ISO/IEC 13673:2000
(Main)Information technology — Document processing and related communication — Conformance testing for Standard Generalized Markup Language (SGML) systems
Information technology — Document processing and related communication — Conformance testing for Standard Generalized Markup Language (SGML) systems
standard addresses the construction and use of test suites for verifying conformance of SGML systems. Its provisions assist those who build test suites, those who build SGML systems to be evaluated by such suites, and those who examine an SGML system's performance on a test suite as part of the process of selecting an SGML tool. In particular, this standard includes: ? criteria for the organization of test suites, including naming conventions, documentation conventions, and specification of applicable concrete syntaxes and features. Among other advantages, these conventions facilitate any non-SGML automatic processing that may be convenient for the developers or the users of the tests; NOTE ? An example of such non-SGML processing is sorting tests by name. ? a standard form for describing test results that makes clear what has been proven or disproven by the tests; ? the specification of a Reference Application for SGML Testing (RAST) that interprets all markup to allow machine comparison of test results for documents conforming to ISO 8879. RAST indicates in a standard way when tags, processing instructions, and data are recognized by the parser, replacing references and processing markup declarations and marked sections appropriately. RAST tests information likely to be passed by a general-purpose SGML parser to an application but does not test additional information that some parsers provide; ? the specification of a Reference Application for Capacity Testing (RACT) that reports a validating parser's capacity calculations. An SGML systemthat supports this application indicates its ability to report capacity errors regardless of whether it supports variant capacity sets; ? the specification of test procedures related to SDIF data streams. This standard applies to the testing only of aspects of SGML implementation and usage for which objective conformance criteria are defined in ISO 8879. NOTE ? Among the aspects of an SGML system not addressed by this standard are error recovery, phrasing of error messages, application results, and documentation (including the system declaration).
Technologies de l'information — Traitement documentaire et communication connexe — Tests de conformité pour langage normalisé de balisage généralisé (SGML)
General Information
Standards Content (Sample)
INTERNATIONAL ISO/IEC
13673
STANDARD
First edition
2000-05-01
Information technology — Document
processing and related communication —
Conformance testing for Standard
Generalized Markup Language (SGML)
systems
Technologies de l’information — Traitement documentaire et communication
connexe — Tests de conformité pour langage normalisé de balisage
généralisé (SGML)
Reference number
ISO/IEC 13673:2000(E)
© ISO/IEC 2000
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ISO/IEC 13673:2000(E)
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ISO/IEC 13673:2000(E)
Contents
Page
1 Scope. 1
2 Normative references . 1
3 Precedence of ISO 8879 . 2
4 Definitions. 2
5 Use of SGML test suites. 3
6 Test suite documentation. 5
7 Types of tests . 7
8 General requirements for individual tests . 8
9 Test case naming conventions . 8
10 Requirements for SGML names and literals. 9
11 Conventions for testing string length . 9
12 Source document formatting conventions . 10
13 Test categories . 11
14 The Reference Application for SGML Testing (RAST) . 12
15 The Reference Application for Capacity Testing (RACT) . 19
16 Test suite reports. 20
17 Testing SDIF data streams. 21
Figure
1 A 240-character processing instruction . 10
Annexes
A The ISO 8879 Element Structure Information Set (ESIS). 23
B Sample tests and RAST results. 26
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ISO/IEC 13673:2000(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission)
form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC partici-
pate in the development of International Standards through technical committees established by the respective
organization to deal with particular fields of technical activity. ISO and IEC technical committees collaborate in fields
of mutual interest. Other international organizations, governmental and non-governmental, in liaison with ISO and
IEC, also take part in the work.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO/IEC 13673 was prepared by ANSI (as ANSI X3.190) and was adopted, under a special
“fast-track procedure”, by Joint Technical Committee ISO/IEC JTC 1, Information technology, in parallel with its
approval by national bodies of ISO and IEC.
Annex A forms a normative part of this International Standard. Annex B is for information only.
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ISO/IEC 13673:2000(E)
Introduction
ISO 8879:1986 and 8879:1986/A1:1988, Information processing – Text and office
systems – Standard Generalized Markup Language (SGML), define when a sys-
tem is a conforming SGML system. The determination of whether a system is a
conforming SGML system is of value both to potential users of such systems and
to their developers. This determination is, however, a complex process. To this
end, efforts are underway to develop test suites to validate conformance. Stan-
dardization of development and use of test suites assures consistency of results
and informs the public of the implications of the tests. Such formalism is provided
by this standard, which includes
– guidelines for the content of individual tests;
– rigorous conventions for naming test cases and the constructs used within
them;
– formatting and comment conventions;
– conventions for classifying test cases;
– conventions for documenting test suites;
– definition of a Reference Application for SGML Testing (RAST) that indicates
how an SGML parser interprets a test;
– definition of a Reference Application for Capacity Testing (RACT) that
reports a parser's capacity calculations;
– conventions for reporting a system's performance on a test suite.
