Re: [PATCH v3 6/9] docs: pdfdocs: One-half spacing for CJK translations

From: Jonathan Corbet
Date: Thu Aug 12 2021 - 10:42:59 EST

Akira Yokosawa <akiyks@xxxxxxxxx> writes:

> On Mon, 2 Aug 2021 18:56:16 +0900, Akira Yokosawa wrote:
>> CJK documents are much easier to read with a wider baseline stretch.
>> Applying the onehalfspacing option of "setspace" package looks
>> reasonable.
>> Note: \usepackage{setspace} needs to be before that of hyperref in the
>> preamble. The 'extrapackages' key (available since Sphinx 2.3) is for
>> this purpose.
> Sphinx versions < 2.3 ignore 'extrapackages' and generate LaTeX
> sources without setspace package.
> Obviously, building such LaTeX sources will end up in the error of:
> ! Undefined control sequence.
> \kerneldocCJKoff ...exeCJKinactive \singlespacing
> Current requirement to build pdfdocs is Sphinx 2.4.4, but LaTeX
> sources generated by 1.7.9 can at least be built prior to this change.
> Jon, Mauro, do you think this is a regression?

Having the build just fail that way isn't really a good would
be far better to do the baseline tweaking only with versions of sphinx
that support it or, failing that, to at least refuse to build with a
suitably informative message.