LearnToCode Calendar tests

calendar.py

class Calendar:
    def __init__(self, day=1, month=8, year=2021):
        self.is_daytime = True
        self.day = day
        self.month = month
        self.year = year

        self.month_names = ['', 'January', 'February', 'March', 'April', 'May', 'June', 'July',
                            'August', 'September', 'October', 'November', 'December']
        self.days_count = [0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

    def next(self):
        self.day += 1
        if self.day > self.days_count[self.month]:
            self.day = 1  # first day of new month
            self.month += 1  # new month
            if self.month > 12:
                self.month = 1  # back to January
                self.year += 1  # increment year

    def next_week(self):
        self.day += 7
        if self.day > self.days_count[self.month]:
            self.day = self.day - self.days_count[self.month]
            self.month += 1  # new month
            if self.month > 12:
                self.month = 1  # back to January
                self.year += 1  # increment year

    def next_month(self):
        self.month += 1
        if self.month > 12:
            self.month = 1  # back to January
            self.year += 1  # increment year

    def get_month_string(self):
        return self.month_names[self.month]

    def get_day_string(self):
        return str(self.day)

test_calendar.py

from unittest import TestCase
from calendar import Calendar
from datetime import datetime, timedelta


class TestCalendar(TestCase):
    def test_next_month(self):
        calendar = Calendar()
        calendar.next_week()
        defaultDate = datetime(year=2021, month=8, day=1)
        weekLaterDefault = defaultDate + timedelta(days=7)
        assert calendar.day == weekLaterDefault.day

    def test_next_month_end(self):
        calendar = Calendar(year=2021, month=10, day=25)
        calendar.next_week()
        defaultDate = datetime(year=2021, month=10, day=25)
        weekLaterDefault = defaultDate + timedelta(days=7)
        assert calendar.day == weekLaterDefault.day