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Python test patch is never called

I am trying to test with my code by mocking the PyGithub library.
I want to create a repository for an organization. So first I need to get it and on the "Organization" returned object, I need to make another call.
It fails when trying to assert that my second method was called.
I am very new to python and I am guessing that there is a missing connection between the mocks but I cannot figure out what.
class GithubService:
def __init__(self, token: str) -> None:
self.__github__ = Github(token)
self.__token__ = token
def create_repo_extra(self, repo_name, description, organization_name, team_name):
try:
organization = self.__github__.get_organization(organization_name)
repo = organization.create_repo(name=repo_name,
description=description,
private=True,
has_issues=False,
has_wiki=False,
has_projects=False,
allow_merge_commit=False)
# do other things with the returned repo.....
return True
except GithubException as ex:
print(ex.data)
return False
Here is the test:
import unittest
from unittest.mock import patch, MagicMock, ANY
from github.Organization import Organization
from github.Repository import Repository
from src.github_service import GithubService
class TestGithubService(unittest.TestCase):
#patch('github.Organization.Organization.create_repo',
side_effect=MagicMock(return_value=Repository(ANY, {}, {}, True)))
#patch('github.MainClass.Github.get_organization',
return_value=MagicMock(return_value=Organization(ANY, {}, {}, True)))
def test_create_repo_returns_true(self, get_organization, create_repo):
sut = GithubService("token")
actual = sut.create_repo_extra('repo-name', 'description', 'organization-name', 'team-name')
get_organization.assert_called() # ok
create_repo.assert_called() # failed
self.assertTrue(actual)

Since you mock your Github.get_organization you can use the MagicMock it returns directly rather than trying to mock another layer.
In this, I patch the same Github.get_organization, but avoid giving it a side effect or return value, and therefore pass it as an arg (like you did).
Then I create a convenience mock_organization and it will be the return value of the patched Github.get_organization.
Finally, the patch is checked like you did, and through the convenience mock_organization I check the create_repo method is called as well.
class TestGithubService(unittest.TestCase):
#patch("github.MainClass.Github.get_organization")
def test_create_repo_returns_true(self, mock_get_organization):
mock_organization = MagicMock()
mock_get_organization.return_value = mock_organization
sut = GithubService("token")
actual = sut.create_repo_extra(
"repo-name", "description", "organization-name", "team-name"
)
mock_get_organization.assert_called() # ok
mock_organization.create_repo.assert_called() # ok
self.assertTrue(actual)
Without seeing more of your code I am not sure why patching Organization did not work, but this is simpler, cleaner and just as effective.

Python/Pytest: patched function inside pytest_sessionstart() is not returning the expected value

I'm trying to patch a function in Pytest's pytest_sessionstart(). I was expecting the patch function to return {'SENTRY_DSN': "WRONG"}, however. I'm getting back <MagicMoc ... id='4342393248'> object in the test run.
import pytest
from unittest.mock import patch, Mock
def pytest_sessionstart(session):
"""
:type request: _pytest.python.SubRequest
:return:
"""
mock_my_func = patch('core.my_func')
mock_my_func.return_value = {'SENTRY_DSN': "WRONG"}
mock_my_func.__enter__()
def unpatch():
mock_my_func.__exit__()

This has been correctly answered by #gold_cy, so this is just an addition: as already mentioned, you are setting return_value to the patch object, not to the mock itself. The easiest way to correct is is to use instead:
from unittest.mock import patch
def pytest_sessionstart(session):
"""
:type request: _pytest.python.SubRequest
:return:
"""
mock_my_func = patch('core.my_func', return_value = {'SENTRY_DSN': "WRONG"})
mock_my_func.start()
This sets the return value to the mock without the need to create a separate Mock object.

Issue here seems to be that you are not properly configuring the Mock object. Given the code you have shown I am going under the assumption that you are calling some function in the following way:
with foobar() as fb:
# something happens with fb here
That call evaluates to to this essentially:
foobar().__enter__()
However, in the patching that you have shown, you have made a few critical mistakes.
You have not defined the return value of __enter__.
When you initialize a Mock object, it returns a brand new Mock object, therefore when you call __enter__ at the end of your function, it is returning a brand new object, not the one you originally created.
If I understand correctly you probably want something like this:
import pytest
from unittest.mock import patch, Mock
def pytest_sessionstart(session):
"""
:type request: _pytest.python.SubRequest
:return:
"""
mock_my_func = patch('core.my_func')
mock_context = Mock()
mock_context.return_value = {'SENTRY_DSN': "WRONG"}
mock_my_func.return_value.__enter__.return_value = mock_context
# this now returns `mock_context`
mock_my_func().__enter__()
Now mock_my_func().__enter__() returns mock_context which we can see works as expected when we do the following:
with mock_my_func() as mf:
print(mf())
>> {'SENTRY_DSN': 'WRONG'}

Python mock patch doesn't work as expected for public method

I'm trying to patch a public method for my flask application but it doesn't seem to work.
Here's my code in mrss.feed_burner
def get_feed(env=os.environ):
return 'something'
And this is how I use it
#app.route("/feed")
def feed():
mrss_feed = get_feed(env=os.environ)
response = make_response(mrss_feed)
response.headers["Content-Type"] = "application/xml"
return response
And this is my test which it's not parsing.
def test_feed(self):
with patch('mrss.feed_burner.get_feed', new=lambda: '<xml></xml>'):
response = self.app.get('/feed')
self.assertEquals('<xml></xml>', response.data)

I believe your problem is that you're not patching in the right namespace. See where_to_patch documentation for unittest.mock.patch.
Essentially, you're patching the definition of get_feed() in mrss.feed_burner but your view handler feed() already has a reference to the original mrss.feed_burner.get_feed(). To solve this problem, you need to patch the reference in your view file.
Based on your usage of get_feed in your view function, I assume you're importing get_feed like so
view_file.py
from mrss.feed_burner import get_feed
If so, you should be patching view_file.get_feed like so:
def test_feed(self):
with patch('view_file.get_feed', new=lambda: '<xml></xml>'):
...

