Smalyshev added a comment. So I think we should adopt the following approach for getting from Wikidata datetime to ISO/XSD datetime:
1. If date is Gregorian and positive - check it for ISO format breakage (0 day/month, 31 February, etc.), fix it by replacing 0 with 1 and overflowing day/month with largest allowed value. Year 0 is treated as broken data and aborts conversion. 2. If date is Gregorian and negative, do the above and then if the precision is year or higher, then for XSD 1.1 mode add 1 to the year (i.e. move the year 1 closer towards zero). 3. If the date is Julian, check the precision. If the precision is month or lower, treat the date as Gregorian above. 4. If the precision is day or higher, do the cleanups as in (1) and then convert the date to Gregorian. If converstion fails, this is bad data. Then process the negative years as described in (2). This should give an expected result on most data, and should not do anything weird except in weird cases - like day-precision date with 10 billion years ago (which makes no sense). TASK DETAIL https://phabricator.wikimedia.org/T99795 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: Smalyshev Cc: Liuxinyu970226, Jc3s5h, Smalyshev, Aklapper, daniel, jkroll, Wikidata-bugs, Jdouglas, aude, Manybubbles, JanZerebecki, Malyacko, P.Copp _______________________________________________ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
