Re: Is there an undocumented Syntax Check in Meson?

Hi,

On 2024-05-09 20:53:27 +0100, Dagfinn Ilmari Mannsåker wrote:
> Andres Freund <andres(at)anarazel(dot)de> writes:
> > On 2024-05-09 20:12:38 +0100, Dagfinn Ilmari Mannsåker wrote:
> >> Attached is a patch which adds a check-docs target for meson, which
> >> takes 0.3s on my laptop.
> >> +checkdocs = custom_target('check-docs',
> >> + input: 'postgres.sgml',
> >> + output: 'check-docs',
> >> + depfile: 'postgres-full.xml.d',
> >> + command: [xmllint, '--nonet', '--valid', '--noout',
> >> + '--path', '@OUTDIR@', '@INPUT@'],
> >> + depends: doc_generated,
> >> + build_by_default: false,
> >> +)
> >> +alias_target('check-docs', checkdocs)
> >
> > Isn't the custom target redundant with postgres_full_xml? I.e. you could just
> > have the alias_target depend on postgres_full_xml?
>
> We could, but that would actually rebuild postgres-full.xml, not just
> check the syntax (but that only takes 0.1-0.2s longer),

I don't think this is performance critical enough to worry about 0.1s. If
anything I think the performance argument goes the other way round - doing the
validation work multiple times is a waste of time...

> and only run if the docs have been modified since it was last built (which I
> guess is fine, since if you haven't modified the docs you can't have
> introduced any syntax errors).

That actually seems good to me.

> It's already possible to run that target directly, i.e.
>
> ninja doc/src/sgml/postgres-full.xml
>
> We could just document that in the list of meson doc targets, but a
> shortcut alias would roll off the fingers more easily and be more
> discoverable.

Agreed.

Greetings,

Andres Freund