Bug#870248: pandoc: Collision for lang-Variable when using specific language for pandoc-citeproc and Babel (Latex)

[cms at dock.in-berlin.de]

Package: pandoc
Version: 1.19.2.1~dfsg+really1.19.1-1
Severity: normal

Dear Maintainer,

it seems that both Babel and pandoc-citeproc use `lang` as a variable to set the language, but they don't use the same language codes, e.g. for german: ngerman (Babel) and de-DE (pandoc-citeproc), so when using Babel and pandoc-citeproc, setting another language throws an error either from Babel or from pandoc-citeproc. This issue has been reportedly solved in the most recent versions of pandoc -- see https://github.com/jgm/pandoc-citeproc/issues/297 )

What I'm trying to do: Generate a PDF from Markdown using two separate files (markdown + yaml)

pandoc -o test.pdf --csl my.csl --bibliography mybib.bib test.md test.yaml

The lang is defined in test.yaml. If I set lang: ngerman, pandoc-citeproc throws an error because it is looking for locales-ng.xml, which doesn't exist.
If I set lang: de-DE, Babel throws an error because it doesn't know that language.


There is a workaround:

It seems, that pandoc-citeproc takes the first two letters of the lang variable and then looks for a file named locales-xx.xml, where xx are the first two letters of the lang variable, e.g. when defining lang: ngerman, pandoc-citeproc looks for locales-ng.xml.
Making a symbolic link from locales-ng.xml to locales-de-DE.xml did the trick. I haven't tried other languages, though.

Best,
Claus-Michael

-- System Information:
Debian Release: buster/sid
  APT prefers unstable
  APT policy: (990, 'unstable'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.11.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages pandoc depends on:
ii  libc6            2.24-12
ii  libffi6          3.2.1-6
ii  libgmp10         2:6.1.2+dfsg-1
ii  liblua5.1-0      5.1.5-8.1+b2
ii  libluajit-5.1-2  2.0.4+dfsg-1+b1
ii  libpcre3         2:8.39-4
ii  libyaml-0-2      0.1.7-2
ii  pandoc-data      1.19.2.1~dfsg+really1.19.1-1
ii  zlib1g           1:1.2.8.dfsg-5

pandoc recommends no packages.

Versions of packages pandoc suggests:
ii  pandoc-citeproc            0.10.4.1-2+b3
ii  texlive-latex-extra        2017.20170724-1
ii  texlive-latex-recommended  2017.20170724-1
pn  texlive-luatex             <none>
ii  texlive-xetex              2017.20170724-1
ii  wkhtmltopdf                0.12.3.2-3

-- no debconf information