I wrote this test, but in order not to delay the test, I mock the time.sleep and the test will encounter an fail.
from unittest.mock import patch
from django.core.management import call_command
from django.db.utils import OperationalError
from django.test import TestCase
class CommandsTest(TestCase):
#patch('time.sleep', return_value=None)
def test_wait_for_db(self):
"""Test waiting for db"""
with patch('django.utils.connection.BaseConnectionHandler.__getitem__') as gi:
gi.side_effect = [OperationalError] * 5 + [True]
call_command('wait_for_db')
self.assertEqual(gi.call_count, 6)
By commenting on this second line(#patch), the program will run properly.
here is the error:
ERROR: test_wait_for_db (core.tests.test_commands.CommandsTest)
Test waiting for db
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/local/lib/python3.10/unittest/mock.py", line 1369, in patched
return func(*newargs, **newkeywargs)
TypeError: CommandsTest.test_wait_for_db() takes 1 positional argument but 2 were given
You'll need to add an argument to your test_wait_for_db.
Since you use a decorator, the mocked function is passed as argument to that function
class CommandsTest(TestCase):
#patch('time.sleep', return_value=None)
def test_wait_for_db(self, mocked_sleep):
In your test you can then test assert if indeed was called. More information here.
Related
How to disable decorator during project unittests in Python?
When running the unittests, I would like to disable the selected decorator for the duration of the tests.
import unittest
import functools
def handle_value_error(func):
#functools.wraps(func)
def wrapper_handle_value_error():
try:
return func()
except ValueError as e:
print(f"During calling {func.__name__!r} an error was raised: {str(e)}")
return wrapper_handle_value_error
#handle_value_error
def func_that_raise_value_error():
# do something
raise ValueError
def disable_decorator_for(func, decorator):
# do something that disable handle_value_error decorator
pass
class TestFunc(unittest.TestCase):
def test_func_that_raise_value_error(self):
disable_decorator_for(func=func_thar_raise_value_error, decorator=handle_value_error)
with self.assertRaises(ValueError):
func_thar_raise_value_error()
When function disable_decorator_for() is called, the tests should pass, but the output is:
During calling 'func_thar_raise_value_error' an error was raised:
Failure
Traceback (most recent call last):
File "...\disable_decorator_for_unittests.py", line 29, in test_func_thar_raise_value_error
with self.assertRaises(ValueError):
AssertionError: ValueError not raised
Ran 1 test in 0.003s
FAILED (failures=1)
Process finished with exit code 1
In a rather complex test scenario I need to mock the base class of one of my own classes and instantiate the latter several times. When I do that my test errors with a StopIteration exception. Here's what my scenario boils down to in this respect:
Code under test (my_class.py):
from oauthlib.oauth2 import BackendApplicationClient
from requests_oauthlib import OAuth2Session
class MySession(OAuth2Session):
pass
class MyClass:
def init(self, x):
self.x = x
client = BackendApplicationClient(client_id=x)
self.session = MySession(client=client)
Test code (test_mock.py):
import unittest
from unittest.mock import patch
with patch('requests_oauthlib.OAuth2Session') as MockSession:
from my_class import MyClass
cls = MyClass()
class MockTest(unittest.TestCase):
def test_mock_1(self):
cls.init(1)
self.assertIsNotNone(cls.session)
def test_mock_2(self):
cls.init(2)
self.assertIsNotNone(cls.session)
Test result:
$ python -m unittest test_mock
.E
======================================================================
ERROR: test_mock_2 (test_mock.MockTest)
----------------------------------------------------------------------
Traceback (most recent call last):
File "...\test_mock.py", line 16, in test_mock_2
cls.init(2)
File "...\my_class.py", line 11, in init
self.session = MySession(client=client)
File "C:\Python39\lib\unittest\mock.py", line 1093, in __call__
return self._mock_call(*args, **kwargs)
File "C:\Python39\lib\unittest\mock.py", line 1097, in _mock_call
return self._execute_mock_call(*args, **kwargs)
File "C:\Python39\lib\unittest\mock.py", line 1154, in _execute_mock_call
result = next(effect)
StopIteration
----------------------------------------------------------------------
Ran 2 tests in 0.003s
FAILED (errors=1)
I have debugged into the unittest.mock.MagicMock class but I can't figure out what's going on. In MagicMock's _execute_mock_call() method I noticed that self.side_effect is a tuple iterator object and when next() is called on that in the second test (test_mock_2) it results in the StopIteration.
Both tests run "OK" if I don't use the MySession subclass, i.e. self.session = OAuth2Session(client=client) in MyClass' init() method. (But that's just not how the real code under test works...)
