i18n utilities - crnormand/gurps GitHub Wiki
Run ./dev-utilities/json-key-diff-repair.js <lang-file.>json to get a list of keys in <lang-file>.json that are missing in en.json (probably an unused key), keys that are in en.json but not in <lang-file>.json (missing keys that probably need to be copied into <lang-file>.json) and values that are the same in both files (probably not translated).
If you run this with the fix flag, it will edit <lang-file>.json to match en.json. New keys will have the english text and must be translated. (Example: ./dev-utilities/json-key-diff-repair.js ./lang/ru.json fix.)
Example output:
gurps % ./dev-utilities/json-key-diff-repair.js ./lang/ru.json
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keys in [./lang/ru.json] that are missing in [./lang/en.json]
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keys in [./lang/en.json] that are missing in [./lang/ru.json]
GURPS.settingHintPortraitHPTinting
GURPS.settingPortraitHPTinting
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values in [./lang/en.json] that are the same in [./lang/ru.json]
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