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Creating a Unit testcase Class within a function not running testcases

I need to create a unit test class with a function so i can call the function when some event is triggered. I am using the below method but testcases are not executing
gp = r"somefile"
def MyFunc():
if os.path.exists(gp):
print("yes")
class First__Test_Cases(unittest.TestCase):
def test_001(self):
print("1")
def test__002(self):
print("2")
if __name__ == '__main__':
unittest.main()
First__Test_Cases()
else:
print("fail")
MyFunc()
output - Ran 0 tests in 0.000s

Remove MyFunc() and global parts, it should only contain class and main
mytestfile.py
import unittest
class First_Test_Cases(unittest.TestCase):
def test_001(self):
Pass
def test__002(self):
Pass
if __name__ == '__main__':
unittest.main()
Then run
python mytestfile.py
And all tests in the class will be executed:
...
----------------------------------------------------------------------
Ran 2 tests in 0.000s
OK
You can read more and see more examples in the documentation
If you need to have a function call the test, you should do that in a separate file. Check this post: Run unittests from a different file

According to what I understood from your change in code, this is your use case:
Tests should be run only if a certain file exists. Otherwise, they should be skipped.
For this use case, I would suggest the following solution:
import os
import unittest
gp = "some_file.txt"
msg = "file {} does not exist".format(gp)
class First_Test_Cases(unittest.TestCase):
#unittest.skipUnless(os.path.exists(gp), msg)
def test_001(self):
pass
#unittest.skipUnless(os.path.exists(gp), msg)
def test_002(self):
pass
if __name__ == '__main__':
unittest.main()
The output would be the following if the file does not exist:
ss
----------------------------------------------------------------------
Ran 2 tests in 0.000s
OK (skipped=2)
and this one, if it exists:
..
----------------------------------------------------------------------
Ran 2 tests in 0.000s
OK
In case if you want your tests to fail, just change the code in this way:
import os
import unittest
gp = "some_file.txt"
msg = "file {} does not exist".format(gp)
class First_Test_Cases(unittest.TestCase):
def test_001(self):
self.assertTrue(os.path.exists(gp), msg) # add this line
# your code
def test_002(self):
self.assertTrue(os.path.exists(gp), msg) # add this line
# your code
Then, the output would be the following:
FF
======================================================================
FAIL: test_001 (__main__.First_Test_Cases)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/tmp/test.py", line 11, in test_001
self.assertTrue(os.path.exists(gp), msg)
AssertionError: file some_file.txt does not exist
======================================================================
FAIL: test_002 (__main__.First_Test_Cases)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/tmp/test.py", line 15, in test_002
self.assertTrue(os.path.exists(gp), msg)
AssertionError: file some_file.txt does not exist
----------------------------------------------------------------------
Ran 2 tests in 0.000s
FAILED (failures=2)

How to get the exception thrown in unittest

I have my own exceptions and i want to test farther fields in the ex other then the message.
Reading this thread i tried the idea of using a context. I wrote this generic function
def test_runtime_error(test, exception_type, message, display_parameter, path, callable_obj, *args):
pdb.set_trace()
with test.assertRaises(exception_type) as cx:
callable_obj(*args)
ex = cx.exception
test.assertEqual(ex.message,message)
test.assertEqual(ex.display_parameter,display_parameter)
test.assertEqual(ex.path,path)
The path and display_parameter are my own specific fields. I'm not inventing the wheel here, i took most of it from the source.
I'm using it like that
class ExceptionsTest(unittest.TestCase):
def test_something(self):
data = {"name" : "A"}
obj = MyModel.objects.get(pk=1)
test_runtime_error(self,CustomException, 'message', 'A', [], obj.create, data)
The arguments are passed correctly into the callable_obj. the function raises the expected exception. but right after the execution of callable_obj the function breaks and the exception is not fetched. BTW, when i ran the same code in the test it self it worked fine.
Whats wrong here ?

