When the translated text is significantly shorter (or longer) than the original text, it would make sense to issue a warning about this. For example, let's say the original text contains a whole paragraph of text, yet the translation is two words – chances are something was left out by accident.
What is a 'significant' length difference is up to debate, but as a starting point for a heuristic I propose:
- Do not warn about
msgid/msgstr pairs when both have length under 50 characters.
- In all other cases, warn if
msgid is at least 3 times longer than msgstr (or vice versa).