This standard also addresses conformance to the related standard,
ISO 9069:1988, Information Processing – SGML support facilities – SGML Docu-
ment Interchange Format (SDIF), as SDIF is needed to connect the several entities
of an SGML document into a single object for interchange within OSI.
This standard may be used by those who develop SGML test suites, those who
build SGML systems to be evaluated by such suites, and those who examine an
SGML system's performance on a test suite as part of the process of selecting an
SGML tool.
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INTERNATIONAL STANDARD ISO/IEC 13673:2000(E)
Information technology — Document processing and
related communication — Conformance testing for
Standard Generalized Markup Language (SGML) systems
passed by a general-purpose SGML parser to an
1 Scope
application but does not test additional informa-
tion that some parsers provide;
This standard addresses the construction and use
of test suites for verifying conformance of SGML
– the specification of a Reference Application
systems. Its provisions assist those who build test
for Capacity Testing (RACT) that reports a vali-
suites, those who build SGML systems to be eval-
dating parser's capacity calculations. An SGML
uated by such suites, and those who examine an
system that supports this application indicates its
SGML system's performance on a test suite as part
ability to report capacity errors regardless of
of the process of selecting an SGML tool.
whether it supports variant capacity sets;
In particular, this standard includes:
– the specification of test procedures related to
– criteria for the organization of test suites,
SDIF data streams.
including naming conventions, documentation
This standard applies to the testing only of aspects
conventions, and specification of applicable con-
of SGML implementation and usage for which
crete syntaxes and features. Among other
objective conformance criteria are defined in
advantages, these conventions facilitate any
ISO 8879.
non-SGML automatic processing that may be
convenient for the developers or the users of the
NOTE – Among the aspects of an SGML system not
tests; addressed by this standard are error recovery, phras-
ing of error messages, application results, and
NOTE – An example of such non-SGML processing is
documentation (including the system declaration).
sorting tests by name.
– a standard form for describing test results
that makes clear what has been proven or dis-
2 Normative references
proven by the tests;
– the specification of a Reference Application The following normative documents contain provi-
for SGML Testing (RAST) that interprets all sions which, through reference in this text,
markup to allow machine comparison of test constitute provisions of this International Standard.
results for documents conforming to ISO 8879. For dated references, subsequent amendments to,
RAST indicates in a standard way when tags, or revisions of, any of these publications do not
processing instructions, and data are recognized apply. However, parties to agreements based on
by the parser, replacing references and process- this International Standard are encouraged to
ing markup declarations and marked sections investigate the possibility of applying the most
appropriately. RAST tests information likely to be recent editions of the normative documents indi-
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ISO/IEC 13673:2000(E)
cated below. For undated references, the latest 4.2 application modules: Components of an
edition of the normative document referred to SGML system other than the parser and entity
applies. Members of ISO and IEC maintain manager.
registers of currently valid International Standards.
4.3 effective edition: The current edition of a
standard including any amendments, addenda, or
ISO 646:1983, Information processing – ISO 7-bit
other modifications.
coded character set for information interchange
4.4 Element Structure Information Set: Infor-
ISO 8879:1986, Information processing – Text and
mation comprising the element structure that is
office systems – Standard Generalized Markup
described by SGML markup (the element structure
Language (SGML)
information set is defined in annex A).
ISO 8879:1986/A1:1988, Information processing –
4.5 ESIS: Element Structure Information Set.
Text and office systems – Standard Generalized
4.6 equivalent SGML documents: SGML doc-
Markup Language (SGML) Amendment 1
uments that, when parsed with respect to identical
ISO 9069:1988, Informationprocessing–SGML
DTDs and LPDs, have an identical ESIS.
support facilities – SGML Document Interchange
4.7 internal entity: An entity whose replacement
Format (SDIF)
text appears in an entity declaration.
