base_test_class.py

from unittest import TestCase

class BaseTestClass(TestCase):
    """
    Base test class for the two components.
    """

    __test__ = False #important, makes sure tests are not run on base class

    component = None

    def shortDescription(self):
        """
        Get's the one liner description to be displayed.
        """

        doc = self._testMethodDoc
        doc = doc and doc.split("\n")[0].strip() or ""
        if "%(component)s" in doc:
            doc = doc % {'component':self.component.__name__}
        doc = "%s : %s" % (self.__class__.__name__, doc)

        return doc

    #implement setUp, tearDown, setUpClass and tearDownClass as per your needs

    def test_something(self):
        """ Test %(component)s constructor sets something. """

        comp = self.component()

        self.assertTrue(hasattr(comp, "something"))

    def test_initialized(self):
        """ Test that initialized is set. """

        comp = self.component()

        self.assertEquals(comp.initialized, True)

components.py

class AClass:
    """ The Amazing A Class. """

    def __init__(self):
        """ A class constructor. """

        self.something = False
        self.initialized = True


class BClass:
    """ The rebellious B Class. """

    def __init__(self):
        """ B class constructor. """

        self.something = True
        self.initialized = True

test_components.py

from base_test_class import BaseTestClass
from components import AClass, BClass

class TestA(BaseTestClass):
    """ Test the A class. """

    __test__ = True
    component = AClass


class TestB(BaseTestClass):
    """ Test the B class. """

    __test__ = True
    component = BClass

test_components_verbose.py

from components import AClass, BClass
from unittest import TestCase


class TestA(TestCase):
    """ Test the A class. """

    def test_something(self):
        """ Test A class constructor set something. """

        a = AClass()

        self.assertTrue(hasattr(a, "something"))

    def test_initialized(self):
        """ Test that initialized is set. """

        a = AClass()
        self.assertEquals(a.initialized, True)


class TestB(TestCase):
    """ Test the B class. """

    def test_something(self):
        """ Test B class constructor sets something. """

        b = BClass()

        self.assertTrue(hasattr(b, "something"))

    def test_initialized(self):
        """ Test that initialized is set. """

        b = BClass()
        self.assertEquals(b.initialized, True)

Thanks for this. Very helpful!