The issue here appears to be this line:
pdb.set_trace()
If you leave it in, but don't have import pdb, the code below will fail with:
E
======================================================================
ERROR: testRaises (__main__.ExceptionTest)
----------------------------------------------------------------------
Traceback (most recent call last):
File "./except.py", line 22, in testRaises
self.verifyComplexException(MyException, 'asdf', RaiseException, 'asdf')
File "./except.py", line 14, in verifyComplexException
pdb.set_trace()
NameError: global name 'pdb' is not defined
----------------------------------------------------------------------
Ran 1 test in 0.000s
FAILED (errors=1)
which matches your description. If you do add the import pdb line, it will drop into the debugger, which is a completely different behavior that cannot be confused for the exit with E or exit with F status, so it can't be that.
Here's a complete example based on this idea which works as intended (licensed under Apache 2.0; see my repo):
import unittest
class MyException(Exception):
def __init__(self, message):
self.message = message
def RaiseException(message):
raise MyException(message)
class ExceptionTest(unittest.TestCase):
def verifyComplexException(self, exception_class, message, callable, *args):
with self.assertRaises(exception_class) as cm:
callable(*args)
exception = cm.exception
self.assertEqual(exception.message, message)
def testRaises(self):
self.verifyComplexException(MyException, 'asdf', RaiseException, 'asdf')
if __name__ == '__main__':
unittest.main()

How to fail a python unittest if the setUpClass throws exception

I am having little trouble using the python setUpClass.
For example consider the following case
class MyTest(unittest.case.TestCase):
#classmethod
def setUpClass(cls):
print "Test setup"
try:
1/0
except:
raise
#classmethod
def tearDownClass(cls):
print "Test teardown"
A couple of questions
Is the above code the right way to handle test setUpClass exceptions (by raising it so that the python unittest can take care of it), there are fail(), skip() methods, but those can only be used by test instances and not the test classes.
When there is a setUpClass exception, how can we ensure that tearDownClass runs (unittest doesn't run it, should we manualy call it).

You can call tearDownClass on an exception as Jeff points it out, but you may also implements the __del__(cls) method :
import unittest
class MyTest(unittest.case.TestCase):
#classmethod
def setUpClass(cls):
print "Test setup"
try:
1/0
except:
raise
#classmethod
def __del__(cls):
print "Test teardown"
def test_hello(cls):
print "Hello"
if __name__ == '__main__':
unittest.main()
Will have the following output :
Test setup
E
======================================================================
ERROR: setUpClass (__main__.MyTest)
----------------------------------------------------------------------
Traceback (most recent call last):
File "my_test.py", line 8, in setUpClass
1/0
ZeroDivisionError: integer division or modulo by zero
----------------------------------------------------------------------
Ran 0 tests in 0.000s
FAILED (errors=1)
Test teardown
Note : you should be aware that the __del__ method will be called at the end of the program execution, which is maybe not what you want if you have a more than one test class.
Hope it helps

The best option would be is to add handler for the except which calls tearDownClass and re-raise exception.
#classmethod
def setUpClass(cls):
try:
super(MyTest, cls).setUpClass()
# setup routine...
except Exception: # pylint: disable = W0703
super(MyTest, cls).tearDownClass()
raise

import contextlib
class MyTestCase(unitest.TestCase):
#classmethod
def setUpClass(cls):
with contextlib.ExitStack() as stack:
# ensure teardown is called if error occurs
stack.callback(cls.tearDownClass)
# Do the things here!
# remove callback at the end if no error found
stack.pop_all()

use tearDownModule. It should be called after setUpClass runs.

'SentinelObject' object has no attribute 'reset_mock'

