While playing with the patch I noticed that to_char(..., 'RN') doesn't seem to be test-covered. I suggest adding the following test:
``` WITH rows AS ( SELECT i, to_char(i, 'FMRN') AS roman FROM generate_series(1, 3999) AS i ) SELECT bool_and(to_number(roman, 'RN') = i) FROM rows;
bool_and ---------- t ```
I also noticed there are no tests for to_char roman format. The test you provided covers roman format in both to_char and to_number. I will add it. Thank you.
