formatISO omitting final Z character in dates

[aryzing]

An ISO date should have either a time offset or Z appended to the end. Omitting this Z character causes the date as being relative to the host machine's timezone. When performing operations across time zones, this is problematic.

[jpodpro]

just noticing this too. isn't the whole point of iso8601 that it must have a time-zone specified also?

[imballinst]

Hmm, back then we only took the date, time, and datetime as the scope (see http://support.sas.com/documentation/cdl/en/lrdict/64316/HTML/default/viewer.htm#a003169814.htm). We can add timezone if it is needed. WDYT @leshakoss?

I think the reason we thought that it was okay to omit timezone because ISO8601 is mostly in UTC (?)

EDIT: nvm I was silly.

[kossnocorp]

I believe the full output should contain the timezone. I didn't think about that when I was looking at the PR. Not sure how it fits the API though.

[imballinst]

I can work on this issue, this weekend. My plan is if the passed option is extended (which is the default one), we show the timezone as well.

[cyberwombat]

Perhaps along the same lines - doesn't seem possible to use format with UTC either. See this SO post https://stackoverflow.com/questions/58561169/date-fns-how-do-i-format-to-utc