strptime and time zones

[jesse99]

strptime is not handling time zones correctly. For example, if you use the format string "%FT%T%z" with ISO 8601 strings like
1999-05-31T13:20:00-04:00
and
1999-05-31T13:20:00-05:00
you get identical results back.

The code on line 510 seems seems to match the time zone offset but it only does something when the offset if zero.

[yichoi]

currently %z accepts like 0400 not like 04:00, however strptime still has same problem

strptime("1999-05-31T13:20:00-0500", "%FT%T%z")
-> Ok({tm_sec: 0, tm_min: 20, tm_hour: 13, tm_mday: 31, tm_mon: 4, tm_year: 99, tm_wday: 0, tm_yday: 0, tm_isdst: 0, tm_gmtoff: 0, tm_zone: ~"", tm_nsec: 0})

strptime("1999-05-31T13:20:00-0400", "%FT%T%z")
-> Ok({tm_sec: 0, tm_min: 20, tm_hour: 13, tm_mday: 31, tm_mon: 4, tm_year: 99, tm_wday: 0, tm_yday: 0, tm_isdst: 0, tm_gmtoff: 0, tm_zone: ~"", tm_nsec: 0})

[bblum]

this looks more like feature-complete than bwds-compat; renominating

[graydon]

just a bug, removing milestone/nomination.

Filed in the time repo under time-rs/time#20. Closing.