mock

salary.py

import requests


class ThirdPartyBonusRestApi(object):
    def get_api_name(self):
        return 'Bonus!'
    def bonus_price(self, year):
        r = requests.get('http://localhost/bonus', params={'year':year})
        return r.json()['price']


class Salary(object):
    def __init__(self, base=100, year=2017):
        self.bonus_api = ThirdPartyBonusRestApi()
        self.base = base
        self.year = year

    def get_from_boss(self):
        return 0

    def calculation_salary(self):
        bonus = 0
        if self.year < 2020:
            try:
                bonus = self.bonus_api.bonus_price(year=self.year)
            except ConnectionRefusedError:
                bonus = 0
        bonus += self.get_from_boss()
        return self.base + bonus

test_salary.py

import unittest
from unittest.mock import MagicMock
from unittest import mock
import salary


class TestSalary(unittest.TestCase):
    def test_calculation_salary(self):
        s = salary.Salary(year=2017)
        s.bonus_api.bonus_price = MagicMock(return_value=1)
        self.assertEqual(s.calculation_salary(), 101)
        s.bonus_api.bonus_price.assert_called()
        s.bonus_api.bonus_price.assert_called_once()
        s.bonus_api.bonus_price.assert_called_with(year=2017)
        s.bonus_api.bonus_price.assert_called_once_with(
            year=2017
        )
        self.assertEqual(s.bonus_api.bonus_price.call_count, 1)

    def test_calculation_salary_no_salary(self):
        s = salary.Salary(year=2050)
        s.bonus_api.bonus_price = MagicMock(return_value=0)
        self.assertEqual(s.calculation_salary(), 100)
        s.bonus_api.bonus_price.assert_not_called()

    @mock.patch('salary.ThirdPartyBonusRestApi.bonus_price', return_value=1)
    def test_calculation_salary_patch(self, mock_bonus):
        #mock_bonus.return_value = 1

        s = salary.Salary(year=2017)
        #salary_price = s.calculation_salary()
        #s.bonus_api.bonus_price = MagicMock(return_value=1)

        self.assertEqual(s.calculation_salary(), 101)
        mock_bonus.assert_called()

    def test_calculation_salary_patch_with(self):
        with mock.patch('salary.ThirdPartyBonusRestApi.bonus_price') as mock_bonus:
            mock_bonus.return_value = 1

            s = salary.Salary(year=2017)
            # salary_price = s.calculation_salary()
            # s.bonus_api.bonus_price = MagicMock(return_value=1)

            self.assertEqual(s.calculation_salary(), 101)
            mock_bonus.assert_called()

    def setUp(self):
        self.patcher = mock.patch('salary.ThirdPartyBonusRestApi.bonus_price')
        self.mock_bonus = self.patcher.start()

    def tearDown(self):
        self.patcher.stop()

    def test_calculation_salary_patch_patcher(self):
        #Not required because there is setup
        #patcher = mock.patch('salary.ThirdPartyBonusRestApi.bonus_price')
        #mock_bonus = patcher.start()
        self.mock_bonus.return_value = 1

        s = salary.Salary(year=2017)
        salary_price = s.calculation_salary()
        # s.bonus_api.bonus_price = MagicMock(return_value=1)

        self.assertEqual(salary_price, 101)
        self.mock_bonus.assert_called()
        #Not needed because there is tearDown
        #patcher.stop()

    def test_calculation_salary_patch_side_effect(self):
        #def f(year):
        #    return 1

        #self.mock_bonus.side_effect = f
        #self.mock_bonus.side_effect = lambda year: 1
        #self.mock_bonus.side_effect = ConnectionRefusedError
        self.mock_bonus.side_effect = [1,2,3,ValueError('Bankrupt!!!')]

        s = salary.Salary(year=2017)
        salary_price = s.calculation_salary()
        self.assertEqual(salary_price, 101)

        s = salary.Salary(year=2018)
        salary_price = s.calculation_salary()
        self.assertEqual(salary_price, 102)

        s = salary.Salary(year=2019)
        salary_price = s.calculation_salary()
        self.assertEqual(salary_price, 103)

        s = salary.Salary(year=200)
        with self.assertRaises(ValueError):
            s.calculation_salary()

    @mock.patch('salary.ThirdPartyBonusRestApi', spec=True)
    @mock.patch('salary.Salary.get_from_boss')
    def test_calculation_salary_class(self, mock_boss, MockRest):
        mock_boss.return_value = 10
        mock_rest = MockRest.return_value
        #mock_rest = MockRest()
        mock_rest.bonus_price.return_value = 1
        mock_rest.get_api_name.return_value = 'Money'

        s = salary.Salary(year=2017)
        salary_price = s.calculation_salary()

        self.assertEqual(salary_price, 111)
        mock_rest.bonus_price.assert_called()