Fix parsing of 29.02. etc. in leap years

Just in time for 2020.

Author: geier

CHANGELOG.rst

@@ -14,6 +14,7 @@ not released yet
 * BREAKING CHANGE: python 2 is no longer supported (Hugo Osvaldo Barrera)
 * updated dependency: vdirsyncer >= 0.5.2
 * make tests work with icalendar 3.9.2 (no functional changes) (Christian Geier)
+* new dependency: freezegun (only for running the tests)
 
 * support for showing the birthday of contacts with no FN property (Hugo
   Osvaldo Barrera)

khal/aux.py

@@ -22,9 +22,11 @@
 """this module contains some helper functions converting strings or list of
 strings to date(time) or event objects"""
 
+from calendar import isleap
 from datetime import date, datetime, timedelta, time
 import random
 import string
+from time import strptime
 
 import icalendar
 import pytz
@@ -145,14 +147,18 @@ def datetimefstr_weekday(dtime_list, timeformat):
     return dtime
 
 
-def guessdatetimefstr(dtime_list, locale, default_day=datetime.today()):
+def guessdatetimefstr(dtime_list, locale, default_day=None):
     """
     :type dtime_list: list
     :type locale: dict
     :type default_day: datetime.datetime
     :rtype: datetime.datetime
     """
+    # if now() is called as default param, mocking with freezegun won't work
+    if default_day is None:
+        default_day = datetime.now().date()
     # TODO rename in guessdatetimefstrLIST or something saner altogether
+
     def timefstr_day(dtime_list, timeformat):
         if locale['timeformat'] == '%H:%M' and dtime_list[0] == '24:00':
             a_date = datetime.combine(default_day, time(0))
@@ -163,8 +169,26 @@ def timefstr_day(dtime_list, timeformat):
         return a_date
 
     def datefstr_year(dtime_list, dateformat):
-        a_date = datetimefstr(dtime_list, dateformat)
-        a_date = datetime(*(default_day.timetuple()[:1] + a_date.timetuple()[1:5]))
+        """should be used if a date(time) without year is given
+
+        we cannot use datetimefstr() here, because only time.strptime can
+        parse the 29th of Feb. if no year is given
+
+        example: dtime_list = ['17.03.', 'description']
+                 dateformat = '%d.%m.'
+        or     : dtime_list = ['17.03.', '16:00', 'description']
+                 dateformat = '%d.%m. %H:%M'
+        """
+        parts = dtformat.count(' ') + 1
+        dtstring = ' '.join(dtime_list[0:parts])
+        dtstart = strptime(dtstring, dtformat)
+        if dtstart.tm_mon == 2 and dtstart.tm_mday == 29 and not isleap(default_day.year):
+            raise ValueError
+
+        for _ in range(parts):
+            dtime_list.pop(0)
+
+        a_date = datetime(*(default_day.timetuple()[:1] + dtstart[1:5]))
         return a_date
 
     dtstart = None

setup.py

@@ -13,6 +13,10 @@
     'tzlocal>=1.0',
 ]
 
+test_requirements = [
+    'freezegun'
+]
+
 extra_requirements = {
     'proctitle': ['setproctitle'],
 }
@@ -38,6 +42,7 @@
     },
     install_requires=requirements,
     extras_require=extra_requirements,
+    tests_require=test_requirements,
     setup_requires=['setuptools_scm'],  # not needed when using packages from PyPI
     use_scm_version={'write_to': 'khal/version.py'},
     classifiers=[

tests/aux_test.py

@@ -4,9 +4,12 @@
 
 import icalendar
 import pytz
+from freezegun import freeze_time
 
 from khal.aux import construct_event, guessdatetimefstr
 from khal import aux
+from khal.exceptions import FatalError
+import pytest
 
 from .aux import _get_all_vevents_file, _get_text, \
     normalize_component
@@ -260,6 +263,30 @@ def test_construct_event_format_de_complexer():
         assert _replace_uid(event).to_ical() == vevent
 
 
+test_set_leap_year = _create_testcases(
+    ('29.02. Äwesöme Event',
+     ['BEGIN:VEVENT',
+      'SUMMARY:Äwesöme Event',
+      'DTSTART;VALUE=DATE:20160229',
+      'DTEND;VALUE=DATE:20160301',
+      'DTSTAMP;VALUE=DATE-TIME:20140216T120000Z',
+      'UID:E41JRQX2DB4P1AQZI86BAT7NHPBHPRIIHQKA',
+      'END:VEVENT']),
+)
+
+
+def test_leap_year():
+    for data_list, vevent in test_set_leap_year:
+        with freeze_time('1999-1-1'):
+            with pytest.raises(FatalError):
+                event = construct_event(
+                    data_list.split(), _now=_now, locale=locale_de)
+        with freeze_time('2016-1-1'):
+            event = construct_event(
+                data_list.split(), _now=_now, locale=locale_de)
+            assert _replace_uid(event).to_ical() == vevent
+
+
 test_set_description = _create_testcases(
     # now events where the start date has to be inferred, too
     # today