I'm trying to check if a date is exactly one year apart, to the second - I wanted to include leap years, so I consulted the docs and found this:
However, I tried selecting the same exact date from a date picker but one in 2024 and one in 2025, and I would get a value of > 0. So I decided to check each part of the date so that I can capture the case where the dates are exactly one year apart, to the second.
Here is what that looks like in the script console (don't judge):
the code
startDate = system.date.parse('2024-01-01 00:00:00', 'YYYY-MM-dd HH:mm:ss')
endDate = system.date.parse('2025-01-01 00:00:00', 'YYYY-MM-dd HH:mm:ss')
print system.date.yearsBetween(startDate, endDate)
print system.date.getSecond(startDate) == system.date.getSecond(endDate)
print system.date.getMinute(startDate) == system.date.getMinute(endDate)
print system.date.getHour24(startDate) == system.date.getHour24(endDate)
print 'about to print dayOfMonth...'
print system.date.getDayOfMonth(startDate)
print system.date.getDayOfMonth(endDate)
print 'just printed dayOfMonth'
print system.date.getMonth(startDate) == system.date.getMonth(endDate)
print system.date.yearsBetween(startDate, endDate) == 0
Why do I get unexpected results for getDayOfMonth, when they both should be 1 - at least that's what it looks like it should be on the surface. If that's the expected behavior, why?
Time to play 'spot the difference':
startDate = system.date.parse('2024-01-01 00:00:00', 'yyyy-MM-dd HH:mm:ss')
endDate = system.date.parse('2025-01-01 00:00:00', 'yyyy-MM-dd HH:mm:ss')
print system.date.yearsBetween(startDate, endDate)
print system.date.getSecond(startDate) == system.date.getSecond(endDate)
print system.date.getMinute(startDate) == system.date.getMinute(endDate)
print system.date.getHour24(startDate) == system.date.getHour24(endDate)
print 'about to print dayOfMonth...'
print system.date.getDayOfMonth(startDate)
print system.date.getDayOfMonth(endDate)
print 'just printed dayOfMonth'
print system.date.getMonth(startDate) == system.date.getMonth(endDate)
print system.date.yearsBetween(startDate, endDate) == 0
YYYY in system.date.parse gives you the 'ISO week year', not the expected calendar year - yyyy is what you actually want.
3 Likes
I was just about to comment that the format string was breaking this...
startDate = system.date.parse('2024-01-01 00:00:00')
endDate = system.date.parse('2025-01-01 00:00:00')
print system.date.yearsBetween(startDate, endDate)
print system.date.getSecond(startDate) == system.date.getSecond(endDate)
print system.date.getMinute(startDate) == system.date.getMinute(endDate)
print system.date.getHour24(startDate) == system.date.getHour24(endDate)
print 'about to print dayOfMonth...'
print startDate
print endDate
print system.date.getDayOfMonth(startDate)
print system.date.getDayOfMonth(endDate)
print 'just printed dayOfMonth'
print system.date.getMonth(startDate) == system.date.getMonth(endDate)
print system.date.yearsBetween(startDate, endDate) == 0
1 Like
I can't believe I missed something so silly 
Thank you for the quick response!
The reason I was testing that monstrosity was because I'm trying to limit a user to only 1 year's worth of data BUT when I select Feb 1, 2024 12:00 AM and Feb 1, 2025 12:00 AM, I get system.date.yearsBetween() = 1, which is okay, but then I don't know if its exactly one year to the second, or 1 year 11 months, etc.
What would be the best way to check if two dates are at most exactly one year apart, taking into account leap years?
Datetime math is complicated.
ChatGPT suggested something like this, after some prodding:
def isAtMostOneYearApart(date1, date2):
# Ensure date1 is the earlier date
if date1.after(date2):
date1, date2 = date2, date1
# Get the number of whole years apart
years_diff = system.date.yearsBetween(date1, date2)
# If within the same year, return True
if years_diff == 0:
return True
# If exactly one year apart, check if the days difference is within a year span
if years_diff == 1:
return system.date.daysBetween(date1, date2) <= 366 # Account for leap years
return False
The general approach I think makes sense - first, check if they're within a year - easy. If they're a year apart, check if adding a year's worth of days to one gives you the same date as the other.
There's possibly a more elegant way to do this with the java.time API, but we don't have any nice helpers for that library, so it would end up pretty awkward to use.
1 Like
Given t0 and t1:
Use t1x = system.date.addYears(t0, 1) with the earlier endpoint. Check t1.time == t1x.time.
That will check for exactly a year apart, to the millisecond. Use integer divide by 1000 to ignore millis.
.addYears() handles leap years.
2 Likes
