Python date string testing -

in python based application, user can enter dates in format of dd/mm/yy date separator variations(like can use /,- or space seperator). therefore these valid dates:

10/02/2009 07 22 2009 09-08-2008 9-9/2008 11/4 2010  03/07-2009 09-01 2010 

now in order test it, need create list of such dates, not sure how auto generate random combinations of these date strings seperators.

this started doing:

date = ['10', '10', '2010'] seperators = ['/', '-', ' '] s in seperators:     new_date = s.join(date) 

i think previous answers didn't much. if choose "day" number 1-31 , "month" number 1-12 in test data, productive code must raise exceptions somewhere - 02/31/2013 should not accepted!

therefore, should create random, valid dates , create strings them arbitrarily chosen format strings. code does:

import datetime import time import random  separators = ["/",",","-"," "] prefixes = [""," "]  def random_datetime(min_date, max_date):     since_epoch_min = time.mktime(min_date.timetuple())     since_epoch_max = time.mktime(max_date.timetuple())     random_time = random.randint(since_epoch_min, since_epoch_max)     return datetime.datetime.fromtimestamp(random_time)  def random_date_string_with_random_separators(dt):     prefix = random.choice(prefixes)     sep1 = random.choice(separators)     sep2 = random.choice(separators)      format_string = "{}%m{}%d{}%y".format(prefix, sep1, sep2)     return dt.strftime(format_string)    min_date = datetime.datetime(2012,01,01) max_date = datetime.datetime(2013,01,01)  in range(10):     print random_date_string_with_random_separators(                     random_datetime(min_date, max_date)           ) 

this should cover cases (if take more ten values).

nevertheless, have 2 remarks:

don't use random data test-input

you'll never know if someday test fail, maybe don't catch possible problems data generated. in case should o.k., it's not practice (if have choice). alternatively, create well-thought set of hard-coded input strings cover corner cases. , if someday tests fail, know it's no random effect.

use well-tested code

for task describe, there's library that! use dateutil. have fantastic datetime-parser swallows throw @ it. example:

from dateutil import parser  in range(10):     date_string = random_date_string_with_random_separators(                     random_datetime(min_date, max_date)           )     parsed_datetime = parser.parse(date_string)     print date_string, parsed_datetime.strftime("%m/%d/%y") 

output:

 01 05,2012 01/05/2012 05 17-2012 05/17/2012 06-07-2012 06/07/2012 10 31,2012 10/31/2012  10/04,2012 10/04/2012  11 16,2012 11/16/2012  03/23 2012 03/23/2012 02-26-2012 02/26/2012  01,12-2012 01/12/2012 12-21 2012 12/21/2012 

then can sure works. dateutilhas tons of unit tests , "just work". , best code can write code don't have test.