Safe formatting of translatable strings

[askhl]

Subject: Safe formatting of translatable strings

Feature or Bugfix

• Bugfix

Purpose

There are 100+ languages, which is enough for Murphy's law to take effect if anything is imperfect.

The error recently fixed for Spanish (#8943) similarly exists in Hungarian and Greek.

Rather than fixing them individually (and have them come back in new translations), this fix changes the strings so the error cannot occur again. This of course invalidates the translations. Let me know if I should attempt to adapt the translations as well, but state of the art i18n wisdom is that it's best left to translators.

(I specify 3.5.x as target branch, but if merged, this should probably be merged/cherrypicked to master etc. as well.)

Detail

Current faulty translations:

askhl@erlkoenig:~/src/sphinx/sphinx/locale$ gtgrep --msgid '%%\(target\)' */*/*.po  --imsgstr '%%\(target\)' --msgstr . -n
el/LC_MESSAGES/sphinx.po:3303
#: sphinx/transforms/post_transforms/__init__.py:171
#, python-format
msgid "%s:%s reference target not found: %%(target)s"
msgstr "Ο %s:%s στόχος αναφοράς δεν βρέθηκε: %% (στόχος)"

el/LC_MESSAGES/sphinx.po:3308
#: sphinx/transforms/post_transforms/__init__.py:174
#, python-format
msgid "%r reference target not found: %%(target)s"
msgstr "ο στόχος αναφοράς %r δεν βρέθηκε: %%(στόχος)"

hr/LC_MESSAGES/sphinx.po:3307
#: sphinx/transforms/post_transforms/__init__.py:174
#, python-format
msgid "%r reference target not found: %%(target)s"
msgstr "%r referenca target nije pronađena: %% (target)"

Relates

#8943

[tk0miya]

Thank you for your proposal. Merged into master branch.