How do modules work in Python?

I was wondering how does a module really work in Python.For example I have this code
import requests
r = requests.get("http://www.google.com")
print r.status_code
Now according to my understanding, the requests module should have a python file which would be containing a class called "get" and within the "get" class there must be a member variable called "status_code"
So when I create the object "r", I get the variable status_code for it.
However, when I looked at all the files that come in the package, I could not find any class named "get".
I could however find a function called "get", under a class called "response". But since we did not create the object as an instance of the "response" class, how can we access the "get" function inside it?
I think I am missing a key concept here, can someone point it out for me please?
Thanks

When you import requests file __init__.pyis executed, if you examine that file in your case, you will find this line:
from .api import request, get, head, post, patch, put, delete, options
Which means that from api.py you are importing get() function:
def get(url, **kwargs):
kwargs.setdefault('allow_redirects', True)
return request('get', url, **kwargs)
And as you can see it calls request function from api.py that looks like:
def request(method, url, **kwargs):
session = sessions.Session()
return session.request(method=method, url=url, **kwargs)
That creates an object Session defined inside session.py, then calls its method request. This method will call method send() which returns a Responseobject which is defined in the class Response inside models.py (I copy the first lines):
class Response(object):
def __init__(self):
super(Response, self).__init__()
self._content = False
self._content_consumed = False
#: Integer Code of responded HTTP Status.
self.status_code = None
...
Here is where status_code is defined, so when you invoke r = requests.get("http://www.google.com") you are retrieving this object and then you can access to status_code

Your understanding is not entirely correct.
The requests module is an object; .get is then an attribute lookup on that object; it has to be a callable object because you try to call it with the (...) syntax. That means it can be a class, or a function or any other object with a __call__ method.
That callable returns something; all callables do. For a class, generally an instance is returned, but for a function that can be any Python object. Whatever .get() does, it returns an object that has a .status_code attribute, or has a .__getattr__ method that returns something when called with the name status_code.
In this specific case, get() is a function, which has been imported into the requests/__init__.py package initializer module. This function, indirectly, creates a Session() instance, and calls the .request() method on that instance. That method, eventually, returns a Response instance, which does have a .status_code attribute.

When to use __getattr__

I came across the __getattr__ built-in and was wondering when it would be used. I had a hard time thinking of a practical use from the documentation
http://docs.python.org/reference/datamodel.html#. What would be an actual example of how it could be used and useful in code?

One example is to use object notation with dictionaries. For example, consider a dictionary
myDict = {'value': 1}
Typically in Python one accesses the 'value' variable as
myDict['value']
which will print 1 at the Python interpreter. However, one may wish to use the myDict.value notation. This may be achieved by using the following class:
class DictAsMember(dict):
def __getattr__(self, name):
value = self[name]
if isinstance(value, dict):
value = DictAsMember(value)
return value
my_dict = DictAsMember()
my_dict['property'] = {'sub_property': 1}
print(my_dict.property.sub_property) # 1 will be printed

An example usage would be to create a simple wrapper around some object. In order, for example, to log the calls, or modify its behavior without inheriting from it, and without having to implement the whole interface of the object.
There is several good documented examples out there, like, for example, http://western-skies.blogspot.fr/2008/02/complete-example-of-getattr-in-python.html.

Since __getattr__ is only called when an attribute is not found, it can be a useful way to define an alternate place to look up an attribute, or to give default values, similar to a defaultdict.
You could also emulate a base class higher than all the others in an object's MRO, by delegating all the lookups here to another object (though doing this you could potentially have an infinite loop if the other object is delegating the attribute back).
There is also __getattribute__, which is related in that it is called anytime any attribute is looked up on the object.

Edit: This is about the built-in function getattr, not the __getattr__ method.
I needed to do this for a REST client using bearer tokens. I wrapped Requests's Session object into my own interface so I could always send the auth header, and (more relevantly) make HTTP requests to the same site, just using the URL's path.
class RequestsWrapper():
def __init__(self, base_url):
self.client = requests.Session(
headers={'Authorization':'myauthtoken'}
)
self.base_url = base_url
def _make_path_request(self, http_method, path, **kwargs):
"""
Use the http_method string to find the requests.Session instance's
method.
"""
method_to_call = getattr(self.client, http_method.lower())
return method_to_call(self.base_url + path, **kwargs)
def path_get(self, path, **kwargs):
"""
Sends a GET request to base_url + path.
"""
return self._make_path_request('get', path, **kwargs)
def path_post(self, path, **kwargs):
"""
Sends a POST request to base_url + path.
"""
return self._make_path_request('post', path, **kwargs)
def path_put(self, path, **kwargs):
"""
Sends a PUT request to base_url + path.
"""
return self._make_path_request('put', path, **kwargs)
def path_delete(self, path, **kwargs):
"""
Sends a DELETE request to base_url + path.
"""
return self._make_path_request('delete', path, **kwargs)
Then, I could just make a request based on the path:
# Initialize
myclient = RequestsWrapper("http://www.example.com")
# Make a get request to http://www.example.com/api/spam/eggs
response = myclient.path_get("/api/spam/eggs")
# Print the response JSON data
if response.ok:
print response.json