LibreOffice inherited a text language guesser, based on textcat from wise-guys.nl and extended by Jocelyn Merand to basically handle UTF-8 text. This is the thing that makes the suggestions as to what language your text might really be in when you right click on some misspelled text and chose set language.
We’ve now spun this off as a standalone libexttextcat and fixed up some conversion problems from the original selection of 8bit encodings and generated new language fingerprints in other cases, which should give better results for various languages, and allow us to enable checking for some languages which was disabled until now.
The current list of languages it attempts to detect can be seen here
Here’s a plausible process to add your favourite language to it, given git clone git://anongit.freedesktop.org/libreoffice/libexttextcat and bootstrapping from the insanely-translated UDHR using Abkhaz as an example.
cd libexttextcat/langclass/ShortTexts/
wget http://unicode.org/udhr/d/udhr_abk.txt
#skip english header, name result using BCP-47
tail -n+7 udhr_abk.txt > ab.txt
cd ../LM
../../src/createfp < ../ShortTexts/ab.txt > ab.lm
echo ab.lm ab--utf8 >> ../fpdb.conf
Then update the check target in src/Makefile.am to confirm the detection of ShortTexts/ab.txt as ab works using make check
I’ll remove the necessity of a configuration file in a later version, and convert the result to a BCP-47 tag. For the moment it remains a drop in replacement for the original solution which necessitates retaining the slightly odd language tag syntax.