[xml/sgml-pkgs] Bug#686820: xmllint: Please make xmllint detect more bugs with indexterm ranges in docbook files

[Petter Reinholdtsen]

Package: libxml2-utils
Version: 2.7.8.dfsg-2+squeeze5

When checking docbook XML files, there are a few errors in the indexterm
entries that are undetected.  It will detect if there is a endofrange
entry without the corresponding startofrange.  It will also detect if
there are two startofrange with the same ID.  But it will not detect

 (1) if there is a startofrange without a endofrange.
 (2) if there are two endofrange with the same ID.

See the example docbook file for a demonstration.  This file got two
errors, and xmllint claim everything is OK.  I run it like this:

  xmllint --nonet --noout  --xinclude --postvalid  bad-indexterm.xml

Can xmllint be extended to detect these bugs too?  When adding lots of
indexterm entries it would be useful to get more help to find the bugs I
introduce. :)

<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
<!-- Demonstrate insufficient indexterm checking by xmllint. -->
<book>
  <bookinfo>
    <title>Example demonstrating xmllint index problem</title>
  </bookinfo>
<preface>
<title>test</title>
<indexterm id='idxone' class='startofrange'><primary>first index</primary></indexterm>
<para>test</para>
<indexterm startref='idxone' class='endofrange'/>
<indexterm startref='idxone' class='endofrange'/>
<indexterm id='idxtwo' class='startofrange'><primary>second index</primary></indexterm>
  <para>text is good</para>
</preface>
<index></index>
</book>

-- 
Happy hacking
Petter Reinholdtsen