, clarifying that a datatype map of an OWL Full consistency checker, (being a datatype map from RDF Semantics) "MUST" contain an entry for rdf:XMLLiteral. This makes explicit a requirement that was already implicit in the PR document. Also clarified that the datatype map in the definition of an OWL Full consistent document is as defined in RDF Semantics, by changing the link.

Consequentially, made explicit reference to RDF Semantics (this reference was implicit in the OWL Test Proposed Recommendation).

Corrected an error in the metadata of test miscellaneous-205 which is not applicable for OWL Full, since rdf:XMLLiteral is a required datatype for OWL Full. This change is visible as the deletion of the word "Full" from the header of the test.

This error in the OWL Test Candidate and Proposed Recommendation appears to have been relatively benign: