Mocking Functions Using Python Mock

The general case would be to use patch from mock. Consider the following:

utils.py

def get_content():
    return 'stuff'

mymodule.py

from util import get_content


class MyClass(object):

    def func(self):
        return get_content()

test.py

import unittest

from mock import patch

from mymodule import MyClass

class Test(unittest.TestCase):

    @patch('mymodule.get_content')
    def test_func(self, get_content_mock):
        get_content_mock.return_value="mocked stuff"

        my_class = MyClass()
        self.assertEqual(my_class.func(), 'mocked stuff')
        self.assertEqual(get_content_mock.call_count, 1)
        get_content_mock.assert_called_once()

Note how get_content is mocked, it is not util.get_content, rather mymodule.get_content since we are using it in mymodule.

Above has been tested with mock v2.0.0, nosetests v1.3.7 and python v2.7.9.

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