Python unittest with expensive setup

Question

My test file is basically:

class Test(unittest.TestCase):     def testOk():         pass  if __name__ == "__main__":     expensiveSetup()     try:         unittest.main()     finally:         cleanUp() 

However, I do wish to run my test through Netbeans testing tools, and to do that I need unittests that don't rely on an environment setup done in main. Looking at Caching result of setUp() using Python unittest - it recommends using Nose. However, I don't think Netbeans supports this. I didn't find any information indicating that it does. Additionally, I am the only one here actually writing tests, so I don't want to introduce additional dependencies for the other 2 developers unless they are needed.

How can I do the setup and cleanup once for all the tests in my TestSuite?

The expensive setup here is creating some files with dummy data, as well as setting up and tearing down a simple xml-rpc server. I also have 2 test classes, one testing locally and one testing all methods over xml-rpc.

Answer 1

If you use Python >= 2.7 (or unittest2 for Python >= 2.4 & <= 2.6), the best approach would be be to use

def setUpClass(cls):     # ... setUpClass = classmethod(setUpClass) 

to perform some initialization once for all tests belonging to the given class.

And to perform the cleanup, use:

@classmethod def tearDownClass(cls):     # ... 

See also the unittest standard library documentation on setUpClass and tearDownClass classmethods.

Answer 2

This is what I do:

class TestSearch(unittest.TestCase):     """General Search tests for...."""      matcher = None     counter      = 0     num_of_tests = None      def setUp(self): # pylint: disable-msg=C0103          """Only instantiate the matcher once"""         if self.matcher is None:             self.__class__.matcher = Matcher()             self.__class__.num_of_tests = len(filter(self.isTestMethod, dir(self)))         self.__class__.counter = self.counter + 1       def tearDown(self): # pylint: disable-msg=C0103         """And kill it when done"""         if self.counter == self.num_of_tests:             print 'KILL KILL KILL'             del self.__class__.matcher 

Sadly (because I do want my tests to be independent and deterministic), I do this a lot (because system testing that take less than 5 minutes are also important).