mocking_master_part1 // python2.7.x 에서 mock.patch를 사용해서 테스트를 유연하게 진행시키는 부분입니다.

main.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import os
from os import urandom
import mock
import unittest
import pytest

from fots import abc_urandom


def simple_urandom(length):
    return 'f' * length


"""
The side_effect keyword argument simply allows you to
replace an entire function with another. Please also notice that the decorator
now adds an additional argument to the function that it wraps which
I’ve called urandom_function.
We’ll discuss some of the things you can do with this later on.
The code above also works if we were importing a
function that used os.urandom too.
"""


class TestRandomPartOne(unittest.TestCase):
    # 이런식으로 사이드 이팩트로 가져온다는것은
    # 함수를 위에 있는 것으로 가져오겠다는 뜻 입니다^^
    @mock.patch('os.urandom', side_effect=simple_urandom)
    def test_urandom(self, urandom_function):
        assert os.urandom(5) == 'fffff'


"""
OK, but what if we imported the urandom function using a from statement?
Well this is a special case where you can use __main__ to mock the function:
"""


class TestRandomPartTwo(unittest.TestCase):
    @pytest.mark.skip(reason="skip it for a moment")
    @mock.patch('__main__.urandom', side_effect=simple_urandom)
    def test_urandom(self, urandom_function):
        assert os.urandom(5) == 'fffff'


"""
At this point, we know how to mock the various
types of function calls that may occur.
If you would like to perform a much simpler mock and just replace the return
value of the function with a simple expression, you may do this:
"""


# 이런식으로도 가능합니다.
class TestRandomPartThree(unittest.TestCase):
    @mock.patch('fots.urandom', side_effect=simple_urandom)
    def test_abc_urandom(self, abc_urandom_function):
        assert abc_urandom(5) == 'abcfffff'


"""
If you would like to perform a much simpler mock and just replace
the return value of the function with a simple expression, you may do this:
"""


class TestRandomPartFour(unittest.TestCase):
    # 그러니까 urandom 이라는 모듈은 무조건  HelloWOrldHolaHola를
    # 리턴한다. fots urandom 이란애는 그 값을 리턴한다.
    # 파라미터 오타 정말 조심해야한다. 예를 들어서
    # return_value ( o )  / return_values ( x )
    @mock.patch('fots.urandom', return_value='HelloWorldHolaHola')
    def test_abc_urandom(self, abc_urandom_function):
        # abc_urandom 쪽에서는 abcHelloWorld 가 나옵니다.
        assert abc_urandom(5) == 'HelloWorld'