Re: nested tags in glossary entries in html docs

[Erik Wienhold]

On 2024-04-12 18:29 +0200, Anton Voloshin wrote:
> In REL_13_STABLE and above, generated HTML have a broken HTML: nested <a
> href="..."> tags for all links to glossary. Somehow, this results in
> duplicated <a> tags on the https://www.postgresql.org/docs/
> 
> Found by tab-navigating https://www.postgresql.org/docs/16/rowtypes.html
> where we see (spacing added to avoid line wraps):
> ... create a <a class="glossterm"
> href="glossary.html#GLOSSARY-DOMAIN"</a><a class="glossterm"
> href="glossary.html#GLOSSARY-DOMAIN"
> title="Domain">domain</a> over the composite type ...
> 
> So, empty <a>, and then the real <a>. This resulted in stopping twice on the
> "domain" link (right before, and then on the
> "domain" word itself) while tab-navigating.

There's this bug[1] in the DocBook XSLT stylesheets.  Looks like the
fix[2] landed in 1.79.2 (latest version on Arch, matching the latest
snapshot on GitHub from 2020-06-03) because I can see the change in
/usr/share/xml/docbook/xsl-stylesheets-1.79.2-nons/html/inline.xsl and
/usr/share/xml/docbook/xsl-stylesheets-1.79.2-nons/xhtml/inline.xsl.
But I still get those nested <a> with a simple test:

    <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
              "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd";>
    <book>
     <title>Test</title>
     <glosslist>
      <glossentry id="glossary-a">
       <glossterm>A</glossterm>
       <glossdef>
        <para>
         <glossterm linkend="glossary-b">B</glossterm>
        </para>
       </glossdef>
      </glossentry>
      <glossentry id="glossary-b">
       <glossterm>B</glossterm>
       <glossdef>
        <para>
         Lorem ipsum&hellip;
        </para>
       </glossdef>
      </glossentry>
     </glosslist>
    </book>

Generating the XHTML with

    xsltproc --nonet 
/usr/share/xml/docbook/xsl-stylesheets-1.79.2-nons/xhtml/docbook.xsl test.sgml 
| grep '</a></em></a>'

gives me

    <a class="glossterm" href="#glossary-b"><em class="glossterm"><a 
class="glossterm" href="#glossary-b" title="B">B</a></em></a>

> Not sure about how to fix this (don't really know docbook).

My XSLT skills are quite rusty, but maybe it's possible to omit the
outer <a class="glossterm"> and just emit <em class="glossterm"> and its
child <a> in our stylesheets.

[1] https://github.com/docbook/xslt10-stylesheets/issues/24
[2] 
https://github.com/docbook/xslt10-stylesheets/commit/c242ce2b8c1a5ebfdb2e719f788367bb1ddee8ea

-- 
Erik