Subclassing unittest.TestCase?

Roy Smith roy at
Wed Nov 3 13:48:38 CET 2010

I'm using Python 2.6, with unittest2 imported as unittest.

I'm writing a test suite for a web application.  There is a subclass of 
TestCase for each basic page type.  One thing that's in common between 
all the pages is that every page must have a valid copyright notice.  It 
seems like the logical thing would be to put the common test(s) in a 
subclass unittest.TestCase and have all my real test cases derive from 

class CommonTestCase(unittest.TestCase):
   def test_copyright(self):
      self.assert_(find copyright notice in DOM tree)

class HomepageTestCase(CommonTestCase):
   def setUp(self):
      self.url = ""

   def test_whatever(self):

This works fine as far as HomepageTestCase running test_copyright() and 
test_whatever().  The problem is that CommonTestCase *also* runs 
test_copyright(), which fails because there's no setUp(), and thus no 
retrieved page for it to work on.

The hack that I came up with is:

class CommonTestCase(unittest.TestCase):
   def test_copyright(self):
      if self.__class__.__name__ == 'CommonTestCase':
      self.assert_(find copyright notice in DOM tree)

which works, but it's ugly.  It also counts 
CommonTestCase.test_copyright() as passing, which messes up the 
statistics.  Is there a cleaner way to define some common test methods 
which all of my test cases can inherit, without having them be run in 
the base class?

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