How can I have my custom DateTimeFormat consume a string but return a different value during parsing...

# kotlinx-datetime

[Matas Lauzadis]

How can I have my custom DateTimeFormat consume a string but return a different value during parsing?

I'm trying to add support for leap seconds (23:59:60) which needs to subtract one second (becoming 23:59:59). I have a function: private fun WithTime.secondOrleapSecond() = alternativeParsing({ second() }) { chars("60") } . This can parse the leap seconds without crashing, but (understandably) returns 23:59:0 . How can I set seconds = 59 in this case? I found a GitHub issue about leap seconds, there was a hint of a solution but none offered.

[Dmitry Khalanskiy [JB]]

Hi! There is such an example in the README file: https://github.com/Kotlin/kotlinx-datetime/?tab=readme-ov-file#parsing-and-formatting-partial-compound-or-out-of-bounds-data

[Matas Lauzadis]

Oh wow, thanks! Missed it 🤦

Works great.