Calendar.Component.day ignores calendar month differences

[joshuakcockrell]

In Swift, this code shows a 31 day difference

let today = Date()
let future = Calendar.current.date(
  byAdding: .day,
  value: 31,
  to: today
) ?? Date()
print(Calendar.current.dateComponents([.day], from: today, to: future).day ?? 0) // ~31 days

But when transpiled through Skip it only shows a 0 or 1 day difference between the two dates.

This is because this line in DateComponents.swift incorrectly maps the .day Swift case to java.util.Calendar.DAY_OF_MONTH, which only looks at "day of month" and ignores differences between months. Jan 1 and Feb 1 are treated the same.

Here's a workaround till this is fixed.

    #if SKIP
    let startDate = startDate(nocopy: true).toInstant().atZone(ZoneId.systemDefault()).toLocalDate()
    let endDate = endDate.kotlin(nocopy: true).toInstant().atZone(ZoneId.systemDefault()).toLocalDate()
    return ChronoUnit.DAYS.between(startDate, endDate).toInt()
    #else
    return Calendar.current.dateComponents([.day], from: startDate, to: endDate).day ?? 0
    #endif