4.8 lexicographic order: An order in which dis-
tinct strings are arranged by comparing successive
3 Precedence of ISO 8879
letters. One string appears before another if it is a
prefix of the second, or if, according to the following
Any discrepancy between any provision of this
conventions, in the first position where they differ,
standard and ISO 8879 should be resolved in
the character in the first string precedes the char-
accordance with the latter. Furthermore, should
acter in the second string. Printable characters
any future effective edition of ISO 8879 contradict
precede nonprintable characters. One printable
any provision of this standard, a test suite for the
character precedes another if the ISO 646 charac-
future version will be considered to conform to this
ter number of the first is smaller than the ISO 646
standard only if the discrepancy is resolved in
character number of the second. In particular, the
accordance with the effective edition of ISO 8879.
space character precedes all other printable char-
In particular, the precedence of ISO 8879 applies
acters and any other printable character precedes
to the definitions in clause 4, the description of
a second one if the first precedes the second char-
RAST in clause 14, and the description of ESIS in
acter in the list of printable characters given in
annex A.
4.14. A nonprintable character precedes another if
its character number in the document character set
Should there be any internal inconsistencies within
is smaller than the character number of the second
this standard between annex A and the remainder,
in the document character set.
implementors of conforming test suites shall rely
NOTE – For strings consisting only of printable char-
on the provisions in annex A.
acters, this order is independent of concrete syntax.
4.9 major SOO: A statement of objective for sev-
eral related tests in a test suite.
4 Definitions
4.10 markup-sensitive SGML application: An
SGML application that can act on SGML markup
NOTE – None of the terms defined below are used or
as well as element structure.
defined in ISO 8879. Should such definitions be
added to some future version of ISO 8879, the prece-
4.11 minor SOO: A statement of objective that
dence of ISO 8879 will apply in accordance with
clause 3.
describes the particular principle of the SGML lan-
guage that distinguishes an individual member of a
4.1 anomalous test case: A test case that devi-
group of related tests.
ates from some requirement of ordinary tests
because the tested SGML construct is incompati- 4.12 nonprintable character: A character that
ble with that requirement. is not a printable character (see 4.14).
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ISO/IEC 13673:2000(E)
4.13 ordinary test case: A test case that follows
5 Use of SGML test suites
the naming, organizing, and formatting conven-
tions itemized in this standard and identified as
Because of the wide variation possible in SGML
requirements for ordinary tests (see anomalous
systems, no single test suite is adequate for testing
test case).
how well all SGML systems conform to the require-
ments of ISO 8879. Some SGML systems produce
4.14 printable character: A character with
SGML documents, others process SGML docu-
ISO 646 character number in the range 32 to 126
ments to obtain various results, still others both
inclusive. These characters consist of the space
read and produce SGML documents. Some sys-
character and all the following:
tems are restricted to documents with particular
document type declarations, others can process
!"#$%&'()*+,-./012
arbitrary documents meeting the constraints of the
3456789:;<=>?@ABCD
system declaration. A test suite intended for a
EFGHIJKLMNOPQRSTUV
more general system contains test cases that can-
WXYZ[\]^_`abcdefgh not be processed by a more restrictive system; a
test suite for a restrictive system does not ade-
ijklmnopqrstuvwxyz
quately explore the capabilities of a more general
{|}~
one.
4.15 RACT: Reference Application for Capacity
NOTE – An SGML test suite indicates whether the
Testing.
modules of an SGML system that process SGML do
so according to the specifications of ISO 8879. Test-
4.16 RAST: Reference Application for SGML
ing a system's SGML capabilities does not indicate
whether it correctly performs a desired application in
Testing.
other respects.
4.17 Reference Application for Capacity
5.1 Comprehensive test suites
Testing: An SGML application that reports capac-
SGML test suites shall be comprehensive. A gen-
ity calculations (defined in clause 15).
eral-purpose SGML test suite shall provide tests
4.18 Reference Application for SGML
that explore conformance to every required aspect
Testing: An SGML application that reports ESIS
of the SGML language and to every aspect of sup-
information (defined in clause 14).
ported optional features. Similarly, a test suite for a
particular application shall provide tests to explore
4.19 SOO: Statement of objective.
every aspect of the SGML language used in that
application.
4.20 statement of objective: A brief description
of the aspect of the SGML language explored in an
NOTE – An application-specific test suite may not be
individual test case or a group of related tests. able to test all required constructs of SGML and can-
not indicate whether the underlying SGML parser
conforms to the requirements of ISO 8879 for such
4.21 structure-controlled SGML application:
constructs. For example, attributes cannot be tested if
an application does not happen to use any. Thus, a
An SGML application that operates only on ESIS
test suite for such an application cannot predict con-
information and the “APPINFO” parameter of the
formance of attribute handling in an implementation of
SGML declaration; a structure-controlled applica-
another application built with the same parser.
tion operates on the element structure described
This standard defines requirements for testing gen-
by SGML markup, never on the markup itself.
eral SGML systems. Test suites intended for more
restrictive environments may deviate from these
4.22 test case (or test): An SGML document
requirements only where the requirements are
included in a test suite.
incompatible with the system to be tested. For
4.23 tested system: An SGML system that is
example, the conventions for selecting generic
evaluated by inspection of the results it produces
identifiers cannot be followed in a system restricted
on the test cases of a test suite.
to a document type declaration that uses other
conventions.
