Sphinx 5 requires a valid language code

[florianernst]

Hello there,

liblognorm documentation fails to build with Sphinx 5.0:

make[4]: Entering directory '/<>/doc'
sphinx-build -b html -d _build/doctrees -n -W -c . . _build/html
Running Sphinx v5.0.2

Warning, treated as error:
Invalid configuration value found: 'language = None'. Update your configuration to a valid langauge code. Falling back to 'en' (English).
make[4]: *** [Makefile:488: html-local] Error 2

Making the language choice explicit as per the following patch allows building the documentation with both Sphinx 4.5.0 and Sphinx 5.0.2:

Index: liblognorm/doc/conf.py
===================================================================
--- liblognorm.orig/doc/conf.py
+++ liblognorm/doc/conf.py
@@ -56,7 +56,7 @@ release = '1.1.2'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
-language = None
+language = 'en'
 
 # There are two options for replacing |today|: either, you set today to some
 # non-false value, then it is used:

This was initially reported to the Debian Bug Tracking System.

Best regards,
Flo