Mock pathc question

[balderman at gmail.com]

Hi
I would like to mock patch the attribute 'calc' in the 'Client' class (See code below).
I have 2 unit tests:
1) test1 -  that patch an existing instance of 'Client' - it works fine.
1) test2 -  that tries to patch the 'Client' class. My expectation is that after the patching, every instance of 'Client' will be created with 'MockClient'. However this is not the case..

Can you please advice?

Thanks 

Avishay


code below:
-------------------------------------

import mock
import sys
import unittest

SEVEN = 7

class Calc:
    def __init__(self):
        print self.__class__
    def add(self,a,b):
        return a + b
        
class MockCalc:
    def __init__(self):
        print self.__class__
    def add(self,a,b):
        return SEVEN
        
class Client:
    def __init__(self):
        self.calc = Calc()
    def add(self,a,b):
        return self.calc.add(a,b)

class TestIt(unittest.TestCase):
    def setUp(self):
        pass    

    def test2(self):
        '''Mocking the Calc and replace it with MockCalc.'''  
        print " \ntest2 "
        my_mock = mock.patch('mock_play.Calc',create=True, new=MockCalc)
        my_mock.start()
        # client should be created with 'MockCalc'
        client = Client()
        # result should be 7
        print str(client.add(1,34))
        my_mock.stop()
        # result should be 35 again
        print str(client.add(1,34))    

    def test1(self):
        '''Mocking the client instance.'''  
        print " test1 "        
        client = Client()
        my_mock = mock.patch.object(client, 'calc', new_callable=MockCalc)
        # result should be 35
        print str(client.add(1,34))
        # now i want to switch to the MockCalc
        my_mock.start()
        # result should be 7
        print str(client.add(1,34))    
        my_mock.stop()
        # result should be 35 again
        print str(client.add(1,34))    
    
if __name__ == "__main__":
    unittest.main()