An error occurs in epoch_to_timestamp: multiply with overflow.

[yjhong79]

The epoch_to_timestamp function can handle time units from seconds to nanoseconds.

As explained in the documentation below, the range for nanoseconds is between 1677-09-21T00:12:43.145224192 and 2262-04-11T23:47:16.854775807: https://docs.rs/chrono/latest/chrono/struct.DateTime.html#method.timestamp_nanos_opt

Inside the function, all values are forcibly converted to nanoseconds for processing. If a value is input that cannot be converted to nanoseconds (i.e., the computed value exceeds the i64 range), a multiply with overflow error occurs in debug mode. In release mode, this error is ignored, leading to incorrect calculations due to overflow.

Therefore, it seems necessary to handle inputs differently depending on their scale.

Below is test code to reproduce the error:

let overflow_time = DateTime::parse_from_rfc3339("1600-06-18T23:12:44.000Z").unwrap();
let time = epoch_to_timestamp::<1_000_000>(overflow_time.timestamp_micros());
println!("{:?}", time);  

// Release output:
// Timestamp { year: 1715, month: 11, day: 28, hour: 23, minute: 38, second: 10, fraction: 290448384 }

[pacman82]

Hello @yjhong79 ,

thanks for reporting the bug!

Yeah indeed, I think you are correct. Luckily so far no one seems to work in a domain which requires dating historical artifacts with nanoseconds precision 😁 .

I'll handle it, but I am pretty swamped until the end of the month.

Best, Markus