days between two dates | Python Fiddle

# Credit goes to Websten from forums
#
# Use Dave's suggestions to finish your daysBetweenDates
# procedure. It will need to take into account leap years
# in addition to the correct number of days in each month.

def is_leap_year(year):
    if year%4 != 0:
        return False
    elif year%100 != 0:
        return True
    elif year%400 != 0:
        return False
    else:
        return True
    
def days_in_month(month, year):
    month_lengths = [0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 31, 31]
    return 29 if month == 2 and is_leap_year(year) else month_lengths[month]

def nextDay(year, month, day):
    day = day + 1 if day < days_in_month(month, year) else 1

if day == 1:
        if month == 12:
            month = 1
        else:
            month = month + 1
    
    year = year + 1 if month == 1 and day == 1 else year
    return (year, month, day)
        
def daysBetweenDates(year1, month1, day1, year2, month2, day2):
    """Returns the number of days between year1/month1/day1
       and year2/month2/day2. Assumes inputs are valid dates
       in Gregorian calendar, and the first date is not after
       the second."""
        
    # YOUR CODE HERE!
    days = 0
    tempYear = year1
    tempMonth = month1
    tempDay = day1
    while (tempYear, tempMonth, tempDay) != (year2, month2, day2):
        (tempYear, tempMonth, tempDay) = nextDay(tempYear, tempMonth, tempDay)
        days = days + 1
    return days

def test():
    test_cases = [
                  ((2012,2,1,2012,2,1), 0), 
                  ((2012,2,1,2012,2,2), 1), 
                  ((2012,2,1,2012,2,28), 27), 
                  ((2012,2,1,2012,2,29), 28), 
                  ((2012,2,1,2012,3,1), 29), 
                  ((2011,2,1,2011,2,1), 0), 
                  ((2011,2,1,2011,2,2), 1), 
                  ((2011,2,1,2011,2,28), 27), 
                  ((2011,2,1,2011,3,1), 28), 
                  ]
    
    for (args, answer) in test_cases:
        result = daysBetweenDates(*args)
        if result != answer:
            print "Test with data:", args, "failed"
        else:
            print "Test case passed!"

test()

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