How To Mock Just The Method Inside The Class

Trying to write a testcase for my class based function. This is skeleton of my class class Library(object): def get_file(self): pass def query_fun(self): p

Solution 1:

You need to take into account you mocked the whole class. You can mock individual methods too:

@mock.patch('library.library.Library.query_fun')
def test_get_response(self, mock_query_fun):
    mock_query_fun.return_value = {
        'text': 'Hi',
        'entities': 'value'
        }
    }
    response = MockBotter.get_response()
    self.assertIsNotNone(response)

Only Library.query_fun has been replaced, everything else in the class is still in place.

Simplified demo:

>>> from unittest import mock
>>> class Library(object):
...     def query_fun(self):
...         pass
...     def get_response(self):
...         return self.query_fun()
...
>>> with mock.patch('__main__.Library.query_fun') as mock_query_fun:
...     mock_query_fun.return_value = {'foo': 'bar'}
...     print(Library().get_response())
...
{'foo': 'bar'}

Solution 2:

I have used similar code below in my code, in case you want to mock the constructor too.

from unittest.mock import Mock

@mock.patch('library.library.Library')
def test_get_response(self, MockLibrary):
    mock_query_fun = Mock()
    mock_query_fun.return_value = {
        'text': 'Hi',
        'entities': 'value'
    }
    MockLibrary.return_value = Mock(
        query_fun=mock_query_fun
    )
    
    ...