Re: [PATCH v3 5/6] meson: prefer 'sphinx-build' to 'sphinx-build-3'

[Markus Armbruster <armbru@redhat.com>]

John Snow <jsnow@redhat.com> writes:

> On Tue, Feb 21, 2023, 1:50 AM Markus Armbruster <armbru@redhat.com> wrote:
>
>> John Snow <jsnow@redhat.com> writes:
>>
>> > Once upon a time, "sphinx-build" on certain RPM platforms invoked
>> > specifically a Python 2.x version, while "sphinx-build-3" was a distro
>> > shim for the Python 3.x version.
>> >
>> > These days, none of our supported platforms utilize a 2.x version, so it
>> > should be safe to search for 'sphinx-build' prior to 'sphinx-build-3',
>> > which will prefer pip/venv installed versions of sphinx if they're
>> > available.
>> >
>> > This adds an extremely convenient ability to test document building
>> > ability in QEMU across multiple versions of Sphinx for the purposes of
>> > compatibility testing.
>> >
>> > Signed-off-by: John Snow <jsnow@redhat.com>
>> > ---
>> >  docs/meson.build | 2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> >
>> > diff --git a/docs/meson.build b/docs/meson.build
>> > index 9136fed3b73..906034f9a87 100644
>> > --- a/docs/meson.build
>> > +++ b/docs/meson.build
>> > @@ -1,5 +1,5 @@
>> >  if get_option('sphinx_build') == ''
>> > -  sphinx_build = find_program(['sphinx-build-3', 'sphinx-build'],
>> > +  sphinx_build = find_program(['sphinx-build', 'sphinx-build-3'],
>> >                                required: get_option('docs'))
>> >  else
>> >    sphinx_build = find_program(get_option('sphinx_build'),
>>
>> Do we still need to check for sphinx-build-3?  Or asked differently, is
>> there any supported build host that provides only sphinx-build-3?
>>
>
> Yes, modern Fedora still uses "sphinx-build-3" as the name in /usr/bin for
> the rpm-packaged version of sphinx.

For what it's worth, python3-sphinx-5.0.2-2.fc37.noarch provides

    /usr/bin/sphinx-build
    /usr/bin/sphinx-build-3
    /usr/bin/sphinx-build-3.11

where the latter two are symbolic links to the first.  No need to check
for sphinx-build-3 here.

> It's just that the only platforms where "sphinx-build" is the 2.x version
> are platforms on which we want to drop 3.6 support anyway, so it's OK to
> invert the search priority in the context of this series.
>
> (All pip/pypi versions use "sphinx-build" as the binary name. In effect,
> this patch means we prefer pip/pypi versions if they're in your $PATH.)