4.24 test suite: A documented collection of
SGML documents intended to exercise an SGML A test suite for a validating SGML system shall
system in order to indicate whether the system include erroneous test cases to investigate com-
conforms to the specifications of ISO 8879. prehensively the system's ability to detect errors. A
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ISO/IEC 13673:2000(E)
nonvalidating SGML system can be tested with – The application's output is machine-readable
such a test suite, but its results on erroneous doc- (for example, it is a computer file rather than
uments are not predictable. printed paper or sound). Such applications
include, for example, one that counts the number
5.2 The role of SGML in a tested system
of elements in a document or one that produces
a vocabulary list of the unique words that occur
The way a test suite is used depends on whether
within the content of a document.
the tested system processes existing SGML docu-
ments, or produces SGML documents.
The test procedure involves comparing the appli-
cation's output on sets of equivalent, but not
5.2.1 Systems that read SGML
identical, SGML documents. Identical output must
A system that acts upon existing SGML documents
be produced for such documents. This criterion
is tested by examining the results it produces from
alone cannot demonstrate a system's conform-
every test in a comprehensive test suite. However,
ance to ISO 8879. For example, the criterion is
the variation in SGML systems means these
satisfied by a system that produces identical output
results may take any number of forms. As a result,
for all documents, equivalent or not. More informa-
there is no unique method for determining whether
tion is obtained if the application produces different
a tested system correctly processes a test case.
results for documents that are not equivalent. Note,
however, that the simple word-list application just
The remainder of this subsubclause discusses var-
described does not meet this stricter constraint,
ious methods for evaluating test suite results
since there could be documents with very different
produced by a system that processes SGML docu-
element structure that use the same vocabulary.
ments. Of these methods, RAST provides the most
information and should be used whenever
NOTE – Implementors of test suites that consist of
sets of equivalent documents should verify that mem-
possible.
bers of each set are indeed equivalent by confirming
that RAST produces the same output for every mem-
5.2.1.1 Evaluating with RAST
ber in the set.
RAST (see clause 14) is a simple SGML applica-
5.2.1.3 Evaluation through error recognition
tion designed to validate a parser's recognition of
the Element Structure Information Set (ESIS). The correctness of a validating SGML parser can,
ESIS (see annex A) is the information exchanged in large measure, be demonstrated if the parser
by a parser and other components of a program a) reports erroneous SGML documents to be
that implements a structure-controlled application. invalid and b) reports valid documents to be con-
RAST reflects the ESIS of an SGML document with forming. This type of testing can be done
a minimal amount of additional information in such regardless of how errors are reported (possibilities
a way that the results it produces from two SGML include visual and auditory signals as well as error
documents using the same concrete syntax will be messages). However, some aspects of SGML
the same if and only if the two documents have the parsing – for instance, significance of record ends
sameESIS.AnSGMLsystemthatsupports RAST and correct interpretation of default attribute values
is easily tested by machine comparison of RAST – do not affect whether the document is valid and
results to known correct RAST output for every hence cannot be tested in this way. Comprehen-
document in a test suite. sive testing of markup minimization in this manner
is also difficult. Furthermore, a system that reports
NOTE – There is no requirement that an SGML sys-
an erroneous document to be in error need not be
tem support RAST. However, it should be easy to
implement RAST with any general-purpose SGML conforming; the system may have accepted the
system that provides a software-development envi-
erroneous construct and misinterpreted some cor-
ronment for building SGML applications.
rect markup.
5.2.1.2 Comparing with equivalent
5.2.1.4 Other forms of evaluation
documents
Knowledge of particular applications can be used
An SGML system that does not support RAST can
to design system-specific methods of reporting all
be tested to some extent through a structure-con-
or part of the ESIS information in a document. The
trolled application with the following properties:
reported information is an indication of the con-
– The application is not restricted to one or formance of the tested system's parser to
more specified document type definitions; ISO 8879.
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ISO/IEC 13673:2000(E)
5.2.2 Systems that generate SGML
6 Test suite documentation
A system that produces SGML documents is
This clause describes information that shall be
tested by processing representative output with a
included in the documentation that accompanies a
system that reads SGML documents. A test suite
test suite. This information shall be available to all
therefore consists of test cases that produce a potential and actual users of the test suite and shall
comprehensive collection of output documents. be repeated in any report generated after a system
is tested.