Any ideas anyone?
You should mock class which you directly use, because your custom class inherit Mock and next starts unexpected behavior.
Rewrite path method to your custom class.
import unittest
from unittest.mock import patch
with patch('my_class.MySession') as MockSession:
from my_class import MyClass
What is wrong with my code below?
I'm expecting assert call_func_once_with("b") to throw an error as call_func was passed 'a'. I confimed that the function was indeed called once and with argument 'a'.
from unittest.mock import Mock, patch
def call_func(x):
pass
#patch("__main__.call_func")
def test_call_func(call_func):
call_func("a")
assert call_func.called_once_with("b")
assert call_func.called == 1
print(call_func.call_args)
test_call_func()
Output:
call('a')
You're not the first person to notice strange things with these types of assertions (see Magic mock assert_called_once vs assert_called_once_with weird behaviour)
For what it's worth, I can only advise that you try to create a test class which inherits from unittest.TestCase and then use the assertEqual method to get more consistent test behaviour:
import unittest
from unittest.mock import patch, call
def call_func(x):
pass
class MyTests(unittest.TestCase):
#patch("__main__.call_func")
def test_call_func(self, call_func_mock):
call_func_mock("a")
# assert call_func_mock.called == 1
# assert call_func_mock.called_once_with("b")
self.assertEqual(call_func_mock.call_count, 1)
self.assertEqual(call_func_mock.call_args_list[0], call("b"))
print(call_func_mock.call_args)
unittest.main()
This gives the following (expected) results:
F
======================================================================
FAIL: test_call_func (__main__.MyTests)
----------------------------------------------------------------------
Traceback (most recent call last):
File "C:\Python36\lib\unittest\mock.py", line 1179, in patched
return func(*args, **keywargs)
File "C:/scratch.py", line 16, in test_call_func
self.assertEquals(call_func_mock.call_args_list[0], call("b"))
AssertionError: call('a') != call('b')
----------------------------------------------------------------------
Ran 1 test in 0.003s
FAILED (failures=1)
Process finished with exit code 1
I am using HtmlTestRunner to generate my test report, but I am not able to understand why I am getting this error: "TypeError: issubclass() arg 1 must be a class"
My setup is Python 3.6, pytest, Ubuntu 17.10.
This is the code I have written:
from pages.Home.category_page import CategoryPage
from utilites.testStatus import TestStatus
import pytest
import unittest
import time
#pytest.mark.usefixture("oneTimeSetUp","setUp")
class CategoryTest(unittest.TestCase):
#pytest.fixture(autouse=True)
def classSetup(self,oneTimeSetUp):
self.ca = CategoryPage(self.driver)
self.ts = TestStatus(self.driver)
#pytest.mark.run(order=1)
def test_Announcements_link_WAF001(self):
result = self.ca.find_announcements_link()
self.ts.markFinal("Announcements link", result,"To find announcements link")
time.sleep(2)
#pytest.mark.run(order=2)
def test_FirstLinkInAnnouncements_WAF002(self):
result=self.ca.find_first_announcement_link()
self.ts.markFinal("Latest link in announcements",result,"To click on latest announcements link")
time.sleep(2)
#pytest.mark.run(order=3)
def test_Products_Link_WAF003(self):
result=self.ca.find_products()
self.ts.markFinal("Products link",result,"To find products link")
time.sleep(2)
#pytest.mark.run(order=4)
def test_FirstLinkInProducts_WAF004(self):
result=self.ca.find_first_products_link()
self.ts.markFinal("Latest link in products",result,"To click on latest products link")
time.sleep(2)
The test suite runner:
from unittest import TestLoader, TestSuite
from HtmlTestRunner import HTMLTestRunner
from tests.Home import category_test
example_tests = TestLoader().loadTestsFromTestCase(category_test)
suite = TestSuite(example_tests)
runner = HTMLTestRunner(output='example_suite', template='path/to/template', report_title='My Report')
runner.run(suite)
This is the resulting error:
Traceback (most recent call last):
File "/home/manoj/PycharmProjects/untitled8/test/test_suite.py", line 6, in <module>
example_tests = TestLoader().loadTestsFromTestCase(to_test_login)
File "/usr/lib/python3.6/unittest/loader.py", line 85, in loadTestsFromTestCase
if issubclass(testCaseClass, suite.TestSuite):
TypeError: issubclass() arg 1 must be a class
Your problem is that you are passing the test module, instead of the test class, to the runner. If you look at unittest's documentation for loadTestsFromTestCase, you'll see its argument needs to be a TestCase-derived class.
