def test_datatypes_datehelpers_weekofyear():
assert TimexDateHelpers.week_of_year(datetime(2017, 1, 1)) == 1
assert TimexDateHelpers.week_of_year(datetime(2017, 1, 2)) == 2
assert TimexDateHelpers.week_of_year(datetime(2017, 2, 23)) == 9
assert TimexDateHelpers.week_of_year(datetime(2017, 3, 15)) == 12
assert TimexDateHelpers.week_of_year(datetime(2017, 9, 25)) == 40
assert TimexDateHelpers.week_of_year(datetime(2017, 12, 31)) == 53
assert TimexDateHelpers.week_of_year(datetime(2018, 1, 1)) == 1
assert TimexDateHelpers.week_of_year(datetime(2018, 1, 2)) == 1
assert TimexDateHelpers.week_of_year(datetime(2018, 1, 7)) == 1
assert TimexDateHelpers.week_of_year(datetime(2018, 1, 8)) == 2
def test_datatypes_datehelpers_invariance():
d = datetime(2017, 8, 25)
before = d
TimexDateHelpers.tomorrow(d)
TimexDateHelpers.yesterday(d)
TimexDateHelpers.date_part_equal(datetime.now(), d)
TimexDateHelpers.date_part_equal(d, datetime.now())
TimexDateHelpers.is_next_week(d, datetime.now())
TimexDateHelpers.is_next_week(datetime.now(), d)
TimexDateHelpers.is_last_week(datetime.now(), d)
TimexDateHelpers.week_of_year(d)
after = d
assert after is before