NOTE – This procedure shows whether the tested
6.1 General documentation
system produces conforming SGML documents from
the test cases; it provides no information about
The documentation shall include the following:
whether the output is correct in other respects.
– one or more identifiers, such as ISO
5.2.3 Systems that both read and produce
8879:1986(E) or ISO 8879:1986/A1:1988(E),
SGML
indicating the effective edition of ISO 8879 used
in preparing the test suite;
A system that both processes and generates
SGML documents can be tested separately as a
– one or more identifiers, such as ISO/
system that reads SGML and as one that produces IEC 13673:2000(E), indicating the effective edi-
SGML. Depending on the relationship between the tion of this standard used in preparing the test
suite and in any implementations of RAST and
input and output documents, a comparison of the
RACT used to generate results of those applica-
two may provide additional results. Although such
tions provided with the test suite;
a comparison is application dependent, it may
reveal information about SGML conformance. One
– the following statement, translated if the doc-
form of comparison is testing whether input and
ument is not in English:
output are equivalent SGML documents (which
AtestsuitecanindicatethatanSGMLsystemis
can be done by a character-by-character compari-
nonconforming by providing a test on which the
son of their RAST results). This comparison is
system fails. However, no test suite can prove
useful, for example, in testing a text editor that can
that an SGML system is fully conforming or
both import and export SGML documents. Such an
predict the results the system would obtain on
editor's SGML parsing can be tested by importing
untested documents.
each test in a test suite and immediately exporting
the unedited document; the result should be an
– the following statement, translated if the doc-
equivalent document. Similarly, a tool that replaces
ument is not in English:
a minimal SGML document with an equivalent one
When a tested system produces results other
using various forms of markup minimization should
than those expected by a test suite, the
produce output equivalent to its input. For some
discrepancy may result from an error in either
applications, it may be useful to verify that input
the test suite or the tested SGML system.
and output are identical. Other forms of compari-
son depend on particular applications.
– a description of the types of SGML system
that can be tested by the test suite. This descrip-
5.2.4 Systems that use SGML as an interme-
tion, for example, indicates whether the test suite
diate form
is restricted to a particular application. It also
identifies any provisions of this standard that
Asystemmay useSGMLevenifbothits original
could not be observed – naming conventions
input and final output have some other form. Such
that are incompatible with an application's docu-
a system creates an SGML document and then
ment type declaration, for instance;
processes it to obtain another result. Depending on
– indication of whether the test suite explores
the implementation, it may be possible to test the
validation as well as conformance of SGML doc-
embedded SGML parser in another application.
uments; in other words, whether some test
Furthermore, if the intermediate SGML document
cases are deliberately erroneous documents;
can be saved, the system can be evaluated as a
system that produces SGML. In other cases, sys- – description of the document character sets
tem-specific testing is required. used in the test suite in the syntax of the docu-
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ISO/IEC 13673:2000(E)
ment character set parameter of the SGML mentation of RAST that generated the results
declaration, with descriptive comments, if is capable of producing the error indication,
desired; #ERROR (see 14.6.2);
– a list of all optional SGML features
– indication of whether the test suite provides
addressed by the test suite in the syntax of the
RACT results for individual tests;
feature use parameter of the system declaration,
– the number of test cases in each category
with descriptive comments, if desired;
listed in clause 13, as well as identification of any
– a list of all optional SGML features not cov-
new categories defined for this test suite, with
ered by the test suite, with a statement that the
the number of test cases in each.
results do not predict the tested system's perfor-
6.2 Test case documentation
mance on documents using these features. The
list is presented in the syntax of the feature use
The documentation shall also include a statement
parameter of the system declaration,with
of objective (SOO) for each test. The SOO
descriptive comments, if desired;
describes the primary aspect of the SGML lan-
guage described in the test case. SOOs are clear
– a description of the concrete syntaxes
and concise statements, which may be direct quo-
included in the test suite in the syntax of the con-
tations from ISO 8879, possibly from syntax
crete syntax scope and concrete syntaxes
productions, notes, indented examples, or
supported parameters of the system declaration,
annexes. A test's SOO appears as a comment
with descriptive comments, if desired;
within the test case. Furthermore, the SOOs for all
– a description of the capacity sets included in
tests in the test suite shall be listed in a separate
the test suite in the syntax of the capacity set
report. The SOO report allows an individual to
parameter of the system declaration,with
review the scope and some of the accuracy
...
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