I am not sure why the following code is not working. I am using the Mock framework. Anyone could explain it to me?
The error I get is this:
$ python test_mock.py
Calls the mock object method. not a real one. ... ERROR
======================================================================
ERROR: Calls the mock object method. not a real one.
----------------------------------------------------------------------
Traceback (most recent call last):
File "test_mock.py", line 37, in test_is_method_called
self.sut.do_something()
File "test_mock.py", line 21, in do_something
self.__obj.method()
File "build/bdist.linux-i686/egg/mock.py", line 365, in __getattr__
self._children[name] = self._get_child_mock(parent=self, name=name, wraps=wraps)
File "build/bdist.linux-i686/egg/mock.py", line 458, in _get_child_mock
return klass(**kw)
File "build/bdist.linux-i686/egg/mock.py", line 282, in __init__
self.reset_mock()
File "build/bdist.linux-i686/egg/mock.py", line 303, in reset_mock
self._return_value.reset_mock()
AttributeError: 'SentinelObject' object has no attribute 'reset_mock'
----------------------------------------------------------------------
Ran 1 test in 0.001s
FAILED (errors=1)
The code is:
import unittest
import mock
class Fubar ():
def __init__(self):
pass
def method (self):
print "I am a Stup!d Monkey!"
class Monkey ():
def __init__(self, obj):
self.__obj = obj
def do_something (self):
if not isinstance(self.__obj, Fubar):
raise RuntimeError
self.__obj.method()
class TestMoneky (unittest.TestCase):
def setUp(self):
self.mock_obj = mock.Mock(name="Mock object", spec=["method"])
self.sut = Monkey(self.mock_obj)
def tearDown(self):
pass
def test_is_method_called (self):
"""Calls the mock object method. not a real one."""
with mock.patch("__builtin__.isinstance") as mock_inst:
mock_inst.return_value = True
self.sut.do_something()
self.assertTrue(self.mock_obj.method.called)
def main ():
"""Simple runner."""
suite = unittest.TestSuite()
suite.addTest(unittest.makeSuite(TestMoneky))
unittest.TextTestRunner(verbosity=2).run(suite)
if __name__ == '__main__':
main()

The problems (sadly) is trivial. I am patching isinstance() to always return True. So, somewhere in the bowels of the module, something is asking whether my mock object is a Sentinel and (since I am overriding the return value), True is returned. Thus the wrong internal behaviour is exhibited.
The solution is therefore to not patch isinstance() but instead provide the mock with a spec that matches the class it is supposed to match:
def setUp(self):
self.mock_obj = mock.Mock(name="Mock object", spec=Fubar)
self.sut = Monkey(self.mock_obj)
def test_is_method_called (self):
"""Calls the mock object method. not a real one."""
self.sut.do_something()
self.assertTrue(self.mock_obj.method.called)
Can anyone see a way to do this without coupling the mock to Fubar???...

Using Nose to test txmongo dependent code

I want to use nose to test an application that I am writing using twisted and txmongo. I can't even get simple use cases like the following working:
from nose.twistedtools import reactor, deferred, threaded_reactor
import logging
from twisted.internet import defer
import txmongo
log = logging.getLogger("common.test.test_db")
conn = txmongo.lazyMongoConnectionPool('localhost', 27017, 4)
#deferred()
def test_mongo():
tdb = conn.test
#defer.inlineCallbacks
def cb(oid):
assert oid
obj = yield tdb.test.find({"_id":oid})
log.error("In callback")
assert obj
d = tdb.test.save({"s":1, "b":2})
d.addCallback(cb)
return d
However, this always return the following:
E
======================================================================
ERROR: common.test.test_db.test_mongo
----------------------------------------------------------------------
Traceback (most recent call last):
File "/Volumes/Users/jce/.pyenv/celery/lib/python2.6/site-packages/nose/case.py", line 186, in runTest
self.test(*self.arg)
File "/Volumes/Users/jce/.pyenv/celery/lib/python2.6/site-packages/nose/twistedtools.py", line 138, in errback
failure.raiseException()
File "/Volumes/Users/jce/.pyenv/celery/lib/python2.6/site-packages/twisted/python/failure.py", line 326, in raiseException
raise self.type, self.value, self.tb
RuntimeWarning: not connected
----------------------------------------------------------------------
Ran 1 test in 0.006s
FAILED (errors=1)
I tried manually adding a threaded_reactor() call, but it didn't help.
edit
I removed the "lazy" connections, and modified the code, and now it works... I'm still curious as to why the "lazy" didn't work. The working code is as follows:
dbconn = txmongo.MongoConnectionPool('localhost', 27017, 4)
#deferred()
def test_mongo():
#defer.inlineCallbacks
def cb(conn):
tdb = conn.test
oid = yield tdb.test.save({"s":1, "b":2})
assert oid
log.error(str(oid))
obj = yield tdb.test.find({"_id":oid})
assert obj
log.error(str(obj))
dbconn.addCallback(cb)
return dbconn

MongoConnectionPool will return a deferred, which is fired when the connection is established passing the connection handler as argument to the callback. You should conn = yield MongoConnectionPool().
lazyMongoConnectionPool will return the connection handler directly, without waiting for the connection to be established.
Lazy is usually used by web servers and other services that doesn't require immediate connection when your service starts. If you want to do so, don't use the lazy method.