I reduced your example to a minimal version to simplify my answer a bit:
In tests.py:
import unittest
class MyTestCase(unittest.TestCase):
def test_something(self):
assert True
runner.py, based on yours:
from unittest import TestLoader, TestSuite, TextTestRunner
import tests
example_tests = TestLoader().loadTestsFromTestCase(tests)
suite = TestSuite(example_tests)
runner = TextTestRunner()
runner.run(suite)
This will give the following output:
$ python runner.py
Traceback (most recent call last):
File "runner.py", line 4, in <module>
example_tests = TestLoader().loadTestsFromTestCase(tests)
File "/usr/local/Cellar/python/3.6.5/Frameworks/Python.framework/Versions/3.6/lib/python3.6/unittest/loader.py", line 85, in loadTestsFromTestCase
if issubclass(testCaseClass, suite.TestSuite):
TypeError: issubclass() arg 1 must be a class
If I switch runner.py to use the class instead, it works:
from unittest import TestLoader, TestSuite, TextTestRunner
from tests import MyTestCase
example_tests = TestLoader().loadTestsFromTestCase(MyTestCase)
suite = TestSuite(example_tests)
runner = TextTestRunner()
runner.run(suite)
Output:
$ python runner.py
.
----------------------------------------------------------------------
Ran 1 test in 0.000s
OK
You should be able to adapt this to your code. That being said, the pytest integration might not work with HtmlTestRunner, which is unittest-based. Make sure you look into pytest-html
I am trying to write a unittest for a function named search_ldap(), which searches an LDAP server given a particular username. Here is the function definition in utils.py (note: I'm using Python 3):
from ldap3 import Server, Connection
def search_ldap(username):
result = ()
baseDN = "o=Universiteit van Tilburg,c=NL"
searchFilter = '(uid={})'.format(username)
attributes = ['givenName', 'cn', 'employeeNumber', 'mail']
try:
server = Server('ldap.example.com', use_ssl=True)
conn = Connection(server, auto_bind=True)
conn.search(baseDN, searchFilter, attributes=attributes)
for a in attributes:
result += (conn.response[0]['attributes'][a][0], )
except Exception:
raise LDAPError('Error in LDAP query')
return result
Of course I don't want to actually connect to ldap.example.com during testing, so I've decided to use Python's mock object library to mock the Server() and Connection() classes in my unittests. Here is the test code:
from unittest import mock
from django.test import TestCase
class LdapTest(TestCase):
#mock.patch('ldap3.Server')
#mock.patch('ldap3.Connection')
def test_search_ldap(self, mockConnection, mockServer):
from .utils import search_ldap
search_ldap('username')
self.assertTrue(mockServer.called)
self.assertTrue(mockConnection.called)
This test simply asserts that the mocked Server and Connection objects are instantiated. However, thay don't, because when I run the tests with ./manage.py test I receive the following error:
Creating test database for alias 'default'...
F.
======================================================================
FAIL: test_search_ldap (uvt_user.tests.LdapTest)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/lib/python3.4/unittest/mock.py", line 1142, in patched
return func(*args, **keywargs)
File "/home/jj/projects/autodidact/uvt_user/tests.py", line 28, in test_search_ldap
self.assertTrue(mockServer.called)
AssertionError: False is not true
----------------------------------------------------------------------
Ran 2 tests in 0.030s
FAILED (failures=1)
Destroying test database for alias 'default'...
Why are my tests failing? How can I successfully mock ldap3's Server and Connection classes?
To mock class you should provide it's fake implementation with required methods. For example:
class FakeServer:
def call():
pass
class LdapTest(TestCase):
#mock.patch('ldap3.Server', FakeServer)
def test_search_ldap(self):
<do you checks here>
With patch() it is important that you patch objects in the namespace where they are looked up. This is explained in the Where to patch section of the documentation. There is a fundamental difference between doing
from ldap3 import Server
server = Server()
and
import ldap3
server = ldap3.Server()
In the first case (also the case in the original question), the name "Server" belongs to the current module. In the second case, the name "Server" belongs to the ldap3 module where it is defined. The following Django unittest patches the correct "Server" and "Connection" names and should work as intended:
from unittest import mock
from django.test import TestCase
class LdapTest(TestCase):
#mock.patch('appname.utils.Server')
#mock.patch('appname.utils.Connection')
def test_search_ldap(self, mockConnection, mockServer):
from .utils import search_ldap
search_ldap('username')
self.assertTrue(mockServer.called)
self.assertTrue(mockConnection.called)