Re: [PATCH v2] Documentation: fix build with Asciidoctor 2

> On Fri, Sep 13, 2019 at 01:52:40AM +0000, brian m. carlson wrote:
>
>> We also need to teach xmlto how to use the namespaced DocBook XSLT
>> stylesheets instead of the non-namespaced ones it usually uses.
>> Normally these stylesheets are interchangeable, but the non-namespaced
>> ones have a bug that causes them not to strip whitespace automatically
>> from certain elements when namespaces are in use.  This results in
>> additional whitespace at the beginning of list elements, which is
>> jarring and unsightly.
>
> Thanks, this fixed most of the rendering problems I saw from the earlier
> patch.
>
>> We can do this by passing a custom stylesheet with the -x option that
>> simply imports the namespaced stylesheets via a URL.  Any system with
>> support for XML catalogs will automatically look this URL up and
>> reference a local copy instead without us having to know where this
>> local copy is located.  We know that anyone using xmlto will already
>> have catalogs set up properly since the DocBook 4.5 DTD used during
>> validation is also looked up via catalogs.  All major Linux
>> distributions distribute the necessary stylesheets and have built-in
>> catalog support, and Homebrew does as well, albeit with a requirement to
>> set an environment variable to enable catalog support.
>
> This did give me one minor hiccup: I had the debian docbook-xsl package
> installed, but not docbook-xsl-ns. The error message was pretty standard
> for XML: obvious if you know what catalogs are, and utterly confusing
> otherwise. :)
>
> Everything worked fine after installing docbook-xsl-ns. I wonder if
> could/should provide some guidance somewhere (maybe in INSTALL, which
> discusses some catalog issues?).
>
>> Finally, we need to filter out some messages from other stylesheets that
>> when invoking dblatex in the CI job.  This tool strips namespaces much
>
> s/that/that occur/ or something?
>
>> like the unnamespaced DocBook stylesheets and prints similar messages.
>> If we permit these messages to be printed to standard error, our
>> documentation CI job will because we check standard error for unexpected
>
> s/will/will fail/?
>
>> ---
>>  Documentation/Makefile    | 4 +++-
>>  Documentation/manpage.xsl | 3 +++
>>  ci/test-documentation.sh  | 2 ++
>>  3 files changed, 8 insertions(+), 1 deletion(-)
>>  create mode 100644 Documentation/manpage.xsl
>
> Running with this patch on asciidoctor 2.0.10, plus Martin's recent
> literal-block cleanups, plus his refmiscinfo fix, I get pretty decent
> output from:
>
>   ./doc-diff --from-asciidoc --to-asciidoctor origin HEAD
>
> The header/footer are still a little funny (but I think Martin said that
> he needs to update the refmiscinfo patches for later versions of
> asciidoctor, which is probably what's going on here):
> ...
> So overall, I think we're getting very close to parity.